Re: Study: Effects of power training on bone mineral density

[Guest guest]

Did the ST lead to increased injury or pain?

Brett

Draper, UT

>

> Members may find the following to be of interest:

>

> Differential effects of strength versus power training on bone

> mineral density in postmenopausal women: a 2-year longitudinal study

> Simon von Stengel1, Wolfgang Kemmler1, Willi A Kalender1, Klaus

> Engelke1, Dirk Lauber2

>

> British Journal of Sports Medicine 2007;41:649-655

>

> Objectives: To investigate the effect of two different schemes of

> loading in resistance training on bone mineral density (BMD) and pain

> in pretrained postmenopausal women.

>

> Methods: 53 pretrained women (mean (SD) age 58.2 (3.7) years) who

> carried out a mixed resistance and gymnastics programme were randomly

> assigned to a strength training (ST) or power training (PT) group.

> The difference between the two groups was the movement velocity

> during the resistance training (ST, 4 s (concentric)/4 s (eccentric);

> PT, explosive/4 s). Otherwise both groups carried out periodised

> progressive resistance training (10–12 exercises, 2–4 sets, 4–12

> repetitions at 70–92.5% of the one-repetition maximum (2/week) for 2

> years. Mechanical loading was determined with a force measuring plate

> during the leg press exercise. At baseline and after 2 years, BMD was

> measured at different sites with dual x-ray absorptiometry. Pain was

> assessed by questionnaire.

>

> Results: Loading magnitude, loading/unloading rate, loading amplitude

> and loading frequency differed significantly (p<0.001) between the

> two groups. After 2 years, significant between-group differences were

> detected for BMD (PT, –0.3%; ST, –2.4%; p<0.05) and bone area (PT,

> 0.4%; ST, –0.9%; p<0.05) at the lumbar spine. At the hip, there was a

> non-significant trend in favour of the PT group. Also the incidence

> of pain indicators at the lumbar spine was more favourable in the PT

> group.

>

> Conclusion: The results show that PT may be superior for maintaining

> BMD in postmenopausal women. Furthermore, PT was safe as it did not

> lead to increased injury or pain.

>

> ===============

> Carruthers

> Wakefield, UK

>

[Guest guest]

The results support the contention that time under tension protocols are not as

effective as accelerating the weight as explosively as possible. They reported

some really big differences in the rate of force development and some lesser

ones in peak force. The results aren't really surprising but I wonder how much

of a difference would show up in an athletic population over a two year period.

increased acceleration/force=increased training load=increased training

effect.

TUT protocols=non explosive trainees

The program design is pretty interesting. They used really long loading

periods and really long unloading periods. They did not specify the basis of

using such long " mesocycles. " Here is a direct quote from the article:

" A progressive, periodised design was used, which was characterised by 12-week

periods of high-intensity training (70–92.5% of the one-repetition maximum

(1RM)) interspersed with 4–5 weeks of lower training intensity (50% of 1RM)

ensuring enough time for adaptation and regeneration. "

cheers

Matt Barr

London, Ontario, Canada

============================

carruthersjam wrote:

Members may find the following to be of interest:

Differential effects of strength versus power training on bone

mineral density in postmenopausal women: a 2-year longitudinal study

Simon von Stengel1, Wolfgang Kemmler1, Willi A Kalender1, Klaus

Engelke1, Dirk Lauber2

British Journal of Sports Medicine 2007;41:649-655

Objectives: To investigate the effect of two different schemes of

loading in resistance training on bone mineral density (BMD) and pain

in pretrained postmenopausal women.

Methods: 53 pretrained women (mean (SD) age 58.2 (3.7) years) who

carried out a mixed resistance and gymnastics programme were randomly

assigned to a strength training (ST) or power training (PT) group.

The difference between the two groups was the movement velocity

during the resistance training (ST, 4 s (concentric)/4 s (eccentric);

PT, explosive/4 s). Otherwise both groups carried out periodised

progressive resistance training (10–12 exercises, 2–4 sets, 4–12

repetitions at 70–92.5% of the one-repetition maximum (2/week) for 2

years. Mechanical loading was determined with a force measuring plate

during the leg press exercise. At baseline and after 2 years, BMD was

measured at different sites with dual x-ray absorptiometry. Pain was

assessed by questionnaire.

