Re: Re: The effect of age on cycling Pedal Cadence

[Guest guest]

Marshall at 32 you are at still at your prime. You have no where to go but down

after this. I would be curious as to what resistance where you spinning against

when you performed these tests?

The changes over time would be due to improved neuromuscular coordination. I

guess the question really would be whether age would cause this to decrease over

time and by what % per decade. Your numbers are certainly impressive however I

doubt that you would be able to come near those numbers on the road or track or

under loading conditions.

It appears that the most efficient pedaling cadence is in the range of 85-95.

As the cadence increases above 100 more a greater % of energy is used just in

moving the legs and less goes directly to propelling the bike. Lower cadences

(higher gears) tend to engage the more of the type II fibers which are more

easily fatigued. Lower and higher cadences are fine for short periods of time

(climbing hills or short sprints) but are less efficient (energy wise) for long

races.

read the following article:

Fast Pedalling: Why fast pedaling makes cyclists more efficient.

RECENTLY we reported that cyclists are usually more efficient on both hills

and flat terrain when they pedal quickly (at about 80-85 rpm) rather than at

slower cadences. Now, a new study suggests that the greater efficiency may be

related to the rapid rate at which glycogen is depleted in fast-twitch muscle

fibres during slow, high-force pedaling.

To determine the actual effects of slow and fast pedaling on leg-muscle cells,

scientists at the University of Wisconsin and the University of Wyoming asked

eight experienced cyclists to cycle at an intensity of 85% V02max for 30 minutes

under two different conditions. In one case the cyclists pedaled their bikes at

50 revolutions per minute (rpm) while using a high gear. In the second case, the

athletes pedaled in a low gear at 100 rpm. The athletes were traveling at

identical speeds in the two instances, so their leg-muscle contractions were

quite forceful at 50 rpm and moderate - but more frequent - at 100 rpm.

As it turned out, the athletes' oxygen consumption rates were nearly identical

in the two cases, and heart and breathing rates, total rate of power production,

and blood lactate levels were also similar. However, athletes broke down the

carbohydrate in their muscles at a greater rate when the 50 rpm strategy was

used, while the 100 rpm cadence produced a greater reliance on fat. The greater

glycogen depletion at 50 rpm occurred only in fast-twitch muscle cells.

Slow-twitch muscle cells lost comparable amounts of their glycogen at 50 and 100

rpm, but fast-twitch cells lost almost 50 per cent of their glycogen at 50 rpm

and only 33 per cent at 100 rpm, even though the exercise bouts lasted for 30

minutes in each case.

This rapid loss of carbohydrate in the fast-twitch cells during slow,

high-force pedaling probably explains why slow pedaling is less efficient than

faster cadences of 80-85 rpm. Basically, as the fast fibres quickly deplete

their glycogen during slow, high-strength pedaling, their contractions become

less forceful, so more muscle cells must be activated to maintain a particular

speed. This activation of a larger number of muscle cells then leads to higher

oxygen consumption rates and reduced economy.

This scenario, in which slow pedaling pulls the glycogen out of fast-twitch

muscle cells, may sound paradoxical but it isn't; after all, slow pedaling rates

are linked with high gears and elevated muscle forces, while fast cadences are

associated with low gears and easy muscle contractions. Since fast-twitch fibres

are more powerful than slow-twitch cells, the fast twitchers swing into action

at slow cadences, when high muscular forces are needed to move the bicycle along

rapidly. On the other hand, 'fast' pedaling rates of 80-100 rpm are not too hot

for the slow-twitch cells to handle. Slow-twitch cells can contract 80-100 times

per minute and can easily cope with the forces required to pedal in low gear.

Another possible paradox in the Wisconsin Wyoming research was that fast

pedaling led to greater fat oxidation even though maximal fat burning is usually

linked with slow-paced efforts. Basically, the higher fat degradation at 100 rpm

occurred because the slow-twitch cells handled the fast-paced, low-force

contractions. Slow-twitch fibres are much better fat-burners than their

fast-twitch neighbours.

Fortunately, there's a bottom line to all this: during training and

competition, cyclists should attempt to use fast pedaling rates of 80-85 rpm,

both on the flat and on inclines. Compared to slower cadences, the higher

pedaling speeds are more economical and burn more fat during exercise.

Ultimately, the high pedaling rates also preserve greater amounts of glycogen in

fast-twitch muscle fibres, leading to more explosive 'kicks' to the finish line

in closing moments of races. \(European Journal of Applied Physiology, 1992)

+++++++++++++++++++++++++++++++++++++++++++++++++++

Ralph Giarnella MD

Southington Ct USA

________________________________

From: endlesscycles <endlesscycles@...>

Supertraining

Sent: Thu, November 26, 2009 3:59:59 PM

Subject: Re: The effect of age on cycling Pedal Cadence

While I am still relatively young at 32, I have seen no decrease in my ability

to spin a high cadence. I've had cadence meters infrequently since my early

teen's, and have seen only positive change in my maximum cadence (220rpm at

13yrs, 240 at 22yrs, 250rpm two days ago) despite only going so high simply to

test myself those three instances.

-Marshall Hance

Asheville, NC

>

> Many Masters riders contend that lower cadence and therefore higher gears is

necessary for them where younger riders can cope with higher cadence and

therefore lower gears.

>

> As a 48 year old masters track rider myself, I know that I can almost be

guaranteed of being dropped in a track race (short or long)if I ride a

comparitively low gear (say 88 gear inches) and will be far more comfortable

(and competitive) with a 92 to 94 gear inches where many of the younger riders

(under 30 years of age) are much more comfortable with lower gears and higher

cadence.

>

> I wonder about the reasons including:

> 1. Is this due to my never having learnt to ride efficiently at a high cadence

when I was younger (I only came to competitive cycling in my late 40's

> 2. Is there a physiological basis limiting high cadence in older riders e.g.

reduction in the number or efficiency of fast twitch fibres with age

> 3. It's generally accepted that cadence and heartrate are closely related and

that MHR reduces with age - So will the reduction in MHR with age be a major

factor in limiting cadence?

>

> Phil Bushell

> Melbourne Australia

>

[Guest guest]

Marshall at 32 you are at still at your prime. You have no where to go but down

after this. I would be curious as to what resistance where you spinning against

when you performed these tests?

The changes over time would be due to improved neuromuscular coordination. I

guess the question really would be whether age would cause this to decrease over

time and by what % per decade. Your numbers are certainly impressive however I

doubt that you would be able to come near those numbers on the road or track or

under loading conditions.

It appears that the most efficient pedaling cadence is in the range of 85-95.

As the cadence increases above 100 more a greater % of energy is used just in

moving the legs and less goes directly to propelling the bike. Lower cadences

(higher gears) tend to engage the more of the type II fibers which are more

easily fatigued. Lower and higher cadences are fine for short periods of time

(climbing hills or short sprints) but are less efficient (energy wise) for long

races.

read the following article:

Fast Pedalling: Why fast pedaling makes cyclists more efficient.

RECENTLY we reported that cyclists are usually more efficient on both hills

and flat terrain when they pedal quickly (at about 80-85 rpm) rather than at

slower cadences. Now, a new study suggests that the greater efficiency may be

related to the rapid rate at which glycogen is depleted in fast-twitch muscle

fibres during slow, high-force pedaling.

To determine the actual effects of slow and fast pedaling on leg-muscle cells,

scientists at the University of Wisconsin and the University of Wyoming asked

eight experienced cyclists to cycle at an intensity of 85% V02max for 30 minutes

under two different conditions. In one case the cyclists pedaled their bikes at

50 revolutions per minute (rpm) while using a high gear. In the second case, the

athletes pedaled in a low gear at 100 rpm. The athletes were traveling at

identical speeds in the two instances, so their leg-muscle contractions were

quite forceful at 50 rpm and moderate - but more frequent - at 100 rpm.

As it turned out, the athletes' oxygen consumption rates were nearly identical

in the two cases, and heart and breathing rates, total rate of power production,

and blood lactate levels were also similar. However, athletes broke down the

carbohydrate in their muscles at a greater rate when the 50 rpm strategy was

used, while the 100 rpm cadence produced a greater reliance on fat. The greater

glycogen depletion at 50 rpm occurred only in fast-twitch muscle cells.

Slow-twitch muscle cells lost comparable amounts of their glycogen at 50 and 100

rpm, but fast-twitch cells lost almost 50 per cent of their glycogen at 50 rpm

and only 33 per cent at 100 rpm, even though the exercise bouts lasted for 30

minutes in each case.

This rapid loss of carbohydrate in the fast-twitch cells during slow,

high-force pedaling probably explains why slow pedaling is less efficient than

faster cadences of 80-85 rpm. Basically, as the fast fibres quickly deplete

their glycogen during slow, high-strength pedaling, their contractions become

less forceful, so more muscle cells must be activated to maintain a particular

speed. This activation of a larger number of muscle cells then leads to higher

oxygen consumption rates and reduced economy.

This scenario, in which slow pedaling pulls the glycogen out of fast-twitch

muscle cells, may sound paradoxical but it isn't; after all, slow pedaling rates

are linked with high gears and elevated muscle forces, while fast cadences are

associated with low gears and easy muscle contractions. Since fast-twitch fibres

are more powerful than slow-twitch cells, the fast twitchers swing into action

at slow cadences, when high muscular forces are needed to move the bicycle along

rapidly. On the other hand, 'fast' pedaling rates of 80-100 rpm are not too hot

for the slow-twitch cells to handle. Slow-twitch cells can contract 80-100 times

per minute and can easily cope with the forces required to pedal in low gear.

Another possible paradox in the Wisconsin Wyoming research was that fast

pedaling led to greater fat oxidation even though maximal fat burning is usually

linked with slow-paced efforts. Basically, the higher fat degradation at 100 rpm

occurred because the slow-twitch cells handled the fast-paced, low-force

contractions. Slow-twitch fibres are much better fat-burners than their

fast-twitch neighbours.

Fortunately, there's a bottom line to all this: during training and

competition, cyclists should attempt to use fast pedaling rates of 80-85 rpm,

both on the flat and on inclines. Compared to slower cadences, the higher

pedaling speeds are more economical and burn more fat during exercise.

Ultimately, the high pedaling rates also preserve greater amounts of glycogen in

fast-twitch muscle fibres, leading to more explosive 'kicks' to the finish line

in closing moments of races. \(European Journal of Applied Physiology, 1992)

+++++++++++++++++++++++++++++++++++++++++++++++++++

Ralph Giarnella MD

Southington Ct USA

________________________________

From: endlesscycles <endlesscycles@...>

Supertraining

Sent: Thu, November 26, 2009 3:59:59 PM

Subject: Re: The effect of age on cycling Pedal Cadence

While I am still relatively young at 32, I have seen no decrease in my ability

to spin a high cadence. I've had cadence meters infrequently since my early

teen's, and have seen only positive change in my maximum cadence (220rpm at

13yrs, 240 at 22yrs, 250rpm two days ago) despite only going so high simply to

test myself those three instances.

-Marshall Hance

Asheville, NC

>

> Many Masters riders contend that lower cadence and therefore higher gears is

necessary for them where younger riders can cope with higher cadence and

therefore lower gears.

>

> As a 48 year old masters track rider myself, I know that I can almost be

guaranteed of being dropped in a track race (short or long)if I ride a

comparitively low gear (say 88 gear inches) and will be far more comfortable

(and competitive) with a 92 to 94 gear inches where many of the younger riders

(under 30 years of age) are much more comfortable with lower gears and higher

cadence.

>

> I wonder about the reasons including:

> 1. Is this due to my never having learnt to ride efficiently at a high cadence

when I was younger (I only came to competitive cycling in my late 40's

> 2. Is there a physiological basis limiting high cadence in older riders e.g.

reduction in the number or efficiency of fast twitch fibres with age

> 3. It's generally accepted that cadence and heartrate are closely related and

that MHR reduces with age - So will the reduction in MHR with age be a major

factor in limiting cadence?

>

> Phil Bushell

> Melbourne Australia

>

[Guest guest]

On Nov 27, 2009, at 7:32:25 AM, " Ralph Giarnella " <ragiarn@...> attached a

study that reported:

Basically, as the fast fibres quickly deplete their glycogen during slow,

high-strength pedaling, their contractions become less forceful, so more muscle

cells must be activated to maintain a particular speed. This activation of a

larger number of muscle cells then leads to higher oxygen consumption rates and

reduced economy.

But in the paragraph preceding:

>>As it turned out, the athletes' oxygen consumption rates were nearly identical

in the two cases, and heart and breathing rates, total rate of power production,

and blood lactate levels were also similar.<<

Sounds to me like the " probable explanation " is actually an

 hypothesis (unproven) that is unwarranted and unsupported by the observations.

 What am I missing here?

Otherwise, the report of the study itself seems reasonable and for me, at least,

enlightening.  Thanks for submitting it.

Boardman

Chicago, USA 

[Guest guest]

On Nov 27, 2009, at 7:32:25 AM, " Ralph Giarnella " <ragiarn@...> attached a

study that reported:

Basically, as the fast fibres quickly deplete their glycogen during slow,

high-strength pedaling, their contractions become less forceful, so more muscle

cells must be activated to maintain a particular speed. This activation of a

larger number of muscle cells then leads to higher oxygen consumption rates and

reduced economy.

But in the paragraph preceding:

>>As it turned out, the athletes' oxygen consumption rates were nearly identical

in the two cases, and heart and breathing rates, total rate of power production,

and blood lactate levels were also similar.<<

Sounds to me like the " probable explanation " is actually an

 hypothesis (unproven) that is unwarranted and unsupported by the observations.

 What am I missing here?

Otherwise, the report of the study itself seems reasonable and for me, at least,

enlightening.  Thanks for submitting it.

Boardman

Chicago, USA 

[Guest guest]

I agree with that the article is somewhat contradictory. In a nutshell,

according to the logic of the article the faster pedaling the better. So

following this logic to an extreme 200 rpm should even be better than 100

rpm. I think that Ralph puts it right in his statement: " As the cadence

increases above 100 more a greater % of energy is used just in moving the

legs and less goes directly to propelling the bike " . So there is a trade off

in there, that the article completely misses.

So while I do not dispute the results of the U.of Wisconsin/Wyoming study, I

think Hunter who wrote the article cited by Ralph,

http://www.active.com/cycling/Articles/Why_fast_pedaling_makes_cyclists_more_eff\

icient.htm,

didn't fully understand it. I also think that the best rpm depends very much

on the Fast Twitch-Slow Twitch mix of the individual athlete.

Finally it doesn't make sense to discuss rpm without crank length. What

should be discussed is rpm x crank length, because if I obtain one result at

100 rpm x 185 mm crank, I should repeat exactly the same performance at 97

rpm x 190 mm crank: i.e. same wattage, speed, VO2 and all other metabolic

indicators, granted with a different gear.

Giovanni Ciriani - West Hartford, CT - USA

On Fri, Nov 27, 2009 at 2:21 PM, paula206 <A206@...> wrote:

>

>

> On Nov 27, 2009, at 7:32:25 AM, " Ralph Giarnella "

<ragiarn@...<ragiarn%40>>

> attached a study that reported:

>

>

> Basically, as the fast fibres quickly deplete their glycogen during slow,

> high-strength pedaling, their contractions become less forceful, so more

> muscle cells must be activated to maintain a particular speed. This

> activation of a larger number of muscle cells then leads to higher oxygen

> consumption rates and reduced economy.

> But in the paragraph preceding:

>

>

> >>As it turned out, the athletes' oxygen consumption rates were nearly

> identical in the two cases, and heart and breathing rates, total rate of

> power production, and blood lactate levels were also similar.<<

>

> Sounds to me like the " probable explanation " is actually an

> hypothesis (unproven) that is unwarranted and unsupported by the

> observations. What am I missing here?

>

> Otherwise, the report of the study itself seems reasonable and for me, at

> least, enlightening. Thanks for submitting it.

>

> Boardman

>

> Chicago, USA

>

>

>

[Guest guest]

I agree with that the article is somewhat contradictory. In a nutshell,

according to the logic of the article the faster pedaling the better. So

following this logic to an extreme 200 rpm should even be better than 100

rpm. I think that Ralph puts it right in his statement: " As the cadence

increases above 100 more a greater % of energy is used just in moving the

legs and less goes directly to propelling the bike " . So there is a trade off

in there, that the article completely misses.

So while I do not dispute the results of the U.of Wisconsin/Wyoming study, I

think Hunter who wrote the article cited by Ralph,

http://www.active.com/cycling/Articles/Why_fast_pedaling_makes_cyclists_more_eff\

icient.htm,

didn't fully understand it. I also think that the best rpm depends very much

on the Fast Twitch-Slow Twitch mix of the individual athlete.

