Guest guest Posted December 15, 2003 Report Share Posted December 15, 2003 > " A > >noticeable feature of Jay's programs is that everything is either very > >heavy or very fast- nothing in-between. There really is no repeated effort > >method at all, although perhaps he would use this for an athlete needing to > >get bigger. " > > The following study shows an increase in IIB fiber % with weight training > using high speed eccentrics. If one examines the role of the faster > contracting fibers (IIB,C,X, etc), it would seem one way to maximize their > availability would be to expose the body to both very high forces and very > fast forces at the same time. If the body can get the job done with IIA it > will, but perhaps if exposed to supramaximal forces over a period of time > (as can be done with plyometric training), the only logical adaptation is to > a faster and stronger fiber. I think its important to look at what signals > the training is sending to the nervous and metabolic system. When > performing submaximal eccentric accentuated training, the load is such that > it can be dealt with easily enough, so the metabolic adaptation favors the > more efficient IIA fiber. When performing supramaximal eccentrics or > plyometrics, the load is either more then the body can handle or occurs with > lots of simultaneous force and speed, both which favor a faster and stronger > fiber, the IIB. ***Remember though that MHC expression in a fiber is not necessarily indicative of it's hypertrophic capacities. MHC expression, IIRC, is more related to contraction velocity as opposed to maximal force output (as in, MHC IIa and IIx both have identical force outputs, but IIx is " faster " ). Nothing has been directly done academically to support this (that I'm aware of), but my thoughts on the matter are that the MHC IIx isoform is the " default " state of a given population of high- threshold motor units. The observation that most strength athletes show a predominance of IIa fibers is a result of form following function-- strength training doesn't require IIx fibers, and the IIa state is somehow more beneficial to maximal and/or repeated efforts. On the other hand we have explosive strength/RFD and reactive ability, as in the study you listed (they used isokinetic equipment if that's the same study I'm thinking of, but for the sake of this thought experiment I'll consider it valid for movements without fixed velocity), showing that IIx expression becomes more dominant with exposure to faster movements. It also seems to me that weightlifters and sprinters, groups that both regularly engage in movements with high RFD, showed similar characteristics. Just extrapolating from those facts, it seems that individuals involved in pure strength training via maximal and repeated efforts show a conversion from the " default " IIx expression of higher threshold MU's to a more efficient IIa. Those involved in training that involves training for a high RFD and for reversal strength show a greater dominance of IIx fibers. The IIx " overshoot " phenomenon observed with periods of detraining could simply be those fibers returning to their " default " states. The question is, does the MHC conversion provide a physiological reason for the observed loss of speed-strength characteristics after periods of heavy strength training? I'd be willing to bet it is at least related. Interestingly enough, this idea fits in nicely with Verkhoshansky's concentration of loading periodization model, where speed-strength characteristics are enhanced sharply after periods of high-volume strength trainig. Now, as I said above this is all hypothesizing on my part so far as I'm aware, but it is consistent with the literature. If it is the case, it provides even more evidence for the concept of training for goals, not for fibers, but also for structuring periods of strength training with periods of speed-strength training. If one is concerned with simple hypertrophy (yes, I finally got to the original question), then it's really hard to go wrong assuming the proper intensity, volume, density, and quality of eccentric action is present. So yeah, maximal and ballistic-type movements could potentially be very useful for hypertrophy. man Birmingham, AL www.wannabebig.com www.fortifiediron.com Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 15, 2003 Report Share Posted December 15, 2003 > " A > >noticeable feature of Jay's programs is that everything is either very > >heavy or very fast- nothing in-between. There really is no repeated effort > >method at all, although perhaps he would use this for an athlete needing to > >get bigger. " > > The following study shows an increase in IIB fiber % with weight training > using high speed eccentrics. If one examines the role of the faster > contracting fibers (IIB,C,X, etc), it would seem one way to maximize their > availability would be to expose the body to both very high forces and very > fast forces at the same time. If the body can get the job done with IIA it > will, but perhaps if exposed to supramaximal forces over a period of time > (as can be done with plyometric training), the only logical adaptation is to > a faster and stronger fiber. I think its important to look at what signals > the training is sending to the nervous and metabolic system. When > performing submaximal eccentric accentuated