Welcome back to The Deep Dive. Today we're tackling
something you hear, well, all the time in fitness
circles. This idea that doing too much training
volume for muscle growth, you know, beyond a
certain point, it just becomes junk volume. Right,
the point of diminishing returns or even negative
returns. Exactly. And it often stems from this
assumption that strength gains kind of hit a
ceiling at pretty low volumes, maybe five sets
a week or so. Yeah. And people then extrapolate
that thinking muscle growth must also stall out
right there. But is that really the whole story?
That's what we're digging into today. This really
fascinating and honestly. often debated relationship
between volume, hypertrophy, that's muscle growth,
and, of course, strength gains. Absolutely. We've
pulled together quite a bit of research here.
We're talking meta -analyses, recent studies,
really trying to challenge that common view.
Yeah, maybe find some surprises along the way.
I think we will. The goal here is to cut through
some of the noise, clear up maybe some misconceptions.
And give you, our listeners, a much clearer evidence
-based picture. You know, so you can figure out
what actually makes sense for your training.
Precisely. Help you make informed decisions.
OK, so where do we kick this off? Let's start
with that traditional view you mentioned, the
one that's been so dominant. Sounds good. So
let's lay out that common argument first. You
mentioned those Pelin meta regressions. Big analysis,
right? Combining lots of studies. And initially,
they seem to show strength gains kind of petering
out beyond, what, about five sets per muscle
group per week? That was the initial interpretation.
Yeah, around that mark. which then led people
to think, okay, the real growth, the contractile
stuff, the myofibrillar hypergraphy that makes
you stronger, that must also plateau there. Right.
And any exercise people saw with higher volumes,
that got dismissed. Dismissed as what, like water
weight or something? Pretty much. Things like
temporary muscle swelling or maybe this other
concept, sarcoplasmic hypertrophy growth of the
non -contractile bits, basically not real strength
producing muscle. OK, but you hinted earlier
that maybe this comparison isn't quite right.
Yeah, that's putting it mildly. The direct comparison
between the strength results and the hypertrophy
results in that Pellin paper, it's actually quite
misleading. Misleading? How so? I thought meta
-analyses were supposed to give us the big picture.
If the studies weren't the same, what's the issue?
Well, that is the issue. They weren't based on
the same set of studies. It's a bit of an apples
and oranges problem. OK, explain that. So the
strength analysis had like 66 studies, over 2
,000 people. The hypertrophy one, only 35 studies,
about 1 ,000 people. Right, so fewer studies
for hypertrophy. And crucially, only 21 studies
were actually in both analyses. Ah, okay. So
lots of studies were only in one or the other.
Exactly. And a whole bunch of those studies that
were only in the strength analysis used untrained
subjects. Untrained people. Okay, why does that
matter so much? They get stronger, right? They
get stronger really fast, yeah. But a huge chunk
of that initial strength gain comes from neural
adaptations. Basically, their brain and nerves
just get much better at firing the muscles they
already have. Ah, so it's learning the movement,
becoming more efficient. Not necessarily building
bigger muscles, especially not at low volumes.
Precisely. And when you include all those studies
with massive neural gains in the strength analysis,
but not in the hypertrophy one, it really warps
the picture. It makes it look like strength plateaus
way earlier relative to volume than it might
actually do if you're just looking at muscle
growth itself. OK, that makes sense. It's kind
of muddied the waters by mixing beginners with
experienced lifters. So what happens if we clean
that up? If we look only at studies with training
where they measured both strength and muscle
size. Does the story change? Oh, absolutely.
It changes significantly. When you isolate those
studies, train folks. measuring both things like
maybe squat strength and quant thickness, a very
different pattern. We looked at data points from
five such studies covering nine different strength
measurements. The groups doing higher volume
averaging around, say, 27 sets a week. OK, that's
quite a bit. Yeah, they gained more strength
in seven out of those nine comparisons compared
to the lower volume groups who were doing maybe
19 sets a week. Seven out of nine. That's pretty
consistent. And muscle growth. Even more consistent.
More muscle growth in eight out of nine comparisons
for the higher volume groups. Wow. And here's
the kicker. The only times higher volume didn't
lead to more strength or more growth. Those were
in the few comparisons involving untrained lifters
included in those specific studies. So for trained
people, the trend was clearly higher volume,
more strength, more size. Exactly. It directly
contradicts that whole idea that strength can
stall out early, undermining that core low volume
is enough argument, at least based on this line
of reasoning. OK, that's really important clarification.