Results: Loading magnitude, loading/unloading rate, loading amplitude

and loading frequency differed significantly (p<0.001) between the

two groups. After 2 years, significant between-group differences were

detected for BMD (PT, –0.3%; ST, –2.4%; p<0.05) and bone area (PT,

0.4%; ST, –0.9%; p<0.05) at the lumbar spine. At the hip, there was a

non-significant trend in favour of the PT group. Also the incidence

of pain indicators at the lumbar spine was more favourable in the PT

group.

Conclusion: The results show that PT may be superior for maintaining

BMD in postmenopausal women. Furthermore, PT was safe as it did not

lead to increased injury or pain.

===============

[Guest guest]

Thanks Matt,

I find this very interesting but I don't feel I have a good understanding what

is actually happening here.

It is simply that accelerating the bar gives better bone density? If it is, I

think I could have worked that out on my own.

It is off topic but what about strength and power development? I have always

read you need TUT. I think it would be interesting to know what other effects

this form of training had. I am interested in the idea of training over 55's

with PL by the way.

It is nice to read the low injury rate as well.

Sharah

Sydney Australia

Re: Study: Effects of power training on bone mineral

density

The results support the contention that time under tension protocols are not as

effective as accelerating the weight as explosively as possible. They reported

some really big differences in the rate of force development and some lesser

ones in peak force. The results aren't really surprising but I wonder how much

of a difference would show up in an athletic population over a two year period.

increased acceleration/ force=increased training load=increased training effect.

TUT protocols=non explosive trainees

The program design is pretty interesting. They used really long loading periods

and really long unloading periods. They did not specify the basis of using such

long " mesocycles. " Here is a direct quote from the article:

" A progressive, periodised design was used, which was characterised by 12-week

periods of high-intensity training (70–92.5% of the one-repetition maximum

(1RM)) interspersed with 4–5 weeks of lower training intensity (50% of 1RM)

ensuring enough time for adaptation and regeneration. "

cheers

Matt Barr

London, Ontario, Canada

============ ========= =======

carruthersjam <Carruthersjam@ aol.com> wrote:

Members may find the following to be of interest:

Differential effects of strength versus power training on bone

mineral density in postmenopausal women: a 2-year longitudinal study

Simon von Stengel1, Wolfgang Kemmler1, Willi A Kalender1, Klaus

Engelke1, Dirk Lauber2

British Journal of Sports Medicine 2007;41:649- 655

Objectives: To investigate the effect of two different schemes of

loading in resistance training on bone mineral density (BMD) and pain

in pretrained postmenopausal women.

Methods: 53 pretrained women (mean (SD) age 58.2 (3.7) years) who

carried out a mixed resistance and gymnastics programme were randomly

assigned to a strength training (ST) or power training (PT) group.

The difference between the two groups was the movement velocity

during the resistance training (ST, 4 s (concentric) /4 s (eccentric);

PT, explosive/4 s). Otherwise both groups carried out periodised

progressive resistance training (10–12 exercises, 2–4 sets, 4–12

repetitions at 70–92.5% of the one-repetition maximum (2/week) for 2

years. Mechanical loading was determined with a force measuring plate

during the leg press exercise. At baseline and after 2 years, BMD was

measured at different sites with dual x-ray absorptiometry. Pain was

assessed by questionnaire.

Results: Loading magnitude, loading/unloading rate, loading amplitude

and loading frequency differed significantly (p<0.001) between the

two groups. After 2 years, significant between-group differences were

detected for BMD (PT, –0.3%; ST, –2.4%; p<0.05) and bone area (PT,

0.4%; ST, –0.9%; p<0.05) at the lumbar spine. At the hip, there was a

non-significant trend in favour of the PT group. Also the incidence

of pain indicators at the lumbar spine was more favourable in the PT

group.

Conclusion: The results show that PT may be superior for maintaining

BMD in postmenopausal women. Furthermore, PT was safe as it did not

lead to increased injury or pain.

