Originally Posted by Mark Rippetoe
Howdy sir,
Concerning a definition of volume, the only real definition that makes sense to me is the total number of repetitions. If you tie the definition of volume to intensity (% 1RM) or any other variable, how could you ever establish the effect of "volume" against other variables (e.g. intensity and frequency)?
My point in the illustration above was speculation that it wasn't the high reps and the metabolic stuff happening as a result of the high reps responsible for "high rep sets" being more conducive to growth. There's empirical evidence (including the link I sent, and the unpublished study Lyle references) that this is not the case. What appears to matter most, I suppose, is total tonnage - the combination of intensity and volume. How heavy you're lifting, and how many total times you lift it, all else constant. Thus, if you match volume (total reps) in any comparison, a higher intensity will "win" almost irregardless of context (training age of the subjects in question etc), imho.
Regarding sarcoplasmic vs. myofibrillar hypertrophy, I never said that there was no difference between the two per se, but rather that you couldn't separate the two in a meaningful way, and what I had in mind with that comment was the ability to isolate one form of hypertrophy from the other in terms of changes one could make to their training.
Basically, it is my belief that that muscle fibers keep a regulated ratio of protein to sarcoplasmic content, so separating one from the other into discrete categories doesn't really work. Both happen, certainly, so both forms "exist," but I am aware of no evidence to suggest one could ever really happen to the exclusion of the other. In fact, the only place I've seen this suggested (that the two can be meaningfully separated) is Russian literature (e.g. Supertraining), and then some American authors seemed to adopt the idea from them. But I don't believe there was ever a good empirical basis for this belief.
Does fatigue affect the nature of the stimulus, i.e. does specificity still hold? Of course, but first and foremost, changing the nature of the metabolic stimulus will change the fatigue characteristics of that muscle. I.e. you will see adaptations sponsoring an increased efficiency in whatever energy pathway you happen to be using.
However, muscle hypertrophy is, imho, a mechanical phenomenon, a very specific response to strain that results in an increase in protein content of the contractile machinery of muscle tissue. I see the metabolic stuff as secondary to this. Not unrelated, but that the primary stimulus is NOT metabolic in nature, but mechanical. There's actually a really, really good discussion of this in Dan Moore's Max-Stim e-book, which I'll direct you to, if you're interested:
http://www.hypertrophy-research.com/...timulation.pdf
Now, how you train, i.e. higher reps, can absolutely affect the "look" of the muscle, but I would argue that most of this is transient - glycogen/fluid retention. I would go so far to say that, in (lifetime) natural trainees, you would be hard pressed to tell a "lean powerlifter" apart from a bodybuilder. I think a lot of what we identify as the "look" of bodybuilders has a lot more to do with their drugs of choice than their training methods.
Of course, this is all just my opinion, so it can be taken with an enormous grain of salt. But since you asked, I figured I'd explain my reasoning.