Finally it doesn't make sense to discuss rpm without crank length. What

should be discussed is rpm x crank length, because if I obtain one result at

100 rpm x 185 mm crank, I should repeat exactly the same performance at 97

rpm x 190 mm crank: i.e. same wattage, speed, VO2 and all other metabolic

indicators, granted with a different gear.

Giovanni Ciriani - West Hartford, CT - USA

On Fri, Nov 27, 2009 at 2:21 PM, paula206 <A206@...> wrote:

>

>

> On Nov 27, 2009, at 7:32:25 AM, " Ralph Giarnella "

<ragiarn@...<ragiarn%40>>

> attached a study that reported:

>

>

> Basically, as the fast fibres quickly deplete their glycogen during slow,

> high-strength pedaling, their contractions become less forceful, so more

> muscle cells must be activated to maintain a particular speed. This

> activation of a larger number of muscle cells then leads to higher oxygen

> consumption rates and reduced economy.

> But in the paragraph preceding:

>

>

> >>As it turned out, the athletes' oxygen consumption rates were nearly

> identical in the two cases, and heart and breathing rates, total rate of

> power production, and blood lactate levels were also similar.<<

>

> Sounds to me like the " probable explanation " is actually an

> hypothesis (unproven) that is unwarranted and unsupported by the

> observations. What am I missing here?

>

> Otherwise, the report of the study itself seems reasonable and for me, at

> least, enlightening. Thanks for submitting it.

>

> Boardman

>

> Chicago, USA

>

>

>

[Guest guest]

Finally it doesn't make sense to discuss rpm without crank length. What

should be discussed is rpm x crank length, because if I obtain one result at

100 rpm x 185 mm crank, I should repeat exactly the same performance at 97

rpm x 190 mm crank: i.e. same wattage, speed, VO2 and all other metabolic

indicators, granted with a different gear.

Giovanni Ciriani - West Hartford, CT - US

******************

The standard crank length used by most cyclists is 175- Shorter than riders may

use cranks as short as 172 or 170- they have to be special ordered and taller

than average riders (read in both instances short thigh length and longer thigh

length) will use longer crank arms of 180-185- again they need to b special

ordered. Some will use 180s for flat time trials where acceleration is not an

issue and once the Time trialists has gotten into a rhtym there is no need to

change cadence.

Despite any possible mechanical advantages a shorter or longer crank arm might

theoretically have experience over decades has shown this to be the most

efficint crank arm length for the average thigh length.

Remember racing is not a steady state but rapid fluctuations in speed and the

ability to accelerate to higher cadence makes the difference between making a

break in a race or getting dropped by the peloton. The only exception to this is

a flat time trial where a racer can use the lower gears to get up to speed and

then maintain a high steady state speed. Pretty much like starting out when the

light turns green and you need to accelerate contantly changing gears until

finally get to cruising speed shift into high gear. That is for those of us who

remember how to use a stick shift.

Unless stated other wise it is safe to assume that the cyclists in the study all

had standard 175 mm crank arms.

As I stated in my previous post cyclists have experimented over the past 100

years and the choice of 175 mm crank arms has come about through trial and error

and not based on an engineer or scientists formulation. It is up to the

scientist or engineer to figure out why a particular crank arm length and

cadence turns out to be the most efficient way of racing a bicycle. Just

because a study has not been studied to prove does not mean it is not efficient.

Rarely does a world class athlete achieve that goal using inefficient training

methods or equipment.

Ralph Giarnella MD

Southington Ct USA

________________________________

From: Giovanni Ciriani <Giovanni.Ciriani@...>

Supertraining

Sent: Fri, November 27, 2009 5:56:15 PM

Subject: Re: Re: The effect of age on cycling Pedal Cadence

I agree with that the article is somewhat contradictory. In a nutshell,

according to the logic of the article the faster pedaling the better. So

following this logic to an extreme 200 rpm should even be better than 100

rpm. I think that Ralph puts it right in his statement: " As the cadence

increases above 100 more a greater % of energy is used just in moving the

legs and less goes directly to propelling the bike " . So there is a trade off

in there, that the article completely misses.

So while I do not dispute the results of the U.of Wisconsin/Wyoming study, I

think Hunter who wrote the article cited by Ralph,

http://www.active. com/cycling/ Articles/ Why_fast_ pedaling_ makes_cyclists_

more_efficient. htm,

didn't fully understand it. I also think that the best rpm depends very much

on the Fast Twitch-Slow Twitch mix of the individual athlete.

Finally it doesn't make sense to discuss rpm without crank length. What

should be discussed is rpm x crank length, because if I obtain one result at

100 rpm x 185 mm crank, I should repeat exactly the same performance at 97

rpm x 190 mm crank: i.e. same wattage, speed, VO2 and all other metabolic

indicators, granted with a different gear.

Giovanni Ciriani - West Hartford, CT - USA

On Fri, Nov 27, 2009 at 2:21 PM, paula206 <A206aol (DOT) com> wrote:

>

>

> On Nov 27, 2009, at 7:32:25 AM, " Ralph Giarnella " <ragiarn (DOT)

com<ragiarn%40. com>>

> attached a study that reported:

>

>

> Basically, as the fast fibres quickly deplete their glycogen during slow,

> high-strength pedaling, their contractions become less forceful, so more

> muscle cells must be activated to maintain a particular speed. This

> activation of a larger number of muscle cells then leads to higher oxygen

> consumption rates and reduced economy.

> But in the paragraph preceding:

>

>

> >>As it turned out, the athletes' oxygen consumption rates were nearly

> identical in the two cases, and heart and breathing rates, total rate of

> power production, and blood lactate levels were also similar.<<

>

> Sounds to me like the " probable explanation " is actually an

> hypothesis (unproven) that is unwarranted and unsupported by the

> observations. What am I missing here?

>

> Otherwise, the report of the study itself seems reasonable and for me, at

> least, enlightening. Thanks for submitting it.

>

> Boardman

>

> Chicago, USA

>

>

>

[Guest guest]

Finally it doesn't make sense to discuss rpm without crank length. What

should be discussed is rpm x crank length, because if I obtain one result at

100 rpm x 185 mm crank, I should repeat exactly the same performance at 97

rpm x 190 mm crank: i.e. same wattage, speed, VO2 and all other metabolic

indicators, granted with a different gear.

Giovanni Ciriani - West Hartford, CT - US

******************

The standard crank length used by most cyclists is 175- Shorter than riders may

use cranks as short as 172 or 170- they have to be special ordered and taller

than average riders (read in both instances short thigh length and longer thigh

length) will use longer crank arms of 180-185- again they need to b special

ordered. Some will use 180s for flat time trials where acceleration is not an

issue and once the Time trialists has gotten into a rhtym there is no need to

change cadence.

Despite any possible mechanical advantages a shorter or longer crank arm might

theoretically have experience over decades has shown this to be the most

efficint crank arm length for the average thigh length.

Remember racing is not a steady state but rapid fluctuations in speed and the

ability to accelerate to higher cadence makes the difference between making a

break in a race or getting dropped by the peloton. The only exception to this is

a flat time trial where a racer can use the lower gears to get up to speed and

then maintain a high steady state speed. Pretty much like starting out when the

light turns green and you need to accelerate contantly changing gears until

finally get to cruising speed shift into high gear. That is for those of us who

remember how to use a stick shift.

Unless stated other wise it is safe to assume that the cyclists in the study all

had standard 175 mm crank arms.

As I stated in my previous post cyclists have experimented over the past 100

years and the choice of 175 mm crank arms has come about through trial and error

and not based on an engineer or scientists formulation. It is up to the

scientist or engineer to figure out why a particular crank arm length and

cadence turns out to be the most efficient way of racing a bicycle. Just

because a study has not been studied to prove does not mean it is not efficient.

Rarely does a world class athlete achieve that goal using inefficient training

methods or equipment.

Ralph Giarnella MD

Southington Ct USA

________________________________

From: Giovanni Ciriani <Giovanni.Ciriani@...>

Supertraining

Sent: Fri, November 27, 2009 5:56:15 PM

Subject: Re: Re: The effect of age on cycling Pedal Cadence

I agree with that the article is somewhat contradictory. In a nutshell,

according to the logic of the article the faster pedaling the better. So

following this logic to an extreme 200 rpm should even be better than 100

rpm. I think that Ralph puts it right in his statement: " As the cadence

increases above 100 more a greater % of energy is used just in moving the

legs and less goes directly to propelling the bike " . So there is a trade off

in there, that the article completely misses.

So while I do not dispute the results of the U.of Wisconsin/Wyoming study, I

think Hunter who wrote the article cited by Ralph,

http://www.active. com/cycling/ Articles/ Why_fast_ pedaling_ makes_cyclists_

more_efficient. htm,

didn't fully understand it. I also think that the best rpm depends very much

on the Fast Twitch-Slow Twitch mix of the individual athlete.

Finally it doesn't make sense to discuss rpm without crank length. What

should be discussed is rpm x crank length, because if I obtain one result at

100 rpm x 185 mm crank, I should repeat exactly the same performance at 97

rpm x 190 mm crank: i.e. same wattage, speed, VO2 and all other metabolic

indicators, granted with a different gear.

Giovanni Ciriani - West Hartford, CT - USA

On Fri, Nov 27, 2009 at 2:21 PM, paula206 <A206aol (DOT) com> wrote:

>

>

> On Nov 27, 2009, at 7:32:25 AM, " Ralph Giarnella " <ragiarn (DOT)

com<ragiarn%40. com>>

> attached a study that reported:

>

>

> Basically, as the fast fibres quickly deplete their glycogen during slow,

> high-strength pedaling, their contractions become less forceful, so more

> muscle cells must be activated to maintain a particular speed. This

> activation of a larger number of muscle cells then leads to higher oxygen

> consumption rates and reduced economy.

> But in the paragraph preceding:

>

>

> >>As it turned out, the athletes' oxygen consumption rates were nearly

> identical in the two cases, and heart and breathing rates, total rate of

> power production, and blood lactate levels were also similar.<<

>

> Sounds to me like the " probable explanation " is actually an

> hypothesis (unproven) that is unwarranted and unsupported by the

> observations. What am I missing here?

>

> Otherwise, the report of the study itself seems reasonable and for me, at

> least, enlightening. Thanks for submitting it.

>

> Boardman

>

> Chicago, USA

>

>

>

[Guest guest]

Boardman wrote:

Basically, as the fast fibres quickly deplete their glycogen during

slow, high-strength pedaling, their contractions become less forceful,

so more muscle cells must be activated to maintain a particular speed.

This activation of a larger number of muscle cells then leads to higher

oxygen consumption rates and reduced economy.

But in the paragraph preceding:

>>As it turned out, the athletes' oxygen consumption rates were

nearly identical in the two cases, and heart and breathing rates, total

rate of power production, and blood lactate levels were also

similar.<<

Sounds to me like the " probable explanation " is actually an hypothesis

(unproven ) that is unwarranted and unsupported by the observations.

What am I missing here?

Otherwise, the report of the study itself seems reasonable and for me, at least,

enlightening. Thanks for submitting it.

Boardman

Chicago, USA

_______________________________

you make a good point. Unfortunately the author does not give the

title and reference for the original article so it is difficult to

track it down for specifics.

In reading his article it is important to distinguish where he stops

reporting the results of the study and begins to explain his take on

the study. I have re read the article and have attempted to

differentiate the point where he stops reporting the results and puts

in his interpretation. See if you agree.

**********************************************

Fast Pedalling: Why fast pedaling makes cyclists more efficient.

RECENTLY we reported that cyclists are usually more efficient on

both hills and flat terrain when they pedal quickly (at about 80-85

rpm) rather than at slower cadences. Now, a new study suggests that the

greater efficiency may be related to the rapid rate at which glycogen

is depleted in fast-twitch muscle fibres during slow, high-force

pedaling.

( In my opinion this is were reporting the finding of the study

begins:RGMD)

To determine the actual effects of slow and fast pedaling on

leg-muscle cells, scientists at the University of Wisconsin and the

University of Wyoming asked eight experienced cyclists to cycle at an

intensity of 85% V02max for 30 minutes under two different conditions.

In one case the cyclists pedaled their bikes at 50 revolutions per

minute (rpm) while using a high gear. In the second case, the athletes

pedaled in a low gear at 100 rpm.

The athletes were traveling at Identical speeds in the two instances,

so their leg-muscle contractions were quite forceful at 50 rpm and

moderate - but more frequent - at 100 rpm.

As it turned out, the athletes' oxygen consumption rates were nearly

identical in the two cases, and heart and breathing rates, total rate

of power production, and blood lactate levels were also similar.

(this does not seem to be the authors opinion but he is reporting the

findings of the study. The fact that all the stats are similar is

important in my opinion because is shows that in both instances the

same of work was done and the same amount of energy was utilize RGMD)

However, athletes broke down the carbohydrate in their muscles at a

greater rate when the 50 rpm strategy was used, while the 100 rpm

cadence produced a greater reliance on fat. The greater glycogen

depletion at 50 rpm occurred only in fast-twitch muscle cells.

(This statement, which I believe is still reporting the original

study's finding, shows that more glycogen was used at 50 rpm than at

100 rpm. This is important for the endurance athlete because glycogen

is in limited supply and when it runs out that is when the athlete hits

the proverbial " wall " RGMD )

Slow-twitch muscle cells lost comparable amounts of their glycogen at

50 and 100 rpm, but fast-twitch cells lost almost 50 per cent of their

glycogen at 50 rpm and only 33 per cent at 100 rpm, even though the

exercise bouts lasted for 30 minutes in each case.

(This statement, which I believe is still reporting the study's

finding, is important because f the fast twitch cells lost 50% of their

glycogen after 30 min it means that the muscles will be depleted in 1

hr whereas if only 33% of glycogen is depleted the athlete will be able

to continue for 90 minutes before hitting the wall.)

In my opinion this is where reporting on the study ends and his

interpretation begins. The study would be useless unless the authors

also evaluated the source of energy in both arm of the study and how

much of each source (glycogen vs fat) was utilized.

In my opinion the study shows that while both arms of the study

produced the same amount of work what differentiates the groups is the

energy source utilized at each rpm.

(In my opinion this is where the author of the article gives his interpretations

of the study.RGMD)

This rapid loss of carbohydrate in the fast-twitch cells during slow,

high-force pedaling probably explains why slow pedaling is less

efficient than faster cadences of 80-85 rpm. Basically, as the fast

fibres quickly deplete their glycogen during slow, high-strength

pedaling, their contractions become less forceful, so more muscle cells

must be activated to maintain a particular speed. This activation of a

larger number of muscle cells then leads to higher oxygen consumption

rates and reduced economy.

This scenario, in which slow pedaling pulls the glycogen out of

fast-twitch muscle cells, may sound paradoxical but it isn't; after

all, slow pedaling rates are linked with high gears and elevated muscle

forces, while fast cadences are associated with low gears and easy

muscle contractions. Since fast-twitch fibres are more powerful than

slow-twitch cells, the fast twitchers swing into action at slow

cadences, when high muscular forces are needed to move the bicycle

along rapidly. On the other hand, 'fast' pedaling rates of 80-100 rpm

are not too hot for the slow-twitch cells to handle. Slow-twitch cells

can contract 80-100 times per minute and can easily cope with the

forces required to pedal in low gear.

Another possible paradox in the Wisconsin Wyoming research was that

fast pedaling led to greater fat oxidation even though maximal fat

burning is usually linked with slow-paced efforts. Basically, the

higher fat degradation at 100 rpm occurred because the slow-twitch

cells handled the fast-paced, low-force contractions. Slow-twitch

fibres are much better fat-burners than their fast-twitch neighbours.

Fortunately, there's a bottom line to all this: during training and

competition, cyclists should attempt to use fast pedaling rates of

80-85 rpm, both on the flat and on inclines. Compared to slower

cadences, the higher pedaling speeds are more economical and burn more

fat during exercise. Ultimately, the high pedaling rates also preserve

greater amounts of glycogen in fast-twitch muscle fibres, leading to

more explosive 'kicks' to the finish line in closing moments of races.

\(European Journal of Applied Physiology, 1992)

******************************

My take on the study:

Cyclists over time have learned that the most efficient cadence is in

the range of 85-95 rpms. They learned this through trial and error

without the aid of scientists to tell them how fast they should pedal.

Studies such as the Wisconsin Wyoming are just trying to understand why

this cadence range is more efficient.