training, the load is such that > it can be dealt with easily enough, so the metabolic adaptation favors the > more efficient IIA fiber. When performing supramaximal eccentrics or > plyometrics, the load is either more then the body can handle or occurs with > lots of simultaneous force and speed, both which favor a faster and stronger > fiber, the IIB. ***Remember though that MHC expression in a fiber is not necessarily indicative of it's hypertrophic capacities. MHC expression, IIRC, is more related to contraction velocity as opposed to maximal force output (as in, MHC IIa and IIx both have identical force outputs, but IIx is " faster " ). Nothing has been directly done academically to support this (that I'm aware of), but my thoughts on the matter are that the MHC IIx isoform is the " default " state of a given population of high- threshold motor units. The observation that most strength athletes show a predominance of IIa fibers is a result of form following function-- strength training doesn't require IIx fibers, and the IIa state is somehow more beneficial to maximal and/or repeated efforts. On the other hand we have explosive strength/RFD and reactive ability, as in the study you listed (they used isokinetic equipment if that's the same study I'm thinking of, but for the sake of this thought experiment I'll consider it valid for movements without fixed velocity), showing that IIx expression becomes more dominant with exposure to faster movements. It also seems to me that weightlifters and sprinters, groups that both regularly engage in movements with high RFD, showed similar characteristics. Just extrapolating from those facts, it seems that individuals involved in pure strength training via maximal and repeated efforts show a conversion from the " default " IIx expression of higher threshold MU's to a more efficient IIa. Those involved in training that involves training for a high RFD and for reversal strength show a greater dominance of IIx fibers. The IIx " overshoot " phenomenon observed with periods of detraining could simply be those fibers returning to their " default " states. The question is, does the MHC conversion provide a physiological reason for the observed loss of speed-strength characteristics after periods of heavy strength training? I'd be willing to bet it is at least related. Interestingly enough, this idea fits in nicely with Verkhoshansky's concentration of loading periodization model, where speed-strength characteristics are enhanced sharply after periods of high-volume strength trainig. Now, as I said above this is all hypothesizing on my part so far as I'm aware, but it is consistent with the literature. If it is the case, it provides even more evidence for the concept of training for goals, not for fibers, but also for structuring periods of strength training with periods of speed-strength training. If one is concerned with simple hypertrophy (yes, I finally got to the original question), then it's really hard to go wrong assuming the proper intensity, volume, density, and quality of eccentric action is present. So yeah, maximal and ballistic-type movements could potentially be very useful for hypertrophy. man Birmingham, AL www.wannabebig.com www.fortifiediron.com Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 22, 2003 Report Share Posted December 22, 2003 ***Remember though that MHC expression in a fiber is not necessarily indicative of it's hypertrophic capacities. MHC expression, IIRC, is more related to contraction velocity as opposed to maximal force output (as in, MHC IIa and IIx both have identical force outputs, but IIx is " faster " ). The original statement was that Schroeder used contraction speeds that were very fast and loads that were very high and nothing in between and I was trying to give some reasons why. Speed is obviously always going to be important for any athlete but for example, if one needs hypertrophy, there are several different ways of training for that. One could train like a bodybuilder with lots of pump sets and put on plenty of muscle, but what is that going to do to contraction speeds? There are different means of arriving at the same goal and I think what Schroeder does is keep both the short term and long term goals, signals, and adaptations in mind. Baggett on,AR USA _________________________________________________________________ Worried about inbox overload? Get MSN Extra Storage now! http://join.msn.com/?PAGE=features/es Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 22, 2003 Report Share Posted December 22, 2003 ***Remember though that MHC expression in a fiber is not necessarily indicative of it's hypertrophic capacities. MHC expression, IIRC, is more related to contraction velocity as opposed to maximal force output (as in, MHC IIa and IIx both have identical force outputs, but IIx is " faster " ). The original statement was that Schroeder used contraction speeds that were very fast and loads that were very high and nothing in between and I was trying to give some reasons why. Speed is obviously always going to be important for any athlete but for example, if one needs hypertrophy, there are several different ways of training for that. One could train like a bodybuilder with lots of pump sets and put on plenty of muscle, but what is that going to do to contraction speeds? There are different means of arriving at the