But then why do some meta -analyses still seem
to show strength benefits tapering off? Even
if muscle growth keeps going up with volume,
is there another factor? There is, yeah. It's
about training specificity. Think about it. Low
volume training is often super focused. Heavy
weights, maybe just one or two main lifts, very
specific to building maximal strength in that
lift. Right, like power lifting training. Exactly.
Whereas higher volume training, it's often aiming
for both strength and size. So you might use
a wider range of exercises, different rep ranges,
maybe not always lifting maximally heavy on the
main strength test exercise. Ah, so it's less
specific to hitting a huge one rep max on that
one lift the study measures. Precisely. Which
is fine. It's arguably more like how many people
train in the real world, ecologically valid,
as we say. But in a meta -analysis, comparing
strength out comes, that lower specificity can
make the higher volume groups look slightly less
effective for peak strength than they might actually
be overall. Gotcha. So it's not that high volume
doesn't build strength. It's just that the way
strength is often tested might favor the lower
volume or specific approach sometimes. That's
a good way to put it. It influences the results
we see in these big analyses. OK, so we've tackled
the data comparing strength and size gains directly.
But let's go a level deeper. There's this underlying
assumption about why muscles get stronger, right?
The idea that it's all about the contractile
proteins. Yeah, the actin and myosin cross -bridges.
The common thinking is more cross -bridges equals
more force. End of story. But you're saying maybe
not the end of the story. Definitely not. That
premise, that strength capacity is solely down
to the number of cross -bridges is actually false.
There's more to it. Like what? What else contributes
to how strong a muscle actually is? Well, a big
one is connective tissue adaptations. These improve
something called lateral source transmission.
Lateral force transmission. OK, break that down.
Think of it like this. The muscle fibers generate
force. Right, but that force has to get transmitted
outwards through the connective tissue layers
surrounding the fibers and the whole muscle Eventually
pulling on the tendon and bone. Okay, like the
force needs a pathway out exactly and resistance
training strengthens that pathway It increases
specific proteins at the points where fibers
attached to this connective tissue matrix This
directly makes the whole muscle better at transmitting
force independent of just the fibers getting
bigger, huh? So the scaffolding gets stronger
too. Precisely. And this isn't some new wild
idea. Scientists were talking about this back
in like 1989. Wow. And here's a potentially related
really cool idea. Challenging high -volume training
might actually cause tiny temporary unstickings,
adhesions between the muscle fibers and their
surrounding connective tissue. That sounds bad,
like damage. Well, it might involve a protein
called tenashin C. and it seems to be part of
the repair and remodeling process. It might temporarily
reduce strength capacity a tiny bit while things
get rebuilt. But it's likely necessary for strengthening
that extracellular matrix, the scaffolding, which
ultimately allows the muscle to handle more stress
and continue growing. So paradoxically, while
your muscles are growing, they might also be
undergoing these connective tissue upgrades that
could cause temporary dips in strength capacity.
So strength isn't just size, it's also how well
the whole structure works together. And improving
that structure might involve temporary trade
-offs. That's complex. It is. It shows that the
relationship isn't as simple as, bigger, you'll
always stronger right now. This whole discussion,
you know, really highlights a bigger point about
how we understand things in fitness and maybe
science in general. This tension between, like,
logical arguments and actual hard data. Absolutely.
It's kind of a classic philosophy of science
thing. Rationalism versus empiricism. Explain
that. So rationalism is building arguments based
on logic, premises, known mechanisms. A leads
to B. B leads to C. Therefore, A leads to C.
A lot of common fitness beliefs are built this
way. They sound logical. OK. And empiricism.
Empiricism is about observation and measurement.
It's about the data. What do experiments actually
show? In science, especially experimental science
like exercise phis, empiricism is ultimately
the decider. Can you give an example? BCAAs are
a great one. Branched chain? Branched chain amino
acids. Logically, you could argue they should
help muscle growth, right? They're involved in
protein synthesis, they might reduce breakdown.
Yeah, sounds reasonable. When you actually test
empirically, study after study shows taking extra
BCAAs doesn't really help people build more muscle
compared to just getting enough total protein.
So the logic seemed sound, but the data didn't
support it. Exactly. And that's where pseudoscience
often lives in plausible sounding logical arguments,
while ignoring or dismissing the direct evidence.
Empiricism forces us to confront reality. So
the takeaway is, trust the data even if it contradicts
a logical theory. Pretty much. Rationalism is
great for generating hypotheses, ideas to test,
but empiricism is what confirms or refutes them.