When I first decided to take cycling seriously and enter the

competitive arena and train for races I joined a local club with a

group of seasoned Cat II racers. As a beginner I naturally gravitated

to using big gears. It is not easy to pedal at a high cadence. I was

surprised when one of the Cat II racers took me aside and explained

that I needed to learn to use smaller gears and higher cadence. He

told me my muscles would not tire out so quickly if used the higher

cadences. He had not read this in a book or consulted scientists.

" You can't teach an old dog new tricks " . Well at age 45 I had to learn

a few new tricks. It took a long time but I learned how to pedal

fast..

[Guest guest]

Boardman wrote:

Basically, as the fast fibres quickly deplete their glycogen during

slow, high-strength pedaling, their contractions become less forceful,

so more muscle cells must be activated to maintain a particular speed.

This activation of a larger number of muscle cells then leads to higher

oxygen consumption rates and reduced economy.

But in the paragraph preceding:

>>As it turned out, the athletes' oxygen consumption rates were

nearly identical in the two cases, and heart and breathing rates, total

rate of power production, and blood lactate levels were also

similar.<<

Sounds to me like the " probable explanation " is actually an hypothesis

(unproven ) that is unwarranted and unsupported by the observations.

What am I missing here?

Otherwise, the report of the study itself seems reasonable and for me, at least,

enlightening. Thanks for submitting it.

Boardman

Chicago, USA

_______________________________

you make a good point. Unfortunately the author does not give the

title and reference for the original article so it is difficult to

track it down for specifics.

In reading his article it is important to distinguish where he stops

reporting the results of the study and begins to explain his take on

the study. I have re read the article and have attempted to

differentiate the point where he stops reporting the results and puts

in his interpretation. See if you agree.

**********************************************

Fast Pedalling: Why fast pedaling makes cyclists more efficient.

RECENTLY we reported that cyclists are usually more efficient on

both hills and flat terrain when they pedal quickly (at about 80-85

rpm) rather than at slower cadences. Now, a new study suggests that the

greater efficiency may be related to the rapid rate at which glycogen

is depleted in fast-twitch muscle fibres during slow, high-force

pedaling.

( In my opinion this is were reporting the finding of the study

begins:RGMD)

To determine the actual effects of slow and fast pedaling on

leg-muscle cells, scientists at the University of Wisconsin and the

University of Wyoming asked eight experienced cyclists to cycle at an

intensity of 85% V02max for 30 minutes under two different conditions.

In one case the cyclists pedaled their bikes at 50 revolutions per

minute (rpm) while using a high gear. In the second case, the athletes

pedaled in a low gear at 100 rpm.

The athletes were traveling at Identical speeds in the two instances,

so their leg-muscle contractions were quite forceful at 50 rpm and

moderate - but more frequent - at 100 rpm.

As it turned out, the athletes' oxygen consumption rates were nearly

identical in the two cases, and heart and breathing rates, total rate

of power production, and blood lactate levels were also similar.

(this does not seem to be the authors opinion but he is reporting the

findings of the study. The fact that all the stats are similar is

important in my opinion because is shows that in both instances the

same of work was done and the same amount of energy was utilize RGMD)

However, athletes broke down the carbohydrate in their muscles at a

greater rate when the 50 rpm strategy was used, while the 100 rpm

cadence produced a greater reliance on fat. The greater glycogen

depletion at 50 rpm occurred only in fast-twitch muscle cells.

(This statement, which I believe is still reporting the original

study's finding, shows that more glycogen was used at 50 rpm than at

100 rpm. This is important for the endurance athlete because glycogen

is in limited supply and when it runs out that is when the athlete hits

the proverbial " wall " RGMD )

Slow-twitch muscle cells lost comparable amounts of their glycogen at

50 and 100 rpm, but fast-twitch cells lost almost 50 per cent of their

glycogen at 50 rpm and only 33 per cent at 100 rpm, even though the

exercise bouts lasted for 30 minutes in each case.

(This statement, which I believe is still reporting the study's

finding, is important because f the fast twitch cells lost 50% of their

glycogen after 30 min it means that the muscles will be depleted in 1

hr whereas if only 33% of glycogen is depleted the athlete will be able

to continue for 90 minutes before hitting the wall.)

In my opinion this is where reporting on the study ends and his

interpretation begins. The study would be useless unless the authors

also evaluated the source of energy in both arm of the study and how

much of each source (glycogen vs fat) was utilized.

In my opinion the study shows that while both arms of the study

produced the same amount of work what differentiates the groups is the

energy source utilized at each rpm.

(In my opinion this is where the author of the article gives his interpretations

of the study.RGMD)

This rapid loss of carbohydrate in the fast-twitch cells during slow,

high-force pedaling probably explains why slow pedaling is less

efficient than faster cadences of 80-85 rpm. Basically, as the fast

fibres quickly deplete their glycogen during slow, high-strength

pedaling, their contractions become less forceful, so more muscle cells

must be activated to maintain a particular speed. This activation of a

larger number of muscle cells then leads to higher oxygen consumption

rates and reduced economy.

This scenario, in which slow pedaling pulls the glycogen out of

fast-twitch muscle cells, may sound paradoxical but it isn't; after

all, slow pedaling rates are linked with high gears and elevated muscle

forces, while fast cadences are associated with low gears and easy

muscle contractions. Since fast-twitch fibres are more powerful than

slow-twitch cells, the fast twitchers swing into action at slow

cadences, when high muscular forces are needed to move the bicycle

along rapidly. On the other hand, 'fast' pedaling rates of 80-100 rpm

are not too hot for the slow-twitch cells to handle. Slow-twitch cells

can contract 80-100 times per minute and can easily cope with the

forces required to pedal in low gear.

Another possible paradox in the Wisconsin Wyoming research was that

fast pedaling led to greater fat oxidation even though maximal fat

burning is usually linked with slow-paced efforts. Basically, the

higher fat degradation at 100 rpm occurred because the slow-twitch

cells handled the fast-paced, low-force contractions. Slow-twitch

fibres are much better fat-burners than their fast-twitch neighbours.

Fortunately, there's a bottom line to all this: during training and

competition, cyclists should attempt to use fast pedaling rates of

80-85 rpm, both on the flat and on inclines. Compared to slower

cadences, the higher pedaling speeds are more economical and burn more

fat during exercise. Ultimately, the high pedaling rates also preserve

greater amounts of glycogen in fast-twitch muscle fibres, leading to

more explosive 'kicks' to the finish line in closing moments of races.

\(European Journal of Applied Physiology, 1992)

******************************

My take on the study:

Cyclists over time have learned that the most efficient cadence is in

the range of 85-95 rpms. They learned this through trial and error

without the aid of scientists to tell them how fast they should pedal.

Studies such as the Wisconsin Wyoming are just trying to understand why

this cadence range is more efficient.

When I first decided to take cycling seriously and enter the

competitive arena and train for races I joined a local club with a

group of seasoned Cat II racers. As a beginner I naturally gravitated

to using big gears. It is not easy to pedal at a high cadence. I was

surprised when one of the Cat II racers took me aside and explained

that I needed to learn to use smaller gears and higher cadence. He

told me my muscles would not tire out so quickly if used the higher

cadences. He had not read this in a book or consulted scientists.

" You can't teach an old dog new tricks " . Well at age 45 I had to learn

a few new tricks. It took a long time but I learned how to pedal

fast..

[Guest guest]

There is definitely some good discussion on this topic.  As I read it, I've

started looking at it from the standpoint of burning fat vs. just burning

calories.  Please provide any insights or corrections on this, but you start

burning fat after you deplete glycogen stores,right?  If so, then a spin class

would want to put a lot of focus on the " uphill " part of the class, and probably

put that up front, or towards the front of the workout, so they can get into the

fat burning as oppose to the calorie burning and focus on fuel economy.

Just another thought, and yes, I have a lot of them.

McGrue

Fremont, CA

www.fit2start.com

________________________________

From: Ralph Giarnella <ragiarn@...>

Supertraining

Sent: Sat, November 28, 2009 4:28:00 PM

Subject: Re: Re: The effect of age on cycling Pedal Cadence

 

Boardman wrote:

Basically, as the fast fibres quickly deplete their glycogen during

slow, high-strength pedaling, their contractions become less forceful,

so more muscle cells must be activated to maintain a particular speed.

This activation of a larger number of muscle cells then leads to higher

oxygen consumption rates and reduced economy.

But in the paragraph preceding:

>>As it turned out, the athletes' oxygen consumption rates were

nearly identical in the two cases, and heart and breathing rates, total

rate of power production, and blood lactate levels were also

similar.<<

Sounds to me like the " probable explanation " is actually an hypothesis

(unproven ) that is unwarranted and unsupported by the observations.

What am I missing here?

Otherwise, the report of the study itself seems reasonable and for me, at least,

enlightening. Thanks for submitting it.

Boardman

Chicago, USA

____________ _________ _________ _

you make a good point. Unfortunately the author does not give the

title and reference for the original article so it is difficult to

track it down for specifics.

In reading his article it is important to distinguish where he stops

reporting the results of the study and begins to explain his take on

the study. I have re read the article and have attempted to

differentiate the point where he stops reporting the results and puts

in his interpretation. See if you agree.

************ ********* ********* ********* *******

Fast Pedalling: Why fast pedaling makes cyclists more efficient.

RECENTLY we reported that cyclists are usually more efficient on

both hills and flat terrain when they pedal quickly (at about 80-85

rpm) rather than at slower cadences. Now, a new study suggests that the

greater efficiency may be related to the rapid rate at which glycogen

is depleted in fast-twitch muscle fibres during slow, high-force

pedaling.

( In my opinion this is were reporting the finding of the study begins:RGMD)

To determine the actual effects of slow and fast pedaling on

leg-muscle cells, scientists at the University of Wisconsin and the

University of Wyoming asked eight experienced cyclists to cycle at an

intensity of 85% V02max for 30 minutes under two different conditions.

In one case the cyclists pedaled their bikes at 50 revolutions per

minute (rpm) while using a high gear. In the second case, the athletes

pedaled in a low gear at 100 rpm.

The athletes were traveling at Identical speeds in the two instances,

so their leg-muscle contractions were quite forceful at 50 rpm and

moderate - but more frequent - at 100 rpm.

As it turned out, the athletes' oxygen consumption rates were nearly

identical in the two cases, and heart and breathing rates, total rate

of power production, and blood lactate levels were also similar.

(this does not seem to be the authors opinion but he is reporting the

findings of the study. The fact that all the stats are similar is

important in my opinion because is shows that in both instances the

same of work was done and the same amount of energy was utilize RGMD)

However, athletes broke down the carbohydrate in their muscles at a

greater rate when the 50 rpm strategy was used, while the 100 rpm

cadence produced a greater reliance on fat. The greater glycogen

depletion at 50 rpm occurred only in fast-twitch muscle cells.

(This statement, which I believe is still reporting the original

study's finding, shows that more glycogen was used at 50 rpm than at

100 rpm. This is important for the endurance athlete because glycogen

is in limited supply and when it runs out that is when the athlete hits

the proverbial " wall " RGMD )

Slow-twitch muscle cells lost comparable amounts of their glycogen at

50 and 100 rpm, but fast-twitch cells lost almost 50 per cent of their

glycogen at 50 rpm and only 33 per cent at 100 rpm, even though the

exercise bouts lasted for 30 minutes in each case.

(This statement, which I believe is still reporting the study's

finding, is important because f the fast twitch cells lost 50% of their

glycogen after 30 min it means that the muscles will be depleted in 1

hr whereas if only 33% of glycogen is depleted the athlete will be able

to continue for 90 minutes before hitting the wall.)

In my opinion this is where reporting on the study ends and his

interpretation begins. The study would be useless unless the authors

also evaluated the source of energy in both arm of the study and how

much of each source (glycogen vs fat) was utilized.

In my opinion the study shows that while both arms of the study

produced the same amount of work what differentiates the groups is the

energy source utilized at each rpm.

(In my opinion this is where the author of the article gives his interpretations

of the study.RGMD)

This rapid loss of carbohydrate in the fast-twitch cells during slow,

high-force pedaling probably explains why slow pedaling is less

efficient than faster cadences of 80-85 rpm. Basically, as the fast

fibres quickly deplete their glycogen during slow, high-strength

pedaling, their contractions become less forceful, so more muscle cells

must be activated to maintain a particular speed. This activation of a

larger number of muscle cells then leads to higher oxygen consumption

rates and reduced economy.

This scenario, in which slow pedaling pulls the glycogen out of

fast-twitch muscle cells, may sound paradoxical but it isn't; after

all, slow pedaling rates are linked with high gears and elevated muscle

forces, while fast cadences are associated with low gears and easy

muscle contractions. Since fast-twitch fibres are more powerful than

slow-twitch cells, the fast twitchers swing into action at slow

cadences, when high muscular forces are needed to move the bicycle

along rapidly. On the other hand, 'fast' pedaling rates of 80-100 rpm

are not too hot for the slow-twitch cells to handle. Slow-twitch cells

can contract 80-100 times per minute and can easily cope with the

forces required to pedal in low gear.

Another possible paradox in the Wisconsin Wyoming research was that

fast pedaling led to greater fat oxidation even though maximal fat

burning is usually linked with slow-paced efforts. Basically, the

higher fat degradation at 100 rpm occurred because the slow-twitch

cells handled the fast-paced, low-force contractions. Slow-twitch

fibres are much better fat-burners than their fast-twitch neighbours.

Fortunately, there's a bottom line to all this: during training and

competition, cyclists should attempt to use fast pedaling rates of

80-85 rpm, both on the flat and on inclines. Compared to slower

cadences, the higher pedaling speeds are more economical and burn more

fat during exercise. Ultimately, the high pedaling rates also preserve

greater amounts of glycogen in fast-twitch muscle fibres, leading to

more explosive 'kicks' to the finish line in closing moments of races.

\(European Journal of Applied Physiology, 1992)

************ ********* *********

My take on the study:

Cyclists over time have learned that the most efficient cadence is in

the range of 85-95 rpms. They learned this through trial and error

without the aid of scientists to tell them how fast they should pedal.

Studies such as the Wisconsin Wyoming are just trying to understand why

this cadence range is more efficient.

When I first decided to take cycling seriously and enter the

competitive arena and train for races I joined a local club with a

group of seasoned Cat II racers. As a beginner I naturally gravitated

to using big gears. It is not easy to pedal at a high cadence. I was

surprised when one of the Cat II racers took me aside and explained

that I needed to learn to use smaller gears and higher cadence. He

told me my muscles would not tire out so quickly if used the higher

cadences. He had not read this in a book or consulted scientists.

" You can't teach an old dog new tricks " . Well at age 45 I had to learn

a few new tricks. It took a long time but I learned how to pedal

fast..

[Guest guest]

There is definitely some good discussion on this topic.  As I read it, I've

started looking at it from the standpoint of burning fat vs. just burning

calories.  Please provide any insights or corrections on this, but you start

burning fat after you deplete glycogen stores,right?  If so, then a spin class

would want to put a lot of focus on the " uphill " part of the class, and probably

put that up front, or towards the front of the workout, so they can get into the

fat burning as oppose to the calorie burning and focus on fuel economy.

Just another thought, and yes, I have a lot of them.

McGrue

Fremont, CA

www.fit2start.com

________________________________

From: Ralph Giarnella <ragiarn@...>

Supertraining

Sent: Sat, November 28, 2009 4:28:00 PM

Subject: Re: Re: The effect of age on cycling Pedal Cadence

 

Boardman wrote:

Basically, as the fast fibres quickly deplete their glycogen during

slow, high-strength pedaling, their contractions become less forceful,

so more muscle cells must be activated to maintain a particular speed.

This activation of a larger number of muscle cells then leads to higher

oxygen consumption rates and reduced economy.

But in the paragraph preceding:

>>As it turned out, the athletes' oxygen consumption rates were

nearly identical in the two cases, and heart and breathing rates, total

rate of power production, and blood lactate levels were also

similar.<<

Sounds to me like the " probable explanation " is actually an hypothesis

(unproven ) that is unwarranted and unsupported by the observations.

What am I missing here?

Otherwise, the report of the study itself seems reasonable and for me, at least,

enlightening. Thanks for submitting it.

Boardman

Chicago, USA

____________ _________ _________ _

you make a good point. Unfortunately the author does not give the

title and reference for the original article so it is difficult to

track it down for specifics.

In reading his article it is important to distinguish where he stops

reporting the results of the study and begins to explain his take on

the study. I have re read the article and have attempted to

differentiate the point where he stops reporting the results and puts

in his interpretation. See if you agree.

************ ********* ********* ********* *******

Fast Pedalling: Why fast pedaling makes cyclists more efficient.