same goal and I think what Schroeder does is keep both the short term and long term goals, signals, and adaptations in mind. Baggett on,AR USA _________________________________________________________________ Worried about inbox overload? Get MSN Extra Storage now! http://join.msn.com/?PAGE=features/es Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 22, 2003 Report Share Posted December 22, 2003 > Just extrapolating from those facts, it seems that individuals > involved in pure strength training via maximal and repeated efforts > show a conversion from the " default " IIx expression of higher > threshold MU's to a more efficient IIa. Those involved in training > that involves training for a high RFD and for reversal strength show > a greater dominance of IIx fibers. IIB/X fibers are the so-called " couch potato " fibers. The overwhelming majority of the research is showing a decrease in the expression of MHC IIb/x protein and an increase in MHC IIa proteins. In strength and power sports, this occurs regardless if it is a more " strength-oriented " or " power-oriented " - see Fry et al. in the last two issues of Journal of Strength and Conditioning Research - one article on biopsies in powerlifters, the other in weightlifters. In general, a shift of MHC IIb/x to MHC IIa occurs within two weeks of initition of training in untrained individuals (Staron et al. JAP 1994?) > The IIx " overshoot " phenomenon observed with periods of detraining > could simply be those fibers returning to their " default " states. > The question is, does the MHC conversion provide a physiological > reason for the observed loss of speed-strength characteristics after > periods of heavy strength training? Unlikely. Research we presented (while I was at The University of Memphis) at the 2002 NSCA conference indicated that decreases in speed and power related variables during high relative intensity overtraining were unrelated to changes in MHC expression. The abstracts are available online for NSCA members (Fry et al. and Schilling et al.). Also see Chiu and in the latest Strength and Conditioning Journal (yeah, I'm plugging my own article . Myosin heavy chain expression appears to become fairly stable following a prolonged period of training, and is thus a general fitness characteristic. Changes in speed and power related variables tend to occur as an acute response or short-term adaptation making these a function of fitness and/or fatigue after-effects. -- Loren Chiu, M.S., C.S.C.S. Department of Biokinesiology and Physical Therapy University of Southern California LA Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 22, 2003 Report Share Posted December 22, 2003 > Just extrapolating from those facts, it seems that individuals > involved in pure strength training via maximal and repeated efforts > show a conversion from the " default " IIx expression of higher > threshold MU's to a more efficient IIa. Those involved in training > that involves training for a high RFD and for reversal strength show > a greater dominance of IIx fibers. IIB/X fibers are the so-called " couch potato " fibers. The overwhelming majority of the research is showing a decrease in the expression of MHC IIb/x protein and an increase in MHC IIa proteins. In strength and power sports, this occurs regardless if it is a more " strength-oriented " or " power-oriented " - see Fry et al. in the last two issues of Journal of Strength and Conditioning Research - one article on biopsies in powerlifters, the other in weightlifters. In general, a shift of MHC IIb/x to MHC IIa occurs within two weeks of initition of training in untrained individuals (Staron et al. JAP 1994?) > The IIx " overshoot " phenomenon observed with periods of detraining > could simply be those fibers returning to their " default " states. > The question is, does the MHC conversion provide a physiological > reason for the observed loss of speed-strength characteristics after > periods of heavy strength training? Unlikely. Research we presented (while I was at The University of Memphis) at the 2002 NSCA conference indicated that decreases in speed and power related variables during high relative intensity overtraining were unrelated to changes in MHC expression. The abstracts are available online for NSCA members (Fry et al. and Schilling et al.). Also see Chiu and in the latest Strength and Conditioning Journal (yeah, I'm plugging my own article . Myosin heavy chain expression appears to become fairly stable following a prolonged period of training, and is thus a general fitness characteristic. Changes in speed and power related variables tend to occur as an acute response or short-term adaptation making these a function of fitness and/or fatigue after-effects. -- Loren Chiu, M.S., C.S.C.S. Department of Biokinesiology and Physical Therapy University of Southern California LA Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 28, 2003 Report Share Posted December 28, 2003 Also see Chiu and in the latest Strength and Conditioning Journal (yeah, I'm plugging my own article . ***Let me also plug Chiu and " The Fitness-Fatigue Model Revisited: Implications for Planning Short- and Long-Term Training. " It is an excellent piece of work! Kenny Croxdale Rio Rancho, NM Quote Link to comment Share on other sites More sharing options...
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