============ ===

[Guest guest]

" .....gives results for pain frequency and intensity in the lower back and big

joints (hip, knee, shoulder). These regions in particular were loaded during our

resistance training regimen. In the ST group, a significant increase in pain

intensity at the lumbar spine was observed, whereas a slight non-significant

decrease was found in the PT group. This resulted in a significant between-group

difference for pain intensity in the lumbar spine. At the spine, similar but

insignificant results were found for pain frequency. For the big joints, a

significant decrease in pain frequency was even observed in the PT group. No

significant within-group or between-group differences could be detected for pain

in the small joints or the thoracic or cervical spine. "

Matt Barr

London, Ontario, Canada

======================

Brett wrote:

Did the ST lead to increased injury or pain?

Brett

Draper, UT

>

> Members may find the following to be of interest:

>

> Differential effects of strength versus power training on bone

> mineral density in postmenopausal women: a 2-year longitudinal study

> Simon von Stengel1, Wolfgang Kemmler1, Willi A Kalender1, Klaus

> Engelke1, Dirk Lauber2

>

> British Journal of Sports Medicine 2007;41:649-655

>

> Objectives: To investigate the effect of two different schemes of

> loading in resistance training on bone mineral density (BMD) and pain

> in pretrained postmenopausal women.

>

> Methods: 53 pretrained women (mean (SD) age 58.2 (3.7) years) who

> carried out a mixed resistance and gymnastics programme were randomly

> assigned to a strength training (ST) or power training (PT) group.

> The difference between the two groups was the movement velocity

> during the resistance training (ST, 4 s (concentric)/4 s (eccentric);

> PT, explosive/4 s). Otherwise both groups carried out periodised

> progressive resistance training (10–12 exercises, 2–4 sets, 4–12

> repetitions at 70–92.5% of the one-repetition maximum (2/week) for 2

> years. Mechanical loading was determined with a force measuring plate

> during the leg press exercise. At baseline and after 2 years, BMD was

> measured at different sites with dual x-ray absorptiometry. Pain was

> assessed by questionnaire.

>

> Results: Loading magnitude, loading/unloading rate, loading amplitude

> and loading frequency differed significantly (p<0.001) between the

> two groups. After 2 years, significant between-group differences were

> detected for BMD (PT, –0.3%; ST, –2.4%; p<0.05) and bone area (PT,

> 0.4%; ST, –0.9%; p<0.05) at the lumbar spine. At the hip, there was a

> non-significant trend in favour of the PT group. Also the incidence

> of pain indicators at the lumbar spine was more favourable in the PT

> group.

>

> Conclusion: The results show that PT may be superior for maintaining

> BMD in postmenopausal women. Furthermore, PT was safe as it did not

> lead to increased injury or pain.

>

> ===============

> Carruthers

> Wakefield, UK

>

[Guest guest]

,

The concept behind TUT ignores the idea of force and acceleration. The idea

is that if you are, for example, squatting 5 reps of 100kg it is better to do it

slowly. If you did the 5 reps with a 4s concentric contractions you would have

20s of total TUT. If you did the same explosively you would have less than 5s

TUT.

The problem with this is that the peak force and rate of force development are

always much lower in the in TUT protocol. You may have spent more time under

tension but it was at much lower force (and muscle tension). I have done sets

with TUT and explosive protocols on a force plate and there are some big

differences in peak force and rate of force development.

The more tension that muscles place on the bone the greater the stimuli for

the bone to increase it density. The muscles develop more tension maximally

accelerating the weight than they would following a 4s up protocol. The authors

stated that peak tension and loading rate are both important for increasing bone

density. Moving the weight quickly will lead to some increase both of those

factors.

From a functional perspective it also makes sense for older people to lift

things quickly. Getting out of a chair or picking up a heavy object and putting

on a high shelf are done quickly.

cheers

Matt Barr

London, Ontario, Canada

Sharah wrote:

Thanks Matt,

I find this very interesting but I don't feel I have a good understanding what

is actually happening here.

It is simply that accelerating the bar gives better bone density? If it is, I

think I could have worked that out on my own.

It is off topic but what about strength and power development? I have always

read you need TUT. I think it would be interesting to know what other effects

this form of training had. I am interested in the idea of training over 55's

with PL by the way.