RECENTLY we reported that cyclists are usually more efficient on

both hills and flat terrain when they pedal quickly (at about 80-85

rpm) rather than at slower cadences. Now, a new study suggests that the

greater efficiency may be related to the rapid rate at which glycogen

is depleted in fast-twitch muscle fibres during slow, high-force

pedaling.

( In my opinion this is were reporting the finding of the study begins:RGMD)

To determine the actual effects of slow and fast pedaling on

leg-muscle cells, scientists at the University of Wisconsin and the

University of Wyoming asked eight experienced cyclists to cycle at an

intensity of 85% V02max for 30 minutes under two different conditions.

In one case the cyclists pedaled their bikes at 50 revolutions per

minute (rpm) while using a high gear. In the second case, the athletes

pedaled in a low gear at 100 rpm.

The athletes were traveling at Identical speeds in the two instances,

so their leg-muscle contractions were quite forceful at 50 rpm and

moderate - but more frequent - at 100 rpm.

As it turned out, the athletes' oxygen consumption rates were nearly

identical in the two cases, and heart and breathing rates, total rate

of power production, and blood lactate levels were also similar.

(this does not seem to be the authors opinion but he is reporting the

findings of the study. The fact that all the stats are similar is

important in my opinion because is shows that in both instances the

same of work was done and the same amount of energy was utilize RGMD)

However, athletes broke down the carbohydrate in their muscles at a

greater rate when the 50 rpm strategy was used, while the 100 rpm

cadence produced a greater reliance on fat. The greater glycogen

depletion at 50 rpm occurred only in fast-twitch muscle cells.

(This statement, which I believe is still reporting the original

study's finding, shows that more glycogen was used at 50 rpm than at

100 rpm. This is important for the endurance athlete because glycogen

is in limited supply and when it runs out that is when the athlete hits

the proverbial " wall " RGMD )

Slow-twitch muscle cells lost comparable amounts of their glycogen at

50 and 100 rpm, but fast-twitch cells lost almost 50 per cent of their

glycogen at 50 rpm and only 33 per cent at 100 rpm, even though the

exercise bouts lasted for 30 minutes in each case.

(This statement, which I believe is still reporting the study's

finding, is important because f the fast twitch cells lost 50% of their

glycogen after 30 min it means that the muscles will be depleted in 1

hr whereas if only 33% of glycogen is depleted the athlete will be able

to continue for 90 minutes before hitting the wall.)

In my opinion this is where reporting on the study ends and his

interpretation begins. The study would be useless unless the authors

also evaluated the source of energy in both arm of the study and how

much of each source (glycogen vs fat) was utilized.

In my opinion the study shows that while both arms of the study

produced the same amount of work what differentiates the groups is the

energy source utilized at each rpm.

(In my opinion this is where the author of the article gives his interpretations

of the study.RGMD)

This rapid loss of carbohydrate in the fast-twitch cells during slow,

high-force pedaling probably explains why slow pedaling is less

efficient than faster cadences of 80-85 rpm. Basically, as the fast

fibres quickly deplete their glycogen during slow, high-strength

pedaling, their contractions become less forceful, so more muscle cells

must be activated to maintain a particular speed. This activation of a

larger number of muscle cells then leads to higher oxygen consumption

rates and reduced economy.

This scenario, in which slow pedaling pulls the glycogen out of

fast-twitch muscle cells, may sound paradoxical but it isn't; after

all, slow pedaling rates are linked with high gears and elevated muscle

forces, while fast cadences are associated with low gears and easy

muscle contractions. Since fast-twitch fibres are more powerful than

slow-twitch cells, the fast twitchers swing into action at slow

cadences, when high muscular forces are needed to move the bicycle

along rapidly. On the other hand, 'fast' pedaling rates of 80-100 rpm

are not too hot for the slow-twitch cells to handle. Slow-twitch cells

can contract 80-100 times per minute and can easily cope with the

forces required to pedal in low gear.

Another possible paradox in the Wisconsin Wyoming research was that

fast pedaling led to greater fat oxidation even though maximal fat

burning is usually linked with slow-paced efforts. Basically, the

higher fat degradation at 100 rpm occurred because the slow-twitch

cells handled the fast-paced, low-force contractions. Slow-twitch

fibres are much better fat-burners than their fast-twitch neighbours.

Fortunately, there's a bottom line to all this: during training and

competition, cyclists should attempt to use fast pedaling rates of

80-85 rpm, both on the flat and on inclines. Compared to slower

cadences, the higher pedaling speeds are more economical and burn more

fat during exercise. Ultimately, the high pedaling rates also preserve

greater amounts of glycogen in fast-twitch muscle fibres, leading to

more explosive 'kicks' to the finish line in closing moments of races.

\(European Journal of Applied Physiology, 1992)

************ ********* *********

My take on the study:

Cyclists over time have learned that the most efficient cadence is in

the range of 85-95 rpms. They learned this through trial and error

without the aid of scientists to tell them how fast they should pedal.

Studies such as the Wisconsin Wyoming are just trying to understand why

this cadence range is more efficient.

When I first decided to take cycling seriously and enter the

competitive arena and train for races I joined a local club with a

group of seasoned Cat II racers. As a beginner I naturally gravitated

to using big gears. It is not easy to pedal at a high cadence. I was

surprised when one of the Cat II racers took me aside and explained

that I needed to learn to use smaller gears and higher cadence. He

told me my muscles would not tire out so quickly if used the higher

cadences. He had not read this in a book or consulted scientists.

" You can't teach an old dog new tricks " . Well at age 45 I had to learn

a few new tricks. It took a long time but I learned how to pedal

fast..

[Guest guest]

McGrue wrote

There

is definitely some good discussion on this topic. As I read it, I've

started looking at it from the standpoint of burning fat vs.

just burning calories. Please provide any insights or corrections on

this, but you start burning fat after you deplete glycogen

stores,right? If so, then a spin class would want to put a lot of

focus on the " uphill " part of the class, and probably put that up

front, or towards the front of the workout, so they can get into the

fat burning as oppose to the calorie burning and focus on fuel economy.

Just another thought, and yes, I have a lot of them.

McGrue

Fremont, CA

www.fit2start. com

**************************************

, we need to think of fat and glucose a little differently.

Glucose is high octane fuel and is best reserved for high intensity work but it

is in limited supply. Most individuals have between 350 - 500 grams stored in

the liver and muscle. The liver stores are used to maintain a normal glucose

level in the blood. The glycogen stored in muscle fibers can only be use within

that same muscle fiber.. Muscle fibers do not share their glucose with their

neighbors. Once it is gone from the muscle fiber it needs to be obtained from

the circulation. There is not a lot of glucose floating around in the blood

(90mg/dl -less than 1 gram/liter of blood plasma). Fast Twitch (Type IIa and

IIb) are best suited to utilize glucose. Type IIb fibers with their sparse

mitochondria basically cannot use fat during exercise. Type IIa has more

mitochondria and are a better able to use fat but not as well as Type I fibers.

Fat is like diesel fuel. Not good for acceleration but good for the long haul.

There is an abundance of fat available even in individuals with low % body fat.

One pound of fat has approximately 390 grams of fat and can supply approx 3500

calories.

Fat is used for low intensity work and Slow twitch (Type I) fibers are very

efficient at utilizing fat.

During exerise the muscles use a combination of both fuels depending on the

level of intensity of the exercise and the training status of the athlete.

Below is a table of intensities of exercise and relative use of fat and glucose.

You never want to totally deplete you glucose during exerise. " Hitting the

wall " or " Bonking " is not a very pleasant feeling. Once glucose is depleted

even fat utilization becomes difficult- (the Krebs cycle slows down

dramatically).

>>>>>>>>>>>>>

Exercise Intensity & Energy Source

http://www.brianmac.co.uk/esource.htm

Energy is primarily supplied from two sources:

* Carbohydrates - in the form of glycogen stored in the muscles

* Fat - stored around the body

During exercise, we use a combination of these energy sources. At a high

intensity the main source of energy is carbohydrate and at a low intensity, fat

is the predominate source. As there is a limit to the amount of carbohydrate

that can be stored in the muscles, high intensity work can only be sustained for

short periods. We have large stores of fat so low intensity work can be

maintained for long periods.

Intensity and Energy Source

The relationship between exercise intensity (% of your Maximum Heart Rate) and

the energy source (carbohydrate and fat) is as follows:

Intensity % MHR...............% Carb.......% Fat

..........65 to 70 ....................... 40.......... 60

..........70 to 75 .........................50......... 50

..........75 to 80......................... 65..........35

..........80 to 85.........................80......... 20

..........85 to 90.........................90..........10

..........90 to 95.........................95...........5

..............100............................100..........0

Respiratory Exchange Ratio (RER)

Carbohydrates, fat and protein all play a part in energy metabolism and for a

certain volume of oxygen the energy released will depend upon the energy source.

It is possible to estimate which particular fuel (carbohydrate, fat or protein)

is being oxidised by calculating the Respiratory Exchange Ratio (RER). RER is

the ratio of carbon dioxide (CO2) produced to oxygen (O2) consumed and is known

as the Respiratory Quotient (RQ).

If carbohydrate is completely oxidised to CO2 and water (H2O) then the

relationships is as follows:

* 6O2 + C6H12O6 » 6CO2 + 6H2O + 38ATP (Adenosine Triphosphate)

* RER = 6CO2 ÷ 6O2 = 1

If fat (e.g. palmitic acid) is completely oxidised to CO2 and H2O then the

relationships is as follows:

* C16h32 + 23O2 » 16CO2 + 16H2O + 129ATP

* RER = 16CO2 ÷ 23O2 = 0.7

The RER for protein is approx. 0.8 but as it plays a very small part in energy

metabolism, it is not important here. A value between 0.7 and 1.0 indicates a

mixture of fat and carbohydrate as the energy source. A value greater than 1.0

indicates anaerobic respiration due to more CO2 being produced than O2 consumed.

***************************************

For spinning classes I would suggest a good warm up and gradually increasing

intensity to about 70-75% intsensty for the bulk of the class and finish with

5-10 min 80-85% followed by 5 minute cool down.

Total intensity for any individual workout should be determined by the goals of

the workout.

Hope this helps

Ralph Giarnella MD

Southington Ct USA

________________________________

____________ _________ _________ __

From: Ralph Giarnella <ragiarn (DOT) com>

Supertraining

Sent: Sat, November 28, 2009 4:28:00 PM

Subject: Re: Re: The effect of age on cycling Pedal Cadence

Boardman wrote:

Basically, as the fast fibres quickly deplete their glycogen during

slow, high-strength pedaling, their contractions become less forceful,

so more muscle cells must be activated to maintain a particular speed.

This activation of a larger number of muscle cells then leads to higher

oxygen consumption rates and reduced economy.

But in the paragraph preceding:

>>As it turned out, the athletes' oxygen consumption rates were

nearly identical in the two cases, and heart and breathing rates, total

rate of power production, and blood lactate levels were also

similar.<<

Sounds to me like the " probable explanation " is actually an hypothesis

(unproven ) that is unwarranted and unsupported by the observations.

What am I missing here?

Otherwise, the report of the study itself seems reasonable and for me, at least,

enlightening. Thanks for submitting it.

Boardman

Chicago, USA

____________ _________ _________ _

you make a good point. Unfortunately the author does not give the

title and reference for the original article so it is difficult to

track it down for specifics.

In reading his article it is important to distinguish where he stops

reporting the results of the study and begins to explain his take on

the study. I have re read the article and have attempted to

differentiate the point where he stops reporting the results and puts

in his interpretation. See if you agree.

************ ********* ********* ********* *******

Fast Pedalling: Why fast pedaling makes cyclists more efficient.

RECENTLY we reported that cyclists are usually more efficient on

both hills and flat terrain when they pedal quickly (at about 80-85

rpm) rather than at slower cadences. Now, a new study suggests that the

greater efficiency may be related to the rapid rate at which glycogen

is depleted in fast-twitch muscle fibres during slow, high-force

pedaling.

( In my opinion this is were reporting the finding of the study begins:RGMD)

To determine the actual effects of slow and fast pedaling on

leg-muscle cells, scientists at the University of Wisconsin and the

University of Wyoming asked eight experienced cyclists to cycle at an

intensity of 85% V02max for 30 minutes under two different conditions.

In one case the cyclists pedaled their bikes at 50 revolutions per

minute (rpm) while using a high gear. In the second case, the athletes

pedaled in a low gear at 100 rpm.

The athletes were traveling at Identical speeds in the two instances,

so their leg-muscle contractions were quite forceful at 50 rpm and

moderate - but more frequent - at 100 rpm.

As it turned out, the athletes' oxygen consumption rates were nearly

identical in the two cases, and heart and breathing rates, total rate

of power production, and blood lactate levels were also similar.

(this does not seem to be the authors opinion but he is reporting the

findings of the study. The fact that all the stats are similar is

important in my opinion because is shows that in both instances the

same of work was done and the same amount of energy was utilize RGMD)

However, athletes broke down the carbohydrate in their muscles at a

greater rate when the 50 rpm strategy was used, while the 100 rpm

cadence produced a greater reliance on fat. The greater glycogen

depletion at 50 rpm occurred only in fast-twitch muscle cells.

(This statement, which I believe is still reporting the original

study's finding, shows that more glycogen was used at 50 rpm than at

100 rpm. This is important for the endurance athlete because glycogen

is in limited supply and when it runs out that is when the athlete hits

the proverbial " wall " RGMD )

Slow-twitch muscle cells lost comparable amounts of their glycogen at

50 and 100 rpm, but fast-twitch cells lost almost 50 per cent of their

glycogen at 50 rpm and only 33 per cent at 100 rpm, even though the

exercise bouts lasted for 30 minutes in each case.

(This statement, which I believe is still reporting the study's

finding, is important because f the fast twitch cells lost 50% of their

glycogen after 30 min it means that the muscles will be depleted in 1

hr whereas if only 33% of glycogen is depleted the athlete will be able

to continue for 90 minutes before hitting the wall.)

In my opinion this is where reporting on the study ends and his

interpretation begins. The study would be useless unless the authors

also evaluated the source of energy in both arm of the study and how

much of each source (glycogen vs fat) was utilized.

In my opinion the study shows that while both arms of the study

produced the same amount of work what differentiates the groups is the

energy source utilized at each rpm.

(In my opinion this is where the author of the article gives his interpretations

of the study.RGMD)

This rapid loss of carbohydrate in the fast-twitch cells during slow,

high-force pedaling probably explains why slow pedaling is less

efficient than faster cadences of 80-85 rpm. Basically, as the fast

fibres quickly deplete their glycogen during slow, high-strength

pedaling, their contractions become less forceful, so more muscle cells

must be activated to maintain a particular speed. This activation of a

larger number of muscle cells then leads to higher oxygen consumption

rates and reduced economy.

This scenario, in which slow pedaling pulls the glycogen out of

fast-twitch muscle cells, may sound paradoxical but it isn't; after

all, slow pedaling rates are linked with high gears and elevated muscle

forces, while fast cadences are associated with low gears and easy

muscle contractions. Since fast-twitch fibres are more powerful than

slow-twitch cells, the fast twitchers swing into action at slow

cadences, when high muscular forces are needed to move the bicycle

along rapidly. On the other hand, 'fast' pedaling rates of 80-100 rpm

are not too hot for the slow-twitch cells to handle. Slow-twitch cells

can contract 80-100 times per minute and can easily cope with the

forces required to pedal in low gear.

Another possible paradox in the Wisconsin Wyoming research was that

fast pedaling led to greater fat oxidation even though maximal fat

burning is usually linked with slow-paced efforts. Basically, the

higher fat degradation at 100 rpm occurred because the slow-twitch

cells handled the fast-paced, low-force contractions. Slow-twitch

fibres are much better fat-burners than their fast-twitch neighbours.

Fortunately, there's a bottom line to all this: during training and

competition, cyclists should attempt to use fast pedaling rates of

80-85 rpm, both on the flat and on inclines. Compared to slower

cadences, the higher pedaling speeds are more economical and burn more

fat during exercise. Ultimately, the high pedaling rates also preserve

greater amounts of glycogen in fast-twitch muscle fibres, leading to

more explosive 'kicks' to the finish line in closing moments of races.

\(European Journal of Applied Physiology, 1992)

************ ********* *********

My take on the study:

Cyclists over time have learned that the most efficient cadence is in

the range of 85-95 rpms. They learned this through trial and error

without the aid of scientists to tell them how fast they should pedal.

Studies such as the Wisconsin Wyoming are just trying to understand why

this cadence range is more efficient.

