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Latest Study On Driver Of Hypertrophy

I know there was another thread postulating what the main driver of muscle growth is (and we l know what that thread turned into -lol), but Layne cited the latest study and put these simple slides up breaking down the set up and findings.

(Someone else can find and link the actual study if anyone wants)




He makes a strength results inference - do you know if that was reported in the study?

Soooo…VOLUME is the main driver of hypertrophy…

Sooooo…NOT intensity…


Did they try reducing the volume in any control group? I can’t find the study.

I haven’t had a chance to actually pull up the study myself, but whether you’re a fan or not of Layne, he’s pretty good breaking down studies, and not your typical “I wanna be an online coach”-trying to make every study sound like it supports his personal viewpoints.

When I saw this on my Ig feed earlier I just quickly grabbed the screenshots until I have more time to take a real dive.


Ok Stu, but I am having some real confirmation bias crisis issues here, so don’t leave me hangin’

But if I am not mistaking, this study doesnt compare volume vs intensity or lower volume vs higher volume, just rep ranges when wolume is equal.

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Exactly, which to me, does not lead to a conclusion that volume is a key variable.

And maybe, they all used the same RIR, or dare I say it…intensity. I said it.

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As a training variable, what is intensity?

We know what volume is, percentage of one rep max is easily calculated, but what is intensity?

How would we find that or standardize it in two, or two hundred random strangers?

I’m interested in how group 1 managed to do 7 sets of 4 with 90% of their one rep max twice a week for ten weeks.


I like the concept of RIR, Reps in Reserve, as a measure of intensity, and I recognize that this is not a constant or stable variable. Therefore it is tricky to standardize. I suppose human evolution does not care about hypertrophy studies.

For me, I like the idea of pushing to a last grinding do-or-die last rep once in a while to see what I got. Then dial it back to two RIR, then just one RIR for a while, then back again for another go at a new rep PR.

Yeah, but in sports science, how does one apply intensity as a variable?

How does one quantify intensity for scientific applications?

Lower volume to failure(or beyond) vs higher volume not to failure.All to some set degree.

That kind of study would lead to a somewhat conclusion which is the main driver. Or at least some direction in that sense.

Test regularly during the study for max reps as part of the lifting program, using a lift that allows safe controlled rep PRs, like machine lifts. Define failure as a certain percentage reduction in rep concentric speed. Then dial it back a set number of reps in reserve for the other sessions in the study, until the next programmed rep PR. I think that would work well.

Or maybe, we should just ask a lot of bodybuilders, how they do…

The problem I see with intensity as a descriptor is that it describes a perceptual phenominon, not a physical one.

Level of arousal, psych-up, intensity, sure it fits. But it just doesn’t make much sense as a training variable.

Even Isreatel kinda winced when it was introduced to their discussion, then steered it to RIR, agreeing that even rir is an imperfect but close enough tool for these purposes.


But why?
Failure= absolute fail to do another concentric rep.
Easy to observe, right?
Not to failure routine(in hypothetical study) would be just set to some point short of previously tested failure point.
No squats or DL or other “dangerous” eyercises that are anyway not recommended to execution to failure.

Yes! But their purpose was to have a discussion, not develop data.

I think we’re talking past each other here.

To state it clearly,

There is no comparison of intensity because intensity is an emotional variable, not a physical one.

My version of intense is another person’s lame, is another person’s etc.

These all describe perceptions. Not physical drivers of hypertrophy.


I have to step out of the discussion at this point. Lost track of time. It’s been good though. TTtyl. :+1:

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This would destroy me and probably any lifter that is good at expressing strength. 90% twice a week for 10 weeks? Yikes.

I wouldn’t get through the first workout.

I can’t normally get 4 reps with 90% for one set, let alone for 7 sets. Would be impossible for me to complete. I will need to read the study as this doesn’t seem right.