It is nice to read the low injury rate as well.

Sharah

Sydney Australia

Re: Study: Effects of power training on bone mineral

density

The results support the contention that time under tension protocols are not as

effective as accelerating the weight as explosively as possible. They reported

some really big differences in the rate of force development and some lesser

ones in peak force. The results aren't really surprising but I wonder how much

of a difference would show up in an athletic population over a two year period.

increased acceleration/ force=increased training load=increased training effect.

TUT protocols=non explosive trainees

The program design is pretty interesting. They used really long loading periods

and really long unloading periods. They did not specify the basis of using such

long " mesocycles. " Here is a direct quote from the article:

" A progressive, periodised design was used, which was characterised by 12-week

periods of high-intensity training (70–92.5% of the one-repetition maximum

(1RM)) interspersed with 4–5 weeks of lower training intensity (50% of 1RM)

ensuring enough time for adaptation and regeneration. "

cheers

Matt Barr

London, Ontario, Canada

============ ========= =======

carruthersjam <Carruthersjam@ aol.com> wrote:

Members may find the following to be of interest:

Differential effects of strength versus power training on bone

mineral density in postmenopausal women: a 2-year longitudinal study

Simon von Stengel1, Wolfgang Kemmler1, Willi A Kalender1, Klaus

Engelke1, Dirk Lauber2

British Journal of Sports Medicine 2007;41:649- 655

Objectives: To investigate the effect of two different schemes of

loading in resistance training on bone mineral density (BMD) and pain

in pretrained postmenopausal women.

Methods: 53 pretrained women (mean (SD) age 58.2 (3.7) years) who

carried out a mixed resistance and gymnastics programme were randomly

assigned to a strength training (ST) or power training (PT) group.

The difference between the two groups was the movement velocity

during the resistance training (ST, 4 s (concentric) /4 s (eccentric);

PT, explosive/4 s). Otherwise both groups carried out periodised

progressive resistance training (10–12 exercises, 2–4 sets, 4–12

repetitions at 70–92.5% of the one-repetition maximum (2/week) for 2

years. Mechanical loading was determined with a force measuring plate

during the leg press exercise. At baseline and after 2 years, BMD was

measured at different sites with dual x-ray absorptiometry. Pain was

assessed by questionnaire.

Results: Loading magnitude, loading/unloading rate, loading amplitude

and loading frequency differed significantly (p<0.001) between the

two groups. After 2 years, significant between-group differences were

detected for BMD (PT, –0.3%; ST, –2.4%; p<0.05) and bone area (PT,

0.4%; ST, –0.9%; p<0.05) at the lumbar spine. At the hip, there was a

non-significant trend in favour of the PT group. Also the incidence

of pain indicators at the lumbar spine was more favourable in the PT

group.

Conclusion: The results show that PT may be superior for maintaining

BMD in postmenopausal women. Furthermore, PT was safe as it did not

lead to increased injury or pain.

============ ===

[Guest guest]

Hi Matt,

I am very interested in your test results.

I have performed force plate tests with different training tools, such as squat

with extra weights, jumps with weight vest and Vertimax, and even on a vibrating

plate, and I've had some very interesting results.

We compared the chair rising test with jump test and found a maximal force that

was almost equal. The highest Force and RFD can be found during the landing

after a jump. Some training tools offer a high RFD without high peak forces.

As you mentioned, peak force and/or RFD seem to be decisive in the development

of bone, and they form the basis of the research going on at ESA on training

programs for astronauts (Bed rest study;

http://www.esa.int/esaHS/SEMHUJ2A6BD_research_0.html).

I think the use of force plates could help a lot in the discussion of different

training programs.

Huizing

The Netherlands

Re: Study: Effects of power training on bone mineral

density

,

The concept behind TUT ignores the idea of force and acceleration. The idea is

that if you are, for example, squatting 5 reps of 100kg it is better to do it

slowly. If you did the 5 reps with a 4s concentric contractions you would have

20s of total TUT. If you did the same explosively you would have less than 5s

TUT.

The problem with this is that the peak force and rate of force development are

always much lower in the in TUT protocol. You may have spent more time under

tension but it was at much lower force (and muscle tension). I have done sets

with TUT and explosive protocols on a force plate and there are some big

differences in peak force and rate of force development.