When I first decided to take cycling seriously and enter the

competitive arena and train for races I joined a local club with a

group of seasoned Cat II racers. As a beginner I naturally gravitated

to using big gears. It is not easy to pedal at a high cadence. I was

surprised when one of the Cat II racers took me aside and explained

that I needed to learn to use smaller gears and higher cadence. He

told me my muscles would not tire out so quickly if used the higher

cadences. He had not read this in a book or consulted scientists.

" You can't teach an old dog new tricks " . Well at age 45 I had to learn

a few new tricks. It took a long time but I learned how to pedal

fast..

[Guest guest]

McGrue wrote

There

is definitely some good discussion on this topic. As I read it, I've

started looking at it from the standpoint of burning fat vs.

just burning calories. Please provide any insights or corrections on

this, but you start burning fat after you deplete glycogen

stores,right? If so, then a spin class would want to put a lot of

focus on the " uphill " part of the class, and probably put that up

front, or towards the front of the workout, so they can get into the

fat burning as oppose to the calorie burning and focus on fuel economy.

Just another thought, and yes, I have a lot of them.

McGrue

Fremont, CA

www.fit2start. com

**************************************

, we need to think of fat and glucose a little differently.

Glucose is high octane fuel and is best reserved for high intensity work but it

is in limited supply. Most individuals have between 350 - 500 grams stored in

the liver and muscle. The liver stores are used to maintain a normal glucose

level in the blood. The glycogen stored in muscle fibers can only be use within

that same muscle fiber.. Muscle fibers do not share their glucose with their

neighbors. Once it is gone from the muscle fiber it needs to be obtained from

the circulation. There is not a lot of glucose floating around in the blood

(90mg/dl -less than 1 gram/liter of blood plasma). Fast Twitch (Type IIa and

IIb) are best suited to utilize glucose. Type IIb fibers with their sparse

mitochondria basically cannot use fat during exercise. Type IIa has more

mitochondria and are a better able to use fat but not as well as Type I fibers.

Fat is like diesel fuel. Not good for acceleration but good for the long haul.

There is an abundance of fat available even in individuals with low % body fat.

One pound of fat has approximately 390 grams of fat and can supply approx 3500

calories.

Fat is used for low intensity work and Slow twitch (Type I) fibers are very

efficient at utilizing fat.

During exerise the muscles use a combination of both fuels depending on the

level of intensity of the exercise and the training status of the athlete.

Below is a table of intensities of exercise and relative use of fat and glucose.

You never want to totally deplete you glucose during exerise. " Hitting the

wall " or " Bonking " is not a very pleasant feeling. Once glucose is depleted

even fat utilization becomes difficult- (the Krebs cycle slows down

dramatically).

>>>>>>>>>>>>>

Exercise Intensity & Energy Source

http://www.brianmac.co.uk/esource.htm

Energy is primarily supplied from two sources:

* Carbohydrates - in the form of glycogen stored in the muscles

* Fat - stored around the body

During exercise, we use a combination of these energy sources. At a high

intensity the main source of energy is carbohydrate and at a low intensity, fat

is the predominate source. As there is a limit to the amount of carbohydrate

that can be stored in the muscles, high intensity work can only be sustained for

short periods. We have large stores of fat so low intensity work can be

maintained for long periods.

Intensity and Energy Source

The relationship between exercise intensity (% of your Maximum Heart Rate) and

the energy source (carbohydrate and fat) is as follows:

Intensity % MHR...............% Carb.......% Fat

..........65 to 70 ....................... 40.......... 60

..........70 to 75 .........................50......... 50

..........75 to 80......................... 65..........35

..........80 to 85.........................80......... 20

..........85 to 90.........................90..........10

..........90 to 95.........................95...........5

..............100............................100..........0

Respiratory Exchange Ratio (RER)

Carbohydrates, fat and protein all play a part in energy metabolism and for a

certain volume of oxygen the energy released will depend upon the energy source.

It is possible to estimate which particular fuel (carbohydrate, fat or protein)

is being oxidised by calculating the Respiratory Exchange Ratio (RER). RER is

the ratio of carbon dioxide (CO2) produced to oxygen (O2) consumed and is known

as the Respiratory Quotient (RQ).

If carbohydrate is completely oxidised to CO2 and water (H2O) then the

relationships is as follows:

* 6O2 + C6H12O6 » 6CO2 + 6H2O + 38ATP (Adenosine Triphosphate)

* RER = 6CO2 ÷ 6O2 = 1

If fat (e.g. palmitic acid) is completely oxidised to CO2 and H2O then the

relationships is as follows:

* C16h32 + 23O2 » 16CO2 + 16H2O + 129ATP

* RER = 16CO2 ÷ 23O2 = 0.7

The RER for protein is approx. 0.8 but as it plays a very small part in energy

metabolism, it is not important here. A value between 0.7 and 1.0 indicates a

mixture of fat and carbohydrate as the energy source. A value greater than 1.0

indicates anaerobic respiration due to more CO2 being produced than O2 consumed.

***************************************

For spinning classes I would suggest a good warm up and gradually increasing

intensity to about 70-75% intsensty for the bulk of the class and finish with

5-10 min 80-85% followed by 5 minute cool down.

Total intensity for any individual workout should be determined by the goals of

the workout.

Hope this helps

Ralph Giarnella MD

Southington Ct USA

________________________________

____________ _________ _________ __

From: Ralph Giarnella <ragiarn (DOT) com>

Supertraining

Sent: Sat, November 28, 2009 4:28:00 PM

Subject: Re: Re: The effect of age on cycling Pedal Cadence

Boardman wrote:

Basically, as the fast fibres quickly deplete their glycogen during

slow, high-strength pedaling, their contractions become less forceful,

so more muscle cells must be activated to maintain a particular speed.

This activation of a larger number of muscle cells then leads to higher

oxygen consumption rates and reduced economy.

But in the paragraph preceding:

>>As it turned out, the athletes' oxygen consumption rates were

nearly identical in the two cases, and heart and breathing rates, total

rate of power production, and blood lactate levels were also

similar.<<

Sounds to me like the " probable explanation " is actually an hypothesis

(unproven ) that is unwarranted and unsupported by the observations.

What am I missing here?

Otherwise, the report of the study itself seems reasonable and for me, at least,

enlightening. Thanks for submitting it.

Boardman

Chicago, USA

____________ _________ _________ _

you make a good point. Unfortunately the author does not give the

title and reference for the original article so it is difficult to

track it down for specifics.

In reading his article it is important to distinguish where he stops

reporting the results of the study and begins to explain his take on

the study. I have re read the article and have attempted to

differentiate the point where he stops reporting the results and puts

in his interpretation. See if you agree.

************ ********* ********* ********* *******

Fast Pedalling: Why fast pedaling makes cyclists more efficient.

RECENTLY we reported that cyclists are usually more efficient on

both hills and flat terrain when they pedal quickly (at about 80-85

rpm) rather than at slower cadences. Now, a new study suggests that the

greater efficiency may be related to the rapid rate at which glycogen

is depleted in fast-twitch muscle fibres during slow, high-force

pedaling.

( In my opinion this is were reporting the finding of the study begins:RGMD)

To determine the actual effects of slow and fast pedaling on

leg-muscle cells, scientists at the University of Wisconsin and the

University of Wyoming asked eight experienced cyclists to cycle at an

intensity of 85% V02max for 30 minutes under two different conditions.

In one case the cyclists pedaled their bikes at 50 revolutions per

minute (rpm) while using a high gear. In the second case, the athletes

pedaled in a low gear at 100 rpm.

The athletes were traveling at Identical speeds in the two instances,

so their leg-muscle contractions were quite forceful at 50 rpm and

moderate - but more frequent - at 100 rpm.

As it turned out, the athletes' oxygen consumption rates were nearly

identical in the two cases, and heart and breathing rates, total rate

of power production, and blood lactate levels were also similar.

(this does not seem to be the authors opinion but he is reporting the

findings of the study. The fact that all the stats are similar is

important in my opinion because is shows that in both instances the

same of work was done and the same amount of energy was utilize RGMD)

However, athletes broke down the carbohydrate in their muscles at a

greater rate when the 50 rpm strategy was used, while the 100 rpm

cadence produced a greater reliance on fat. The greater glycogen

depletion at 50 rpm occurred only in fast-twitch muscle cells.

(This statement, which I believe is still reporting the original

study's finding, shows that more glycogen was used at 50 rpm than at

100 rpm. This is important for the endurance athlete because glycogen

is in limited supply and when it runs out that is when the athlete hits

the proverbial " wall " RGMD )

Slow-twitch muscle cells lost comparable amounts of their glycogen at

50 and 100 rpm, but fast-twitch cells lost almost 50 per cent of their

glycogen at 50 rpm and only 33 per cent at 100 rpm, even though the

exercise bouts lasted for 30 minutes in each case.

(This statement, which I believe is still reporting the study's

finding, is important because f the fast twitch cells lost 50% of their

glycogen after 30 min it means that the muscles will be depleted in 1

hr whereas if only 33% of glycogen is depleted the athlete will be able

to continue for 90 minutes before hitting the wall.)

In my opinion this is where reporting on the study ends and his

interpretation begins. The study would be useless unless the authors

also evaluated the source of energy in both arm of the study and how

much of each source (glycogen vs fat) was utilized.

In my opinion the study shows that while both arms of the study

produced the same amount of work what differentiates the groups is the

energy source utilized at each rpm.

(In my opinion this is where the author of the article gives his interpretations

of the study.RGMD)

This rapid loss of carbohydrate in the fast-twitch cells during slow,

high-force pedaling probably explains why slow pedaling is less

efficient than faster cadences of 80-85 rpm. Basically, as the fast

fibres quickly deplete their glycogen during slow, high-strength

pedaling, their contractions become less forceful, so more muscle cells

must be activated to maintain a particular speed. This activation of a

larger number of muscle cells then leads to higher oxygen consumption

rates and reduced economy.

This scenario, in which slow pedaling pulls the glycogen out of

fast-twitch muscle cells, may sound paradoxical but it isn't; after

all, slow pedaling rates are linked with high gears and elevated muscle

forces, while fast cadences are associated with low gears and easy

muscle contractions. Since fast-twitch fibres are more powerful than

slow-twitch cells, the fast twitchers swing into action at slow

cadences, when high muscular forces are needed to move the bicycle

along rapidly. On the other hand, 'fast' pedaling rates of 80-100 rpm

are not too hot for the slow-twitch cells to handle. Slow-twitch cells

can contract 80-100 times per minute and can easily cope with the

forces required to pedal in low gear.

Another possible paradox in the Wisconsin Wyoming research was that

fast pedaling led to greater fat oxidation even though maximal fat

burning is usually linked with slow-paced efforts. Basically, the

higher fat degradation at 100 rpm occurred because the slow-twitch

cells handled the fast-paced, low-force contractions. Slow-twitch

fibres are much better fat-burners than their fast-twitch neighbours.

Fortunately, there's a bottom line to all this: during training and

competition, cyclists should attempt to use fast pedaling rates of

80-85 rpm, both on the flat and on inclines. Compared to slower

cadences, the higher pedaling speeds are more economical and burn more

fat during exercise. Ultimately, the high pedaling rates also preserve

greater amounts of glycogen in fast-twitch muscle fibres, leading to

more explosive 'kicks' to the finish line in closing moments of races.

\(European Journal of Applied Physiology, 1992)

************ ********* *********

My take on the study:

Cyclists over time have learned that the most efficient cadence is in

the range of 85-95 rpms. They learned this through trial and error

without the aid of scientists to tell them how fast they should pedal.

Studies such as the Wisconsin Wyoming are just trying to understand why

this cadence range is more efficient.

When I first decided to take cycling seriously and enter the

competitive arena and train for races I joined a local club with a

group of seasoned Cat II racers. As a beginner I naturally gravitated

to using big gears. It is not easy to pedal at a high cadence. I was

surprised when one of the Cat II racers took me aside and explained

that I needed to learn to use smaller gears and higher cadence. He

told me my muscles would not tire out so quickly if used the higher

cadences. He had not read this in a book or consulted scientists.

" You can't teach an old dog new tricks " . Well at age 45 I had to learn

a few new tricks. It took a long time but I learned how to pedal

fast..

[Guest guest]

On Nov 28, 2009, at 6:28:00 PM, " Ralph Giarnella " <ragiarn@...> wrote:

In my opinion this is where reporting on the study ends and his

interpretation begins. The study would be useless unless the authors

also evaluated the source of energy in both arm of the study and how

much of each source (glycogen vs fat) was utilized.

In my opinion the study shows that while both arms of the study

produced the same amount of work what differentiates the groups is the

energy source utilized at each rpm.

****

Thanks for the thought and analysis; I appreciate your effort to sort that out

and I concur with your differentiation and assumptions regarding the mix of

report and interpretation.  

Although only a recreational cyclist, I found the study to be personally

applicable and the information with justification valuable for my own

understanding and to pass on to training clients.  I also forwarded the study to

some triathlete coaches of my acquaintance.

Best wishes,

Boardman

Chicago, USA

[Guest guest]

Marshall wrote:

Phil

I believe limited experience, not age, is the likely source of your

preferred gear selection. I would suggest riding a single speed road

bike to improve your pedaling skills. I say single speed because fixed

gear bikes have a real tendency to encourage choppy pedaling despite

lore to the contrary.

-Marshall Hance

Marshall you make some excellent points in your post. The hardest skill, in my

opinion, for a newbie to learn is to spin the peddles. It takes practice and a

conscious effort to be able to sustain a high cadence. Younger riders are

better at it because, if they had a decent coach, they were taught the need to

peddle in higher cadence.

When I was coaching a Junior team (under 18) there were gear restrictions

depending on age. This was done primarily to prevent injuries to the joints

caused by pushing too big of a gear. The offshoot was that in order to go

faster they had to learn to pedal faster. A single gear bike (with coaster) will

do the trick as you pointed out. Another way to learn , if you do not have a

single gear bike, is to force yourself to stay in the small chain ring and in

the lower gears and practice peddling faster to increase speed.

I find that a good way to practice peddling faster is use a wind trainer and

make a conscious effort to engage my hamstrings as part of the peddling

sequence. Most new comers to cycling tend to just push down on the peddle stroke

(stomping) and make no effort to pull back at the bottom of the stroke.

A good coach should be able to help beginners learn how to peddle in " circles "

rather than " squares " .. I know there is a big controversy as to whether one can

actually peddle in circles but I will leave that topic for another time.

Ralph Giarnella MD

Southington Ct USA

________________________________

From: endlesscycles <endlesscycles@...>

Supertraining

Sent: Mon, November 30, 2009 5:34:35 PM

Subject: Re: The effect of age on cycling Pedal Cadence

Lower rpm's are more efficient mechanically due to lower acceleration and

deceleration of leg mass. However, as pedal force increases so do fuel robbing

reaction forces. As power increases (or leg mass decreases), so should cadence.

When applying the force/velocity concept to cadence, I would encourage

recognizing instantaneous cadence as opposed to time-averaged. A novice cyclist

might apply force at ~90rpm instantaneously, but only 70rpm time averaged

(sometimes called pedaling squares). The skilled cyclist is able to efficiently

apply force across a wider range of time-averaged cadences. As a track cyclist,

these pedaling skills are primarily important. Witness a sub 1min 1km effort!!!

Phil,

I believe limited experience, not age, is the likely source of your preferred

gear selection. I would suggest riding a single speed road bike to improve your

pedaling skills. I say single speed because fixed gear bikes have a real

tendency to encourage choppy pedaling despite lore to the contrary.

-Marshall Hance

Asheville, NC

>

> Many Masters riders contend that lower cadence and therefore higher gears is

necessary for them where younger riders can cope with higher cadence and

therefore lower gears.

>

> As a 48 year old masters track rider myself, I know that I can almost be

guaranteed of being dropped in a track race (short or long)if I ride a

comparitively low gear (say 88 gear inches) and will be far more comfortable

(and competitive) with a 92 to 94 gear inches where many of the younger riders

(under 30 years of age) are much more comfortable with lower gears and higher

cadence.

>

> I wonder about the reasons including:

> 1. Is this due to my never having learnt to ride efficiently at a high cadence

when I was younger (I only came to competitive cycling in my late 40's

> 2. Is there a physiological basis limiting high cadence in older riders e.g.

reduction in the number or efficiency of fast twitch fibres with age

> 3. It's generally accepted that cadence and heartrate are closely related and

that MHR reduces with age - So will the reduction in MHR with age be a major

factor in limiting cadence?