It's how our understanding evolves, sometimes
slowly, piece by piece, based on evidence, rather
than sticking rigidly to a logical conclusion
that the data doesn't back up. Okay, applying
that empirical lens then. But let's go back to
the high -volume arguments. What about that common
counter -argument? Oh, the extra size you see
from high -volume, it's just temporary swelling.
It's edema. It's not real muscle. Right. That's
a classic rationalist -sounding dismissal. But
what does the data say? Yeah, what does it say?
Well, muscle swelling does happen right after
a workout, sure, especially if it's new or unusually
hard. But studies show it decreases pretty rapidly
as you adapt. How rapidly? Within, say, 24 to
72 hours, it's largely resolved. We have recent
studies confirming this. Even with really brutal,
eccentric training protocols, untrained people
adapt pretty quickly, maybe within eight weeks
or so. All the markers of damage and inflammation
go way down. OK, so the swelling effect is mostly
short term, especially once you're adapted. Yes.
And here's the really crucial empirical point.
The effect of training volume on hypertrophy
actual muscle growth becomes more obvious in
longer studies. Well, longer studies. If swelling
was the main reason high volume looked better,
you'd expect the opposite, right? You'd expect
the difference to be biggest in short studies
before the swelling resolves or people adapt.
Ah, good point. But we see the opposite. Exactly.
The fact that the benefit of higher volume is
clearer over longer durations strongly suggests
it's causing actual tissue growth, not just temporary
puffiness. The empiricism refutes the it's just
swelling argument. OK, makes sense. What about
the other related idea, sarcoplasmic hypertrophy?
Is that just fake muscle or puffiness too? Yeah,
it often gets lumped in with swelling. Sarcoplasmic
hypertrophy is the idea that the non -contractile
parts of the muscle fiber, the fluid, glycogen,
mitochondria, et cetera, increase disproportionately
compared to the contractile proteins. So bigger
fibers, but not necessarily proportionally stronger.
That's the idea. The sort of strongest indirect
evidence for this came from a study back in 2015.
It suggested bodybuilders had muscle fibers that
produced less force for their size, but that
study has largely been refuted. A follow -up
study in 2021 found some methodological issues
with the original research. Oh, like what? It
seems the apparent difference in force production
was likely an artifact, basically. the fibers
were swelling up during the measurement process
itself, making them look bigger and weaker than
they really were. Ah, so a technical issue with
how they measured it. Exactly. So our understanding
of sarcoplasmic hypertrophy as a distinct major
phenomena, it's still pretty fuzzy, honestly.
So we don't really know if it's a big factor?
We don't. There are hypotheses. Maybe it's temporary.
Maybe it happens before myofibrillar growth kicks
in. Maybe it happens only when fibers get really
big. But it's also incredibly hard to measure
accurately. Think about it, muscle biopsies take
a tiny, tiny sample, try to precisely measure
the proportion of contractile versus noncontractile
stuff in that tiny sample and then extrapolate
to the whole muscle. It's really challenging.
So the it's just circle plasmic argument doesn't
have super strong evidence behind it either not
really strong direct evidence No, the bulk of
the evidence still points towards higher volumes
leading to more actual contractile tissue growth
over time Okay, so bringing this back to practical
advice based on the data We do have where does
the evidence seem solid in terms of weekly sets?
Is there a number we can feel confident about?
Yeah, looking at where the data is reasonably
dense, we can be pretty confident recommending
up to around, say, 25 sets per muscle group per
week. 25 sets. Beyond that point, the studies
become much fewer and farther between, so our
confidence level in making recommendations naturally
drops off. Right. But what about the upper limit?
You mentioned studies going up to 45 sets still
showing benefits. Is there any evidence for that
inverted U where doing too much actually makes
you grow less? Has any study found that yet?
That's the million -dollar question, isn't it?
The honest answer is, we don't have clear evidence
for that downturn yet. Really? Not even at 45
sets? The studies pushing those high volumes,
like 30, 40, 45 sets, they still generally show
more growth compared to lower volumes. Now, theoretically,
that inverted U should exist, right? You can't
just add sets infinitely. Yeah, eventually you'd
just break down. Exactly. But based purely on
the hypertrophy data published so far, we haven't
clearly identified that peak and downturn. Maybe
the next study will find it. But for now, the
limit seems to be higher than previously thought.
Certainly higher than that old 10 -20 set idea.