The more tension that muscles place on the bone the greater the stimuli for the

bone to increase it density. The muscles develop more tension maximally

accelerating the weight than they would following a 4s up protocol. The authors

stated that peak tension and loading rate are both important for increasing bone

density. Moving the weight quickly will lead to some increase both of those

factors.

From a functional perspective it also makes sense for older people to lift

things quickly. Getting out of a chair or picking up a heavy object and putting

on a high shelf are done quickly.

cheers

Matt Barr

London, Ontario, Canada

=========================================

[Guest guest]

This is interesting stuff. It is important to note the the peak force is

highest during rapid movements such as jumping, landing from a jump or pressing

a (heavy) weight rapidly - but that is only at one point in the range of motion

and the average force may be lower across the full range of the motion. For

example if you accelerate the weight during a bench press as rapidly as you can

the force will peak about 1/2 the way up then the force decreases as the weight

is already moving fast and it takes less force to keep in moving up. On the

other hand if you lift a heavy weight in a controlled fashion the force will be

a lot more constant through the whole range. Also, you can create a higher peak

force with a moderate weight compared to a very heavy weight. This is because

with a moderate weight you can accelerate it a lot faster and the increased

speed more than makes up for the reduced mass of the weight (F=M * A).

I am interested to find out if the increase in bone density from the high force

training is along the entire length of the bone, or if it is selective in the

area that sees the force spike from the high-force training.

Sorry, but I am not convinced that we should go out and tell old people with bad

joints to train ballistically and do plyometrics in order to increase their bone

densities - while maybe destroying their joints.

Ed White

Sandwich, MA USA

Huizing wrote:

Hi Matt,

I am very interested in your test results.

I have performed force plate tests with different training tools, such as squat

with extra weights, jumps with weight vest and Vertimax, and even on a vibrating

plate, and I've had some very interesting results.

We compared the chair rising test with jump test and found a maximal force that

was almost equal. The highest Force and RFD can be found during the landing

after a jump. Some training tools offer a high RFD without high peak forces.

As you mentioned, peak force and/or RFD seem to be decisive in the development

of bone, and they form the basis of the research going on at ESA on training

programs for astronauts (Bed rest study;

http://www.esa.int/esaHS/SEMHUJ2A6BD_research_0.html).

I think the use of force plates could help a lot in the discussion of different

training programs.

Huizing

The Netherlands

Re: Study: Effects of power training on bone mineral

density

,

The concept behind TUT ignores the idea of force and acceleration. The idea is

that if you are, for example, squatting 5 reps of 100kg it is better to do it

slowly. If you did the 5 reps with a 4s concentric contractions you would have

20s of total TUT. If you did the same explosively you would have less than 5s

TUT.

The problem with this is that the peak force and rate of force development are

always much lower in the in TUT protocol. You may have spent more time under

tension but it was at much lower force (and muscle tension). I have done sets

with TUT and explosive protocols on a force plate and there are some big

differences in peak force and rate of force development.

The more tension that muscles place on the bone the greater the stimuli for the

bone to increase it density. The muscles develop more tension maximally

accelerating the weight than they would following a 4s up protocol. The authors

stated that peak tension and loading rate are both important for increasing bone

density. Moving the weight quickly will lead to some increase both of those

factors.

From a functional perspective it also makes sense for older people to lift

things quickly. Getting out of a chair or picking up a heavy object and putting

on a high shelf are done quickly.

cheers

Matt Barr

London, Ontario, Canada

=========================================

[Guest guest]

Hi Ed

Although I understand your concerns here are some observations from what I

saw in the study abstract.

It was conducted over a two year period using a progressive development of

the training protocols by pretrained woman average age 58 (not that

old). The two year protocol would have allowed the particiapnts bodies time

to adapt to the training protocols. The weights used were around 70 to 92 %

of 1RM. In Supertraining it is mentioned that optimal power development is

generated at about 70% of 1RM as a good balance point between speed and

weight if I recal correctly. Both groups used the same weights just the

nature of the concentric portion of the lift differed.