>

> Phil Bushell

> Melbourne Australia

>

[Guest guest]

Marshall, I think you are confusing mechanical efficiency with muscle

efficiency.

Giovanni - West Hartford, CT - USA

On Wed, Dec 2, 2009 at 11:08 AM, endlesscycles <endlesscycles@...>wrote:

>

>

> Giovanni,

>

> Acceleration and deceleration of leg mass does effect mechanical efficiency

> of the system. If you disagree, I suggest shaking your fist in the air as

> rapidly as possible. If that doesn't do it, hold something heavy and try

> again. Keep adding weight until you agree.

>

> Given the typical " Knee over pedal spindle " fitting, the idea is to use

> body weight (mostly leg mass) to directly counter the force of the pedal

> stroke. As pedal force exceeds leg mass, the weight of the rider is

> employed, which requires the core to become engaged. As pedal force exceeds

> rider mass, the muscles of the arms, shoulders, chest and back are employed

> to provide down force.

>

> When producing power on a bicycle, we select cadence to optimize the

> inefficiencies of leg speed against unnecessary muscle recruitment.

>

> Considering " pedaling circles " , if we were to directly measure torque and

> plot it against time, the oscillations of the amateur's graph may be more

> peaky than the pro's, though flat is neither possible nor even ideal. It is

> applying only tangential force on the cranks and not radial that is the true

> skill of " pedaling circles " , and is what allows the advanced rider to not

> bounce at higher rpm's.

>

> -Marshall Hance

> Asheville, NC

>

>

>

> > > >

> > > > Many Masters riders contend that lower cadence and therefore higher

> > gears is necessary for them where younger riders can cope with higher

> > cadence and therefore lower gears.

> > > >

> > > > As a 48 year old masters track rider myself, I know that I can

> > almost be guaranteed of being dropped in a track race (short or long)if

> > I ride a comparitively low gear (say 88 gear inches) and will be far

> > more comfortable (and competitive) with a 92 to 94 gear inches where

> > many of the younger riders (under 30 years of age) are much more

> > comfortable with lower gears and higher cadence.

> > > >

> > > > I wonder about the reasons including:

> > > > 1. Is this due to my never having learnt to ride efficiently at a

> > high cadence when I was younger (I only came to competitive cycling in

> > my late 40's

> > > > 2. Is there a physiological basis limiting high cadence in older

> > riders e.g. reduction in the number or efficiency of fast twitch fibres

> > with age

> > > > 3. It's generally accepted that cadence and heartrate are closely

> > related and that MHR reduces with age - So will the reduction in MHR

> > with age be a major factor in limiting cadence?

> > > >

> > > > Phil Bushell

> > > > Melbourne Australia

> > > >

> > >

> >

>

>

>

[Guest guest]

Marshall,

To answer your question " where does the wasted energy go during high rpm

efforts? "

According to the sliding-filament theory of muscle contraction (which by the

way is well documented and is a reality not just a hypothesis), the force is

totally absorbed by the friction of the sliding filaments. Hill's

Force-Velocity relationship, and the consequent Power-Velocity relationship,

depicted in the diagram at the link below, directly reflect the

sliding-filament theory. At high speed the force developed becomes zero,

therefore the power developed becomes zero.

http://www.globussht.com-a.googlepages.com/PowerVelocitycurves.JPG

As for your example of vigorously shaking your hand in the air with a weight

attached to it, it is mechanically not equivalent to a bicycle. The

deceleration of the weight is absorbed by biceps-triceps, which during the

excentric phase accomplish a negative work, which eventually turns into heat

generated by the muscle. The deceleration of the legs during high-cadence

cycling is absorbed by the fly-wheel effect of the system bike-biker whose

speed fluctuates by about 0.5% around the average speed.

Giovanni Ciriani - West Hartford, CT - USA

On Wed, Dec 2, 2009 at 9:53 PM, endlesscycles <endlesscycles@...>wrote:

>

>

> Giovanni,

>

> I recognize the semantics problem regarding muscle vs. mechanical

> efficiency. However, where does the wasted energy go during high rpm

> efforts? Is it related to an inability to relax muscles on time?

>

> -Marshall Hance

> Asheville, NC

>

>

>

> > > > > >

> > > > > > Many Masters riders contend that lower cadence and therefore

> higher

> > > > gears is necessary for them where younger riders can cope with higher

> > > > cadence and therefore lower gears.

> > > > > >

> > > > > > As a 48 year old masters track rider myself, I know that I can

> > > > almost be guaranteed of being dropped in a track race (short or

> long)if

> > > > I ride a comparitively low gear (say 88 gear inches) and will be far

> > > > more comfortable (and competitive) with a 92 to 94 gear inches where

> > > > many of the younger riders (under 30 years of age) are much more

> > > > comfortable with lower gears and higher cadence.

> > > > > >

> > > > > > I wonder about the reasons including:

> > > > > > 1. Is this due to my never having learnt to ride efficiently at a

> > > > high cadence when I was younger (I only came to competitive cycling

> in

> > > > my late 40's

> > > > > > 2. Is there a physiological basis limiting high cadence in older

> > > > riders e.g. reduction in the number or efficiency of fast twitch

> fibres

> > > > with age

> > > > > > 3. It's generally accepted that cadence and heartrate are closely

> > > > related and that MHR reduces with age - So will the reduction in MHR

> > > > with age be a major factor in limiting cadence?

> > > > > >

> > > > > > Phil Bushell

> > > > > > Melbourne Australia

> > > > > >

> > > > >

> > > >

> > >

> > >

> > >

> >

> >

> >

[Guest guest]

Giovanni wrote:

Marshall,

To answer your question " where does the wasted energy go during high rpm

efforts? "

According to the sliding-filament theory of muscle contraction (which by the

way is well documented and is a reality not just a hypothesis), the force is

totally absorbed by the friction of the sliding filaments. Hill's

Force-Velocity relationship, and the consequent Power-Velocity relationship,

depicted in the diagram at the link below, directly reflect the

sliding-filament theory. At high speed the force developed becomes zero,

therefore the power developed becomes zero.

http://www.globussh t.com-a.googlepa ges.com/PowerVel ocitycurves. JPG

As for your example of vigorously shaking your hand in the air with a weight

attached to it, it is mechanically not equivalent to a bicycle. The

deceleration of the weight is absorbed by biceps-triceps, which during the

excentric phase accomplish a negative work, which eventually turns into heat

generated by the muscle. The deceleration of the legs during high-cadence

cycling is absorbed by the fly-wheel effect of the system bike-biker whose

speed fluctuates by about 0.5% around the average speed.

Giovanni Ciriani - West Hartford, CT - USA

**************************

Giovanni, I have read your post several times and I am having difficulty

understanding how this relates to cycling cadence.

The power curves you referred to with your link show the differences between

Type I,II and III fibers and I suspect it is measuring individual fibers.

In long cycling races type I fibers are almost exclusively utilized especially

at the higher cadences whenever the intensity is below the LT threshold. Type

IIa and IIb are only recruited at intensities above LT.

At what point during the peddling cycle are you proposing that the power

generated by the leg becomes zero?

You mention a fly wheel effect- The fly wheel effect does not take place during

peddling using the normal racing bicycle gearing and set up. Could you clarify

for me what you mean by your statements?

Ralph Giarnella MD

Southington Ct USA

[Guest guest]

Ralph,

I'm glad you are asking the question, and you're right my answer was too

concise to be self explanatory.

You are right, the curves show individual fibers. However, if you sum

together all the fibers in a muscle you obtain qualitatively the same type

of Force-Velocity curve. Multiply force by velocity and you obtain the

corresponding Power-Velocity curve for the whole muscle, and eventually for

the whole limb. This is well explained by world renowned sport scientists

(1).

I believe, like you, that in long cycling races type-I fibers are

prevalently utilized; but they are not exclusively utilized. After all there

is always some fatigue developed that limits the performance of the athlete.

The longer the race, the lower the percentage o the FT fibers utilized at

any one time, and the longer it will take for a single fiber between one

utilization cycle and the next. Still the will be used.

Regardless of the mix of utilization of ST and FT fibers, there will be a

force-velocity curve for that particular mix. Let's say that you are

pedaling (not pedling) at a particular wattage and RPM that makes you

utilize 100% of your ST, and 20% of your FT type-IIa fibers. That means that

one out of five IIa fibers are contracting at any one timfe, while the other

80% are resting. Your force-velocity curve is situated between the

force-velocity curve for ST, and the force-velocity curve for FT IIa. It

will probably be closer to the ST curve, but not that much because each ST

fiber develops much less force than a FT fiber. We can debate where exactly

the curve will be situated, if we have not measured it, but it will be

somewhere in between.

You bring up another interesting point: at what point of the pedaling cycle

does the power generated by the leg become zero? Actually the curve matches

powers against speeds, and not powers against positions. The powers will

have to be a weighted average of the whole cranking cycle, because the

muscles are engaged to different extents depending at what point they are on

the 360 degrees of a cranking cycle. Nevertheless one can always measure the

wattage during a full circle and obtain the average, or measure the energy

expensed and divide by the time taken and obtain the average wattage.

Regardless of the method, there will be an average wattage corresponding to

an average speed, and this will be one point on the curve. As a matter of

fact you could use wattmeters that many professionals, elite and enthousiast

cycling athlete have and do it on your own. The data they output are

averages and are exactly what you need to trace the curve.

At what speeds is the wattage zero? One point is at speed zero; the other

point is logically at a much higher speed you would not be able to generate

on the road, but could be measured experimentally in a lab. Regardless of

the capability of measuring all the points on the curve, the important

property of the curve is that power-velocity has an inverted-U shape. This

means that unless you are using the optimal combination of speed (cadence)

and power, there will be for any given power two points: one point at higher

cadence; the other point at lower cadence. Both points will give exactly the

same fatigue and output the same power, thereby allowing the same speed on

the road (albeit at different gear ratios). There are several books (2)

explaining many of the details of force recrutiment and the force-velocity

curve better than me.

Your last question is regarding what I meant by fly wheel effect: it means

any mechanical system that stores kinetic energy (KE) and then returns it

back to the system. The wheel of the bike provides a small portion of the

fly wheel effect, then the weight of the bike and biker provides most of the

remaining portion. A mass (the thigh) attached to the pedals through another

link (the lower leg) is accelerated up and down by the pedals. As the thigh

travels down, the thigh accelerates from zero to a certain speed in the

first 90 degrees; the KE that the thigh acquires is absorbed from the KE of

the wheel and from the KE of the system bike-biker. In the next 90 degrees

the thigh decelerates from the speed it had just acquired to zero; the KE

the thigh loses is transfered back to the wheel and the bike-biker system.

Because of the magnitude of the relative speeds between thigh and bike, and

because of the relative masses between thigh and the bike-biker, a back of

the envelope calculation shows the KE exchange between the two causing a

0.5% fluctuation in speed.

(1) Citation: Force-velocity (as well as torque-angular velocity)

relationships in human movements are not identical to analogous curves of

single muscles because they are a result of the superposition of the force

outcome of several muscles possessing diffferent features. Nevertheless,

force-velocity curves registered in natural human movements can be

considered hyperbolic. The approximation is not absolutely accurate, but the

accuracy is acceptable for the practical problem of sport training.

Zatsiorsky VM, Kraemer WJ. Science and Practice of Strength Training, Second

Edition. 2nd ed. Human Kinetics Publishers; 2006.

(2) Enoka R. Neuromechanics of human movement. 4th ed. Champaign IL: Human

Kinetics; 2008.

Giovanni Ciriani - West Hartford, CT - USA

On Fri, Dec 4, 2009 at 5:38 PM, Ralph Giarnella <ragiarn@...> wrote:

>

>

> Giovanni wrote:

>

> Marshall,

> To answer your question " where does the wasted energy go during high rpm

> efforts? "

>

> According to the sliding-filament theory of muscle contraction (which by

> the

> way is well documented and is a reality not just a hypothesis), the force

> is

> totally absorbed by the friction of the sliding filaments. Hill's

> Force-Velocity relationship, and the consequent Power-Velocity

> relationship,

> depicted in the diagram at the link below, directly reflect the

> sliding-filament theory. At high speed the force developed becomes zero,

> therefore the power developed becomes zero.

> http://www.globussh t.com-a.googlepa ges.com/PowerVel ocitycurves. JPG

>

>

> As for your example of vigorously shaking your hand in the air with a

> weight

> attached to it, it is mechanically not equivalent to a bicycle. The

> deceleration of the weight is absorbed by biceps-triceps, which during the

> excentric phase accomplish a negative work, which eventually turns into

> heat

> generated by the muscle. The deceleration of the legs during high-cadence

> cycling is absorbed by the fly-wheel effect of the system bike-biker whose

> speed fluctuates by about 0.5% around the average speed.

>

> Giovanni Ciriani - West Hartford, CT - USA

> **************************

>

> Giovanni, I have read your post several times and I am having difficulty

> understanding how this relates to cycling cadence.

> The power curves you referred to with your link show the differences

> between

> Type I,II and III fibers and I suspect it is measuring individual fibers.

>

> In long cycling races type I fibers are almost exclusively utilized

> especially at the higher cadences whenever the intensity is below the LT

> threshold. Type IIa and IIb are only recruited at intensities above LT.

>

> At what point during the peddling cycle are you proposing that the power

> generated by the leg becomes zero?

>

> You mention a fly wheel effect- The fly wheel effect does not take place

> during peddling using the normal racing bicycle gearing and set up. Could

> you clarify for me what you mean by your statements?

>

>

> Ralph Giarnella MD

> Southington Ct USA

>

>

[Guest guest]

Marshall,

The uphill topic is very interesting. The greater variability of speed you

are talking about, is a phenomenon different from fly wheel. It's the

consequence of the non-uniform force produced during a pedaling 180 degree

cycle, and the steeper inclination of the curve Wattage-required vs speed.

Wattage required increases with speed because of wheel friction and air

drag. However when pedaling uphill, an additional large portion of pedaling

force goes into potential energy, i.e. the energy necessary to climb. The

additional wattage necessary for potential energy is proportional to

vertical speed (m/s) x mass of the biker (kg) x g (acceleration of gravity =

9.81 N/kg). Therefore when pedaling on the flat, a decrease in pedaling

force along the 180 degrees of cranking causes, causes a small change in

horizontal speed. When pedaling uphill, the same decrease in pedaling force

translates into a much larger variation of speed.

But the other interesting and counter intuitive fact is the following. If

one uses the same model I illustrated in my previous post (horizontal biking

cruise and power vs speed i.e. the optimal cadence), one concludes that

going uphill the cadence should be the same, albeit with a lower gear. I

know that when I go uphill I instinctively tend to pedal harder, but my

instinct doesn't make it right: I should downshift more than I do.

Giovanni Ciriani - West Hartford, CT - USA

On Sat, Dec 5, 2009 at 9:35 AM, endlesscycles <endlesscycles@...>wrote:

>

>

> Giovanni,

>

> I recognize the flywheel effect to be that for pedal speeds that do not

> keep up the the drivetrain, pedaling force is actually less than zero. Like

> Ralph, I have a hard time visualizing or experiencing the reciprocating

> momentum such that the leg/crank system should continue to spin when

> unloaded without muscular interference. I'm glad you pointed it out, and I

> realize it to be true even though it is very hard to imagine based on

> experience alone.

>

> When you suggested the system speed fluctuates only .5% about average speed

> I believe you inadvertently hit on something interesting.

> System speed variability actually increases up hills and significantly

> stabilizes down hills (or in a paceline) which would suggest that there is a

> difference in muscle usage depending on grade. It would to me suggest higher

> cadences when climbing and lower cadence when speed is stabilized. I also

> now realize the importance of training on grades expected in the race.

>

>

> -Marshall Hance

> Asheville, NC

>

>

> > > > > > > >

> > > > > > > > Many Masters riders contend that lower cadence and therefore

> > > higher

> > > > > > gears is necessary for them where younger riders can cope with

> higher

> > > > > > cadence and therefore lower gears.

> > > > > > > >

> > > > > > > > As a 48 year old masters track rider myself, I know that I

> can

> > > > > > almost be guaranteed of being dropped in a track race (short or

> > > long)if

> > > > > > I ride a comparitively low gear (say 88 gear inches) and will be

> far

> > > > > > more comfortable (and competitive) with a 92 to 94 gear inches

> where

> > > > > > many of the younger riders (under 30 years of age) are much more

> > > > > > comfortable with lower gears and higher cadence.