Speaking of that 10 -20 sets, where did that
recommendation even come from? It feels like
it was everywhere for a while. It really was.
But it was never based on super strong direct
evidence showing that's the optimal range. It
seems to have stemmed from maybe a bit of a lazy
interpretation, as some have called it, of a
2017 meta -analysis. Or so. That analysis basically
just lumped everything above 9 or 10 sets into
one single high -volume category. It didn't really
differentiate between 12 sets, 20 sets, or 30
sets. Ah, so it just showed more than 10 is better
than less than 10, but not how much more is better.
Pretty much. And critically, during that period,
there were a couple of influential studies that
did seem to support lower volumes, like maybe
5, 10 sets being optimal. OK. But those studies
were later retracted because the data was found
to be fabricated. Wow, seriously. Fabricated
data. Yeah. And the time between when those studies
were published and when they were retracted definitely
skewed the perception and contributed heavily
to that 10, 20 sets is probably enough consensus.
Remove those faulty studies and the picture looks
quite different. OK, that context is really important.
But let's talk feasibility doing, say, 30 plus
sets per muscle group. for all your muscle groups.
That sounds like living in the gym. Is that even
realistic? It's definitely a significant commitment,
no doubt about it. When you look at surveys of
competitive bodybuilders, you do see some reporting
volumes in that 30 -40 set range per muscle group
per week. Some do it, okay. But it's not the
norm. The typical range reported is usually more
like 12 to 24 sets. And the research we have
doesn't strongly suggest high volumes only work
if you focus on one or two muscles. Studies often
have participants train multiple muscle groups
with high volumes and see benefits across the
board. But the downsides? Time, obviously. It
takes a lot longer. And importantly, a higher
risk of joint aches, tendon issues, that sort
of thing, especially if you jump into it too
quickly. So slow and steady ramp up is key if
you try it. Absolutely crucial. We're talking
gradually increasing over maybe three to six
months, not trying to double your volume overnight.
Your connective tissues need time to adapt. You
mentioned earlier that not everyone responds
the same way, though. Can you elaborate on that?
Why might higher volumes work wonders for one
person, but not another? Right. Individual response
is huge here. While on average higher volume
leads to more growth, the spread is wide. You
might have roughly a quarter of people who respond
dramatically better to high volume. Okay. Maybe
another quarter see a moderate improvement. Another
quarter might see no real difference compared
to moderate volume. And then maybe another quarter
actually do better on lower volumes. A quarter
doing better on lower. Interesting. Why the difference?
We don't know for sure, but there are potential
reasons. Genetics play a role, obviously. Differences
in things like ribosome biogenesis, how quickly
your cells can build proteins. Satellite cell
excavation, those are muscle stem cells involved
in repair and growth. Fiber type distribution
could matter too. People with more fatigue resistant
type I fibers might tolerate and benefit more
from higher volumes. Type I, the endurance fibers.
Yeah, but they still grow quite a bit. And then
there's the real world factor. In a controlled
study, people might be pushed harder than they
typically push themselves in their regular training.
Maybe some people just don't maintain the necessary
intensity when volume gets really high on their
own. That makes sense. So genetics, fiber type,
maybe even just practical effort levels. Given
that high volumes can work, at least on average,
why don't we see more people doing like 40 plus
sets routinely in gyms everywhere? Besides the
time factor you mentioned time is probably the
biggest practical barrier. Let's be real getting
maybe 20 % better results But spending 50 % more
time in the gym that trade -off isn't worth it
for most people who aren't competitive bodybuilders
Yeah, the diminishing returns hit practicality
hard Exactly. And there might also be a systemic
recovery issue, even if each individual muscle
could handle more. Maybe your overall system,
nervous system, endocrine system, joints hits
a recovery bottleneck when you try to push everything
super hard simultaneously. Like a total body
stress limit. Potentially, yeah. It's easier
to blast one or two body parts with insane volume
than it is to do it for everything all at once,
week after week. OK, another question. These
studies are often, what, 8, 10, 12 weeks long?
They might show, say, 10 % more growth with high
volume in that time. Can we just extrapolate
that out? Does that mean you'll gain 10 % more
muscle every three months than definitely if
you stick with high volume? Ah, no, definitely
not. Muscle growth isn't linear like that. It
follows more of a logarithmic curve. Meaning
it slows down over time. Exactly. Your gains
are fastest when you're starting out or recovering
lost muscle, and they slow down progressively
as you get closer to your genetic potential.