The point is not that we should get some old people out of their weel chairs

and doing drop jumps from 1meter, but that in this group the the power

training helped more than the time under tension group. This has

implications for how to develop longer term training goals to improve bone

density and reduce perceived joint pain in older trainees.

Since the body adapts to stress by strengthening itself to handle that

stress a carefully applied programme tending towards the parameters of the

power study could be helpful. Have you evidence that a programme like this

power training is bad for the joints? This study didn't show that up it

showed the opposite. I think the key here is carefully applied and

progressive.

As a slight off topic comment if you have a look at the recent world masters

weightlifting championships you will see 80+ year olds snatching and clean

and jerking up to 60kg. I'm sure these people are exceptions in the general

population and have been at weightlifting for most of their lives, but then

that points towards power training certainly helping the quality of life for

those athletes.

Your thoughts?

Best Regards

Nick Tatalias

Johanesburg

South Africa

>

> This is interesting stuff. It is important to note the the peak force is

> highest during rapid movements such as jumping, landing from a jump or

> pressing a (heavy) weight rapidly - but that is only at one point in the

> range of motion and the average force may be lower across the full range of

> the motion. For example if you accelerate the weight during a bench press as

> rapidly as you can the force will peak about 1/2 the way up then the force

> decreases as the weight is already moving fast and it takes less force to

> keep in moving up. On the other hand if you lift a heavy weight in a

> controlled fashion the force will be a lot more constant through the whole

> range. Also, you can create a higher peak force with a moderate weight

> compared to a very heavy weight. This is because with a moderate weight you

> can accelerate it a lot faster and the increased speed more than makes up

> for the reduced mass of the weight (F=M * A).

>

> I am interested to find out if the increase in bone density from the high

> force training is along the entire length of the bone, or if it is selective

> in the area that sees the force spike from the high-force training.

>

> Sorry, but I am not convinced that we should go out and tell old people

> with bad joints to train ballistically and do plyometrics in order to

> increase their bone densities - while maybe destroying their joints.

>

> Ed White

> Sandwich, MA USA

>

> Huizing <martinhuizing1@... <martinhuizing1%40yahoo.com>>

> wrote: Hi Matt,

>

> I am very interested in your test results.

>

> I have performed force plate tests with different training tools, such as

> squat with extra weights, jumps with weight vest and Vertimax, and even on a

> vibrating plate, and I've had some very interesting results.

> We compared the chair rising test with jump test and found a maximal force

> that was almost equal. The highest Force and RFD can be found during the

> landing after a jump. Some training tools offer a high RFD without high peak

> forces.

>

> As you mentioned, peak force and/or RFD seem to be decisive in the

> development of bone, and they form the basis of the research going on at ESA

> on training programs for astronauts (Bed rest study;

> http://www.esa.int/esaHS/SEMHUJ2A6BD_research_0.html).

>

> I think the use of force plates could help a lot in the discussion of

> different training programs.

>

> Huizing

> The Netherlands

>

> Re: Study: Effects of power training on bone

> mineral density

>

> ,

>

> The concept behind TUT ignores the idea of force and acceleration. The

> idea is that if you are, for example, squatting 5 reps of 100kg it is better

> to do it slowly. If you did the 5 reps with a 4s concentric contractions you

> would have 20s of total TUT. If you did the same explosively you would have

> less than 5s TUT.

>

> The problem with this is that the peak force and rate of force development

> are always much lower in the in TUT protocol. You may have spent more time

> under tension but it was at much lower force (and muscle tension). I have

> done sets with TUT and explosive protocols on a force plate and there are

> some big differences in peak force and rate of force development.

>

> The more tension that muscles place on the bone the greater the stimuli

> for the bone to increase it density. The muscles develop more tension

> maximally accelerating the weight than they would following a 4s up

> protocol. The authors stated that peak tension and loading rate are both

> important for increasing bone density. Moving the weight quickly will lead

> to some increase both of those factors.

>

> From a functional perspective it also makes sense for older people to lift

> things quickly. Getting out of a chair or picking up a heavy object and

> putting on a high shelf are done quickly.

>

> cheers

> Matt Barr

> London, Ontario, Canada

> =========================================

>

>

>

>

>