> > > > > > > >

> > > > > > > > I wonder about the reasons including:

> > > > > > > > 1. Is this due to my never having learnt to ride efficiently

> at a

> > > > > > high cadence when I was younger (I only came to competitive

> cycling

> > > in

> > > > > > my late 40's

> > > > > > > > 2. Is there a physiological basis limiting high cadence in

> older

> > > > > > riders e.g. reduction in the number or efficiency of fast twitch

> > > fibres

> > > > > > with age

> > > > > > > > 3. It's generally accepted that cadence and heartrate are

> closely

> > > > > > related and that MHR reduces with age - So will the reduction in

> MHR

> > > > > > with age be a major factor in limiting cadence?

> > > > > > > >

> > > > > > > > Phil Bushell

> > > > > > > > Melbourne Australia

> > > > > > > >

> > > > > > >

> > > > > >

> > > > >

> > > > >

> > > > >

> > > >

> > > >

> > > >

[Guest guest]

Giovanni wrote:

Marshall,

The uphill topic is very interesting. The greater variability of speed you

are talking about, is a phenomenon different from fly wheel. It's the

consequence of the non-uniform force produced during a pedaling 180 degree

cycle, and the steeper inclination of the curve Wattage-required vs speed.

Wattage required increases with speed because of wheel friction and air

drag. However when pedaling uphill, an additional large portion of pedaling

force goes into potential energy, i.e. the energy necessary to climb. The

additional wattage necessary for potential energy is proportional to

vertical speed (m/s) x mass of the biker (kg) x g (acceleration of gravity =

9.81 N/kg). Therefore when pedaling on the flat, a decrease in pedaling

force along the 180 degrees of cranking causes, causes a small change in

horizontal speed. When pedaling uphill, the same decrease in pedaling force

translates into a much larger variation of speed.

But the other interesting and counter intuitive fact is the following. If

one uses the same model I illustrated in my previous post (horizontal biking

cruise and power vs speed i.e. the optimal cadence), one concludes that

going uphill the cadence should be the same, albeit with a lower gear. I

know that when I go uphill I instinctively tend to pedal harder, but my

instinct doesn't make it right: I should downshift more than I do.

Giovanni Ciriani - West Hartford, CT - USA

On Sat, Dec 5, 2009 at 9:35 AM, endlesscycles <endlesscycles>wrote:

**************************

Giovanni, I would like to comment on a few points you made.

You are making reference to peddling 180deg- I assume you are referring to each

leg contributing 180 deg of the full cycle. However while that my be true of

newbies to cycling it is not true of the experienced cyclist.

To Illustrate, the next time you are out on your bike or if you are on a wind

trainer at home try the following.

Detach the left foot from its peddle while coasting. Push down with the right

foot from 12:00 to 6:00-(180 deg). What happens? The right foot remains at 6:00

and the bike continues to travel forward (or in the case of a bike on a wind

trainer) the rear wheel continues to spin.

There is no fly wheel effect. For the right leg to return back to the original

12:00 position to start the next cycle one of two things has to occur.

1) you put your left foot back on the left peddle and push own and in this

manner you push your right foot and leg back up or

2) You actively engage other muscles in your right leg to pull back and up your

foot (as in trying to scrape mud off your shoe).

In #1 your left leg has to do more work with some of the work being dedicated

to lifting the right leg and the rest to propelling the bike forward.

In #2 the right leg is working to lift the right peddle thus allowing more of

the force from the left leg to be dedicated to propelling the bike forward. In

this manner the right leg is contributing more than 180deg to the full cycle.

The act of pulling through and lifting is called " off loading " .

In experienced cyclists this may be as much as 270deg under certain

circumstances. It takes a lot of concentration and dedication to learn this

technique. It does not come naturally.

If this is done correctly there is minimal if any slowing of the cycle at any

point. This is called peddling in circles. The beginner tends to stomp on the

peddles (peddling in squares). As a result there is a dead spot in the cycle.

In riding uphill it is not only important to shift to lower gears to keep the

cadence high for as long as possible but also to shift your weight further back

on the saddle, to aid in the pulling back on the peddle. Done correctly you will

feel your hamstrings begin to burn.

What we have lost sight of in this discussion is why is peddling in the 85-95

rpm more efficient energy wise for the endurance cyclists. I alluded to that in

my previous posts. The mistake often made is to assume that to peddle faster

you need to engage TypII (a/b)fibers.

The endurance cyclists tries to use Type II fibers sparingly and judiciously

throughout the race.

Ralph Giarnella MD

Southington Ct USA

>

>

> Giovanni,

>

> I recognize the flywheel effect to be that for pedal speeds that do not

> keep up the the drivetrain, pedaling force is actually less than zero. Like

> Ralph, I have a hard time visualizing or experiencing the reciprocating

> momentum such that the leg/crank system should continue to spin when

> unloaded without muscular interference. I'm glad you pointed it out, and I

> realize it to be true even though it is very hard to imagine based on

> experience alone.

>

> When you suggested the system speed fluctuates only .5% about average speed

> I believe you inadvertently hit on something interesting.

> System speed variability actually increases up hills and significantly

> stabilizes down hills (or in a paceline) which would suggest that there is a

> difference in muscle usage depending on grade. It would to me suggest higher

> cadences when climbing and lower cadence when speed is stabilized. I also

> now realize the importance of training on grades expected in the race.

>

>

> -Marshall Hance

> Asheville, NC

>

>

> > > > > > > >

> > > > > > > > Many Masters riders contend that lower cadence and therefore

> > > higher

> > > > > > gears is necessary for them where younger riders can cope with

> higher

> > > > > > cadence and therefore lower gears.

> > > > > > > >

> > > > > > > > As a 48 year old masters track rider myself, I know that I

> can

> > > > > > almost be guaranteed of being dropped in a track race (short or

> > > long)if

> > > > > > I ride a comparitively low gear (say 88 gear inches) and will be

> far

> > > > > > more comfortable (and competitive) with a 92 to 94 gear inches

> where

> > > > > > many of the younger riders (under 30 years of age) are much more

> > > > > > comfortable with lower gears and higher cadence.

> > > > > > > >

> > > > > > > > I wonder about the reasons including:

> > > > > > > > 1. Is this due to my never having learnt to ride efficiently

> at a

> > > > > > high cadence when I was younger (I only came to competitive

> cycling

> > > in

> > > > > > my late 40's

> > > > > > > > 2. Is there a physiological basis limiting high cadence in

> older

> > > > > > riders e.g. reduction in the number or efficiency of fast twitch

> > > fibres

> > > > > > with age

> > > > > > > > 3. It's generally accepted that cadence and heartrate are

> closely

> > > > > > related and that MHR reduces with age - So will the reduction in

> MHR

> > > > > > with age be a major factor in limiting cadence?

> > > > > > > >

> > > > > > > > Phil Bushell

> > > > > > > > Melbourne Australia

> > > > > > > >

> > > > > > >

> > > > > >

> > > > >

> > > > >

> > > > >

> > > >

> > > >

> > > >

[Guest guest]

Ralph,

The flywheel effect I described has nothing to do with muscle contraction.

You may pedal with a very refined technique, which you described in your

post, or you may pedal as an untrained newbie, then on top of those forces

you have to still add the exchange of kinetic energy (KE) between moving

legs and bike. As a matter of fact you could have pieces of metal or wood

simulating the leg, and you still would have a flywheel effect, exchanging

KE between the fake legs and the rest of the contraption. I limited the

explanation to 180 degrees because by looking at both legs at the same time,

the motion repeats identically every 180 degrees.

Your observation regarding uphill - modifying the poststure and hamstring

that start burning - is extremely interesting. Is your observation that the

quads engage harder or not? How do you know when you have downshifted enough

going uphill?

I agree that for any cycling athlete there must be an optimal cadence. From

what I've read around in other forums, it's different for every athlete.

What I don't know is if everybody's optimal cadence falls within the

85-95-rpm range, or if there are individuals who may fall outside of it.

P.S.

Recent research (last 10 years) has shown that in humans we have to talk

about type IIx fibers, not IIb, and what older studies were considering IIb

were in effect IIx.

PPS

Pleased forgive the correction from a non mother tongue writer. I'm sure I

make plenty of ortographic mistakes in my comments. However, it's pedal, not

peddle, which means selling or offer for sale from place to place.

Giovanni Ciriani - West Hartford, CT - USA

On Sun, Dec 6, 2009 at 6:58 PM, Ralph Giarnella <ragiarn@...> wrote:

>

> On Sat, Dec 5, 2009 at 9:35 AM, endlesscycles <endlesscycles

> >wrote:

> **************************

> Giovanni, I would like to comment on a few points you made.

> You are making reference to peddling 180deg- I assume you are referring to

> each leg contributing 180 deg of the full cycle. However while that my be

> true of newbies to cycling it is not true of the experienced cyclist.

>

> To Illustrate, the next time you are out on your bike or if you are on a

> wind trainer at home try the following.

>

> Detach the left foot from its peddle while coasting. Push down with the

> right foot from 12:00 to 6:00-(180 deg). What happens? The right foot

> remains at 6:00 and the bike continues to travel forward (or in the case of

> a bike on a wind trainer) the rear wheel continues to spin.

>

> There is no flywheel effect. For the right leg to return back to the

> original 12:00 position to start the next cycle one of two things has to

> occur.

>

> 1) you put your left foot back on the left peddle and push own and in this

> manner you push your right foot and leg back up or

>

> 2) You actively engage other muscles in your right leg to pull back and up

> your foot (as in trying to scrape mud off your shoe).

> In #1 your left leg has to do more work with some of the work being

> dedicated to lifting the right leg and the rest to propelling the bike

> forward.

> In #2 the right leg is working to lift the right peddle thus allowing more

> of the force from the left leg to be dedicated to propelling the bike

> forward. In this manner the right leg is contributing more than 180deg to

> the full cycle. The act of pulling through and lifting is called " off

> loading " .

>

> In experienced cyclists this may be as much as 270deg under certain

> circumstances. It takes a lot of concentration and dedication to learn this

> technique. It does not come naturally.

> If this is done correctly there is minimal if any slowing of the cycle at

> any point. This is called peddling in circles. The beginner tends to stomp

> on the peddles (peddling in squares). As a result there is a dead spot in

> the cycle.

>

> In riding uphill it is not only important to shift to lower gears to keep

> the cadence high for as long as possible but also to shift your weight

> further back on the saddle, to aid in the pulling back on the peddle. Done

> correctly you will feel your hamstrings begin to burn.

> What we have lost sight of in this discussion is why is peddling in the

> 85-95 rpm more efficient energy wise for the endurance cyclists. I alluded

> to that in my previous posts. The mistake often made is to assume that to

> peddle faster you need to engage TypII (a/b)fibers.

> The endurance cyclists tries to use Type II fibers sparingly and

> judiciously throughout the race.

> Ralph Giarnella MD

> Southington Ct USA

>

> >

> >

[Guest guest]

________________________________

From: Giovanni Ciriani <Giovanni.Ciriani@...>

Supertraining

Sent: Mon, December 7, 2009 9:28:46 AM

Subject: Re: Re: The effect of age on cycling Pedal Cadence

Ralph,

The flywheel effect I described has nothing to do with muscle contraction.

You may pedal with a very refined technique, which you described in your

post, or you may pedal as an untrained newbie, then on top of those forces

you have to still add the exchange of kinetic energy (KE) between moving

legs and bike. As a matter of fact you could have pieces of metal or wood

simulating the leg, and you still would have a flywheel effect, exchanging

KE between the fake legs and the rest of the contraption. I limited the

explanation to 180 degrees because by looking at both legs at the same time,

the motion repeats identically every 180 degrees

******

Giovanni,

I am trying to understand where this flywheel effect you mention occurs. It

certainly is not in the pedals or chain rings.

RG

************************

Giovanni wrote:

Your observation regarding uphill - modifying the poststure and hamstring

that start burning - is extremely interesting. Is your observation that the

quads engage harder or not? How do you know when you have downshifted enough

going uphill?

**************

Ideally the cyclist would maintain the same effort uphill as on the flats. By

moving further back in the saddle the hamstrings are better able to assist in

pedaling. The ideal bike for climbing hills has a different configuration than

the ideal bike for sprinting. The seat tube of the hill climbing bike is angled

back further. Professionals have several bikes depending on the terrain and

type of racing.

RG.

**********************

Giovanni wrote:

I agree that for any cycling athlete there must be an optimal cadence. From

what I've read around in other forums, it's different for every athlete.

What I don't know is if everybody's optimal cadence falls within the

85-95-rpm range, or if there are individuals who may fall outside of it.

***************

There is a difference between what is optimal rpm and what the rpm the athlete

has become accustomed to using. The bigger the gear and therefore the lower the

cadence requires greater force/pedal stroke. As a result requiring more of the

IIa and IIb fibers. The IIa and IIb fibers fatigue more easily than Type I and

are generally used for short bursts of energy. If an individual is involved in

a short race (1-2 hrs) they may be able to use more of the Type IIa fibers.

For longer races they would want to reserve those fibers for special situations

such as the final sprint, bridging a gap, or a sudden surge in speed. When

referring to the type II fibers coaches often use the analogy of matches. The

athete start the race just so many matches to burn. Once they are used up they

cannot be readily replenished.

Using the higher gearing (85-95 rpms) allows greater reliance on Type I fibers

which are not easily fatigued and if properly trained go on forever.

I will let some one else explain it better:

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

" Training High Pedaling Cadence

By: Michele Ferrari

Published: 10 Mar 2003

The Art of Spinning... Read about the concepts and advantages of having a high

pedaling cadence while training/racing.

Pedaling at 60 RPM (revolutions per minute) or at 90 RPM during an uphill

course: what are the effects on performance, tiredness and recovery?

At 60 RPM it takes 1.0 second for the crank to make a complete revolution

(360º), at 90 RPM it only takes 0.66 seconds that is 34% less.

The contraction time of the muscles involved in pedaling, decrease thus of that

same percentage.

During the muscle contraction phase, blood flow (and so the oxygen carrying) to

the single fiber, especially the most profound ones, lessens because of the

increased pressure within the working muscles.

Moreover, in terms of equal power output supplied by the cyclist, a cadence of

60 RPM requires a 34% more of applied force to each push on the pedals, compared

to a cadence of 90 RPM. This means a heavier load for muscles, tendons and lower

limbs-lumbar joints.

It is easy to realize the advantages of a more “agile†pedaling cadence,

especially when the rider is busy with an all-out effort, as soon as the oxygen

carrying becomes the limiting factor of his performance.

Also the recovery between 2 or more efforts, within just one training session or

race, or even within the next days, takes advantage from an agile pedaling

cadence, whereas the risk of injuries or overworking lesions increases with

lower RPMs.

A high pedaling cadence also improves the pumping function of skeletal muscles,

the most important factor in defining systemic venous return of the blood to the

heart.

This peripheral pump plays a critical role in circulatory functional

capacity, and can be viewed as a second heart.

In conclusion, high pedaling cadences are favorable to riders, as demonstrated

by the examples of great champions such as Indurain and Lance Armstrong.

A very long training as well as specific sessions are needed in order to learn

how to pedal comfortably and profitably at high cadences, particularly during

climbs: but that is a different story

***************************************************************

Giovanni wrote:

P.S.

Recent research (last 10 years) has shown that in humans we have to talk

about type IIx fibers, not IIb, and what older studies were considering IIb

were in effect IIx.

*********************************************

Depending on who you read the IIx fibers are considered undifferentiated fibers

and sometimes referred to as IIc fibers.

RGMD

*********************

Dr. Seiler PHD- well known and published exercise physiologist (who also

actively competes in master rowing) writes

Fiber Types

Fiber functional properties, peak force, contraction velocity, resistance to

fatigue, oxidative and glycolytic capacities, and actino-myosin ATPase

activities, fall across a broad spectrum. Nonetheless, it is possible to divide

this continuum into a few clusters.

Based on observations of the contractile properties of motor units (force,

velocity and fatiguability), Burke and coworkers created four motor unit types.

Histochemical assays of the motor unit fibers striking similarites within a

unit.

Slow

The most distinct type had long twitch times, low peak forces and high

resistance to fatigue. Biochemically, these fibers were found to be high in

oxidative enzymes, but low in glycolytic markers and ATPase activity. These have

been termed " slow " fibers.

Fast, Fatigue Resistant

Of the fibers with faster contraction times, some were found to maintain their

force production even after a large number of contractions. They tend to be high

in oxidative and glycolytic enzymes and ATPase activity. These have been termed

Fast Resistant (FR) or (histochemically) Fast Oxidative-Glycolytic (FOG).

