Great, great work on this whole meta-analysis series.
Kudos to you – heavy science articles like those are reason why I read and share this site with others.
I’m just wondering – most of those researches are not on people that are experienced in weightlifting/bodybuilding?
So maybe this “dilution” of “best range for hypertrophy” is coming from high level of “nub gains”, when new people will grow their muscles rapidly regardless of exercise, rep range, proper movement, isolation, TUT, etc…
And maybe in people with 2+ years of experience, when hypertrophy slows down significantly, all those things get more and more relatively important?
Finally, and this is likely the biggest and most important question, but what exactly stimulates hypertrophy? There are hypotheses out there, some of which are supported by evidence, but in my opinion, it is still inconclusive. (20) Tension on muscles themselves might be enough to stimulate hypertrophy, but when you get tension, you also get ischemia and increased metabolite build-up. The pump you get from lifting weights might contribute, but heavy weight/low rep sets tend not to elicit much of a pump, and hypertrophy has been shown to be the same as for higher rep sets. Metabolic byproduct concentration might be the main stimulator, but there isn’t much evidence examining the idea yet. At this point, we can only conclusively look at muscle growth on a large scale and say that picking things up and putting them down a lot makes muscles get bigger.