Fast Fatiguable

The last clearly definable group displayed high contraction rates and extremely

large forces, but was unable to maintain these tensions for more than a few

contractions without rest. These properties correlated with high ATPase and

glycolytic activities and low oxidative capacity. These have been termed Fast

Fatiguable (FF) or Fast Glycolytic (FG) fibers.

http://muscle.ucsd.edu/musintro/fiber.shtml

Fast Intermediate

Basically a catch-all group for a small number of fibers that didn't clearly

belong to the other fast groups. These fibers have fast contraction times and

maintain some, though not a great amount of their force production with repeated

activity.

There are at least nine different mammalian MHC isoforms. Two are developmental,

termed embryonic and neonatal, based on the time of their expression. Two are

" slow " forms, expressed in the heart and termed cardiac alpha and beta. The

cardiac beta is also found in slow skeletal muscle fibers (in which case it is

called type 1). The remaining forms are found in fast skeletal muscle. Type 2a

is found in most FOG fibers, and type 2b and 2x in FG fibers. The last two are

relatively rare and appears to be expressed primarily in the extraocular,

laryngial and jaw muscles

********************

Giovanni writes:

PPS

Pleased forgive the correction from a non mother tongue writer. I'm sure I

make plenty of ortographic mistakes in my comments. However, it's pedal, not

peddle, which means selling or offer for sale from place to place.

*************************************************

I realized the mistake after I posted- need to do a better job of proof-reading.

Ralph Giarnella MD

Southington Ct USA

On Sun, Dec 6, 2009 at 6:58 PM, Ralph Giarnella <ragiarn (DOT) com> wrote:

>

> On Sat, Dec 5, 2009 at 9:35 AM, endlesscycles <endlesscycles

> >wrote:

> ************ ********* *****

> Giovanni, I would like to comment on a few points you made.

> You are making reference to peddling 180deg- I assume you are referring to

> each leg contributing 180 deg of the full cycle. However while that my be

> true of newbies to cycling it is not true of the experienced cyclist.

>

> To Illustrate, the next time you are out on your bike or if you are on a

> wind trainer at home try the following.

>

> Detach the left foot from its peddle while coasting. Push down with the

> right foot from 12:00 to 6:00-(180 deg). What happens? The right foot

> remains at 6:00 and the bike continues to travel forward (or in the case of

> a bike on a wind trainer) the rear wheel continues to spin.

>

> There is no flywheel effect. For the right leg to return back to the

> original 12:00 position to start the next cycle one of two things has to

> occur.

>

> 1) you put your left foot back on the left peddle and push own and in this

> manner you push your right foot and leg back up or

>

> 2) You actively engage other muscles in your right leg to pull back and up

> your foot (as in trying to scrape mud off your shoe).

> In #1 your left leg has to do more work with some of the work being

> dedicated to lifting the right leg and the rest to propelling the bike

> forward.

> In #2 the right leg is working to lift the right peddle thus allowing more

> of the force from the left leg to be dedicated to propelling the bike

> forward. In this manner the right leg is contributing more than 180deg to

> the full cycle. The act of pulling through and lifting is called " off

> loading " .

>

> In experienced cyclists this may be as much as 270deg under certain

> circumstances. It takes a lot of concentration and dedication to learn this

> technique. It does not come naturally.

> If this is done correctly there is minimal if any slowing of the cycle at

> any point. This is called peddling in circles. The beginner tends to stomp

> on the peddles (peddling in squares). As a result there is a dead spot in

> the cycle.

>

> In riding uphill it is not only important to shift to lower gears to keep

> the cadence high for as long as possible but also to shift your weight

> further back on the saddle, to aid in the pulling back on the peddle. Done

> correctly you will feel your hamstrings begin to burn.

> What we have lost sight of in this discussion is why is peddling in the

> 85-95 rpm more efficient energy wise for the endurance cyclists. I alluded

> to that in my previous posts. The mistake often made is to assume that to

> peddle faster you need to engage TypII (a/b)fibers.

> The endurance cyclists tries to use Type II fibers sparingly and

> judiciously throughout the race.

> Ralph Giarnella MD

> Southington Ct USA

>

> >

> >

[Guest guest]

Ralph,

To help you understand the flywheel effect: as the leg travels down the

vertical speed of the thigh goes from a certain value to zero. The

deceleration is caused by an opposite reaction of the pedal to, which is

then transferred to wheel and increases the speed of the bike by 0.5%.

Thanks for explaining that there are different types of bikes for climbing

etc. But I repeat my questions: Is your observation that the quads engage

harder or not? How do you know when you have downshifted enough

going uphill?

As I said before, I agree about the different usage of different fiber

types, and why it makes sense. However, the passage from Michele Ferrari

doesn't address where do we stop for an optimal rpm cadence. If I, you and

Ferrari e just followed the circular reasoning that faster pedaling was

better, than 100 rpm would be better than 90 rpm, 110 rpm would be better

than 100 rpm and so on, ad infinitum. There must be a speed where the gain

in using type I fibers is completely offset by some other types of loss

(sliding filament theory). And non of these authors seem to address it. I

postulate that even for the same athlete different power output have each

different optimal rpm.

The passage on IIb you cited is dated. I'll be glad to lend you the

following 2000 paper* from which I cite:

In this way the histological identification of three main human muscle fibre

types (I, IIA and IIX, previously called IIB) has been followed by a precise

description of molecular composition and functional and biochemical

properties. ...

In this review the MHC isoform composition will be adopted as the criteria

for fibre classification. To be fully consistent with this choice the fibres

containing MHC-IIX will be identified as IIX fibres, despite the fact that

most papers have used in the past and still use now the term IIB fibres. No

fibres containing MHC-IIB have been until now found in human muscles

although the gene coding for this isoform is present in the human genome and

has

been localized on chromosome 17.

Note*:

Bottinelli R, Reggiani C. Human skeletal muscle fibres: molecular and

functional diversity. Progress in Biophysics and Molecular Biology.

2000;73(2-4):195-262.

Giovanni Ciriani - West Hartford, CT - USA

On Mon, Dec 7, 2009 at 6:03 PM, Ralph Giarnella <ragiarn@...> wrote:

>

>

>

>

> ________________________________

> From: Giovanni Ciriani

<Giovanni.Ciriani@...<Giovanni.Ciriani%40Gmail.com>

> >

> Supertraining <Supertraining%40>

> Sent: Mon, December 7, 2009 9:28:46 AM

> Subject: Re: Re: The effect of age on cycling Pedal Cadence

>

>

> Ralph,

> The flywheel effect I described has nothing to do with muscle contraction.

> You may pedal with a very refined technique, which you described in your

> post, or you may pedal as an untrained newbie, then on top of those forces

> you have to still add the exchange of kinetic energy (KE) between moving

> legs and bike. As a matter of fact you could have pieces of metal or wood

> simulating the leg, and you still would have a flywheel effect, exchanging

> KE between the fake legs and the rest of the contraption. I limited the

> explanation to 180 degrees because by looking at both legs at the same

> time,

> the motion repeats identically every 180 degrees

> ******

> Giovanni,

> I am trying to understand where this flywheel effect you mention occurs. It

> certainly is not in the pedals or chain rings.

>

> RG

> ************************

>

>

> Giovanni wrote:

> Your observation regarding uphill - modifying the poststure and hamstring

> that start burning - is extremely interesting. Is your observation that the

> quads engage harder or not? How do you know when you have downshifted

> enough

> going uphill?

> **************

> Ideally the cyclist would maintain the same effort uphill as on the flats.

> By moving further back in the saddle the hamstrings are better able to

> assist in pedaling. The ideal bike for climbing hills has a different

> configuration than the ideal bike for sprinting. The seat tube of the hill

> climbing bike is angled back further. Professionals have several bikes

> depending on the terrain and type of racing.

>

> RG.

>

> **********************

>

> Giovanni wrote:

> I agree that for any cycling athlete there must be an optimal cadence. From

> what I've read around in other forums, it's different for every athlete.

> What I don't know is if everybody's optimal cadence falls within the

> 85-95-rpm range, or if there are individuals who may fall outside of it.

> ***************

> There is a difference between what is optimal rpm and what the rpm the

> athlete has become accustomed to using. The bigger the gear and therefore

> the lower the cadence requires greater force/pedal stroke. As a result

> requiring more of the IIa and IIb fibers. The IIa and IIb fibers fatigue

> more easily than Type I and are generally used for short bursts of energy.

> If an individual is involved in a short race (1-2 hrs) they may be able to

> use more of the Type IIa fibers. For longer races they would want to reserve

> those fibers for special situations such as the final sprint, bridging a

> gap, or a sudden surge in speed. When referring to the type II fibers

> coaches often use the analogy of matches. The athete start the race just so

> many matches to burn. Once they are used up they cannot be readily

> replenished.

> Using the higher gearing (85-95 rpms) allows greater reliance on Type I

> fibers which are not easily fatigued and if properly trained go on forever.

>

> I will let some one else explain it better:

> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

> " Training High Pedaling Cadence

> By: Michele Ferrari

> Published: 10 Mar 2003

>

> The Art of Spinning... Read about the concepts and advantages of having a

> high pedaling cadence while training/racing.

>

> Pedaling at 60 RPM (revolutions per minute) or at 90 RPM during an uphill

> course: what are the effects on performance, tiredness and recovery?

>

> At 60 RPM it takes 1.0 second for the crank to make a complete revolution

> (360º), at 90 RPM it only takes 0.66 seconds that is 34% less.

>

> The contraction time of the muscles involved in pedaling, decrease thus of

> that same percentage.

> During the muscle contraction phase, blood flow (and so the oxygen

> carrying) to the single fiber, especially the most profound ones, lessens

> because of the increased pressure within the working muscles.

>

> Moreover, in terms of equal power output supplied by the cyclist, a cadence

> of 60 RPM requires a 34% more of applied force to each push on the pedals,

> compared to a cadence of 90 RPM. This means a heavier load for muscles,

> tendons and lower limbs-lumbar joints.

>

> It is easy to realize the advantages of a more “agile” pedaling cadence,

> especially when the rider is busy with an all-out effort, as soon as the

> oxygen carrying becomes the limiting factor of his performance.

>

> Also the recovery between 2 or more efforts, within just one training

> session or race, or even within the next days, takes advantage from an agile

> pedaling cadence, whereas the risk of injuries or overworking lesions

> increases with lower RPMs.

>

> A high pedaling cadence also improves the pumping function of skeletal

> muscles, the most important factor in defining systemic venous return of the

> blood to the heart.

> This peripheral pump plays a critical role in circulatory functional

> capacity, and can be viewed as a second heart.

>

> In conclusion, high pedaling cadences are favorable to riders, as

> demonstrated by the examples of great champions such as Indurain and

> Lance Armstrong.

>

> A very long training as well as specific sessions are needed in order to

> learn how to pedal comfortably and profitably at high cadences, particularly

> during climbs: but that is a different story

> ***************************************************************

>

>

> Giovanni wrote:

>

> P.S.

> Recent research (last 10 years) has shown that in humans we have to talk

> about type IIx fibers, not IIb, and what older studies were considering IIb

> were in effect IIx.

> *********************************************

>

> Depending on who you read the IIx fibers are considered undifferentiated

> fibers and sometimes referred to as IIc fibers.

> RGMD

>

> *********************

> Dr. Seiler PHD- well known and published exercise physiologist (who

> also actively competes in master rowing) writes

> Fiber Types

>

> Fiber functional properties, peak force, contraction velocity, resistance

> to fatigue, oxidative and glycolytic capacities, and actino-myosin ATPase

> activities, fall across a broad spectrum. Nonetheless, it is possible to

> divide this continuum into a few clusters.

>

> Based on observations of the contractile properties of motor units (force,

> velocity and fatiguability), Burke and coworkers created four motor unit

> types. Histochemical assays of the motor unit fibers striking similarites

> within a unit.

>

> Slow

> The most distinct type had long twitch times, low peak forces and high

> resistance to fatigue. Biochemically, these fibers were found to be high in

> oxidative enzymes, but low in glycolytic markers and ATPase activity. These

> have been termed " slow " fibers.

>

> Fast, Fatigue Resistant

> Of the fibers with faster contraction times, some were found to maintain

> their force production even after a large number of contractions. They tend

> to be high in oxidative and glycolytic enzymes and ATPase activity. These

> have been termed Fast Resistant (FR) or (histochemically) Fast

> Oxidative-Glycolytic (FOG).

>

> Fast Fatiguable

> The last clearly definable group displayed high contraction rates and

> extremely large forces, but was unable to maintain these tensions for more

> than a few contractions without rest. These properties correlated with high

> ATPase and glycolytic activities and low oxidative capacity. These have been

> termed Fast Fatiguable (FF) or Fast Glycolytic (FG) fibers.

> http://muscle.ucsd.edu/musintro/fiber.shtml

>

> Fast Intermediate

> Basically a catch-all group for a small number of fibers that didn't

> clearly belong to the other fast groups. These fibers have fast contraction

> times and maintain some, though not a great amount of their force production

> with repeated activity.

>

> There are at least nine different mammalian MHC isoforms. Two are

> developmental, termed embryonic and neonatal, based on the time of their

> expression. Two are " slow " forms, expressed in the heart and termed cardiac

> alpha and beta. The cardiac beta is also found in slow skeletal muscle

> fibers (in which case it is called type 1). The remaining forms are found in

> fast skeletal muscle. Type 2a is found in most FOG fibers, and type 2b and

> 2x in FG fibers. The last two are relatively rare and appears to be

> expressed primarily in the extraocular, laryngial and jaw muscles

>

> ********************

>

> Giovanni writes:

>

> PPS

> Pleased forgive the correction from a non mother tongue writer. I'm sure I

> make plenty of ortographic mistakes in my comments. However, it's pedal,

> not

> peddle, which means selling or offer for sale from place to place.

> *************************************************

>

> I realized the mistake after I posted- need to do a better job of

> proof-reading.

>

> Ralph Giarnella MD

> Southington Ct USA

> On Sun, Dec 6, 2009 at 6:58 PM, Ralph Giarnella <ragiarn (DOT) com>

> wrote:

>

> >

> > On Sat, Dec 5, 2009 at 9:35 AM, endlesscycles <endlesscycles

> > >wrote:

> > ************ ********* *****

> > Giovanni, I would like to comment on a few points you made.

> > You are making reference to peddling 180deg- I assume you are referring

> to

> > each leg contributing 180 deg of the full cycle. However while that my be

> > true of newbies to cycling it is not true of the experienced cyclist.

> >

> > To Illustrate, the next time you are out on your bike or if you are on a

> > wind trainer at home try the following.

> >

> > Detach the left foot from its peddle while coasting. Push down with the

> > right foot from 12:00 to 6:00-(180 deg). What happens? The right foot

> > remains at 6:00 and the bike continues to travel forward (or in the case

> of

> > a bike on a wind trainer) the rear wheel continues to spin.

> >

> > There is no flywheel effect. For the right leg to return back to the

> > original 12:00 position to start the next cycle one of two things has to

> > occur.

> >

> > 1) you put your left foot back on the left peddle and push own and in

> this

> > manner you push your right foot and leg back up or

> >

> > 2) You actively engage other muscles in your right leg to pull back and

> up

> > your foot (as in trying to scrape mud off your shoe).

> > In #1 your left leg has to do more work with some of the work being

> > dedicated to lifting the right leg and the rest to propelling the bike

> > forward.

> > In #2 the right leg is working to lift the right peddle thus allowing

> more

> > of the force from the left leg to be dedicated to propelling the bike

> > forward. In this manner the right leg is contributing more than 180deg to

> > the full cycle. The act of pulling through and lifting is called " off

> > loading " .

> >

> > In experienced cyclists this may be as much as 270deg under certain

> > circumstances. It takes a lot of concentration and dedication to learn

> this

> > technique. It does not come naturally.

> > If this is done correctly there is minimal if any slowing of the cycle at

> > any point. This is called peddling in circles. The beginner tends to

> stomp

> > on the peddles (peddling in squares). As a result there is a dead spot in

> > the cycle.

> >

> > In riding uphill it is not only important to shift to lower gears to keep

> > the cadence high for as long as possible but also to shift your weight

> > further back on the saddle, to aid in the pulling back on the peddle.

> Done

> > correctly you will feel your hamstrings begin to burn.

> > What we have lost sight of in this discussion is why is peddling in the

> > 85-95 rpm more efficient energy wise for the endurance cyclists. I

> alluded

> > to that in my previous posts. The mistake often made is to assume that to

> > peddle faster you need to engage TypII (a/b)fibers.

> > The endurance cyclists tries to use Type II fibers sparingly and

> > judiciously throughout the race.

> > Ralph Giarnella MD

> > Southington Ct USA

> >

> > >

> > >

>

>