Higher volume seems to lead to faster gains,
especially early on. So you get more growth sooner?
Yes, and likely more total growth over, say,
the first year or two compared to lower volumes.
But it's possible that over a very long time
frame, like five or 10 years, the total amount
of muscle gain between someone doing moderate
volume versus high volume might start to converge
somewhat as they both approach their genetic
ceiling. Hmm, interesting. But very low volume
would still be lagging behind. Oh, yeah. Very
low volumes, like just a few sets per week, are
almost certainly suboptimal for maximizing long
-term growth for most people. What about volume
cycling? You hear about people increasing volume
for a while, then backing off to resensitize,
then pushing up again. Is there anything to that?
That's an interesting theory. The idea is based
on progressive overload that you need continuously
increasing stress. So maybe Constantly pushing
high volume leads to accommodation, but cycling
yet allows you to keep adapting. Does the evidence
support it? There's some indirect physiological
rationale, maybe some suggestive findings, but
no really definitive studies validating volume
cycling as superior to just maintaining a consistently
appropriate volume yet. However, even if cycling
turns out to be beneficial, the principle likely
still holds. Training with generally higher volumes,
even if you cycle them down periodically, seems
to be more effective than training with consistently
low volumes. So the baseline average volume still
matters? It seems to. Okay, let's revisit the
mechanism. At the most basic level, how does
doing more sets lead to more muscle? Is it just
more stimulus, more growth? That's the simplest
and likely largely correct answer. A greater
total stimulus triggers a greater adaptive response,
up to a point. Is there any more nuance to it?
Potentially. One idea relates back to fiber types.
Higher volumes, often involving more reps and
maybe shorter rests, might be better at stimulating
those fatigue -resistant type I fibers. Which
you said contribute significantly to overall
size. They really do. They might be underestimated
in traditional strength training. Also, think
about the bioenergetics, the energy systems within
the muscle. Things like capillary density, more
blood supply, and mitochondrial function, energy
production, are crucial for supporting muscle
growth. Higher volumes might promote these adaptations
more effectively, removing potential metabolic
roadblocks to fibers getting bigger. So it's
not just triggering the growth signal, but also
building the support systems needed for that
growth. That could definitely be part of the
picture, yeah. We talked about strength versus
size earlier. How good is tracking your strength
gains as an indicator whether you're actually
gaining muscle, especially in these shorter time
frames like a typical study? It's tricky. Over
the long term, for a specific individual who
is already trained and consistent with their
technique, tracking strengths can be a reasonably
good proxy for hypertrophy. If your lifts are
consistently going up over months and years,
you're probably gaining muscle. Okay, long term
it works better. But in the short term, like
those 8 -12 week studies, strength is often a
poor indicator. Why? Because as we discussed,
those early strength gains are so heavily dominated
by neural adaptations, just getting better at
the lift. The point where hypertrophy becomes
the main driver of strength increases is probably
around that 8 -12 week mark or even later for
some exercises. Right, when the study often ends.
Exactly. Plus, in smaller studies, you get more
random variation sampling variance. One small
study might show strength going up without much
size gain. Another might show the opposite, just
due to chance or measurement error, even if the
underlying relationship across many studies is
clearer. So don't put too much stock in week
-to -week strength changes as proof of muscle
gain, especially early on. Generally, no. Look
at longer trends. Let's talk about diminishing
returns again. You said higher volume leads to
more growth, but with diminishing returns. Can
you clarify what that means? Does diminishing
returns mean it's not worth doing? That's a common
misunderstanding. Diminishing returns just means
each additional unit of input gives you less
output than the previous one. OK. So maybe going
from 5 to 10 sets gives you x amount of growth.
Going from 10 to 15 sets gives you less than
x, maybe 0 .7x. Going from 15 to 20 gives you
even less, maybe 0 .5x. Right, the benefit per
set decreases. Yes. But importantly, diminishing
returns does not mean lower total returns. In
that example, 20 sets still gave you more total
growth. x plus 0 .7x plus 0 .5x, then 10 sets,
just x. Ah, okay. So even though the efficiency
per set goes down, the total result can still
go up. Exactly. So the goal of maximizing efficiency,
most growth per set, often favoring lower volumes,
and the goal of maximizing total results, most
growth overall, often requiring higher volumes,
can be contradictory. And people need to decide
which goal is more important to them considering
the trade -offs. Precisely. Time, effort, injury
risk, recovery capacity, all need to be weighed
against how much growth you're aiming for. OK,
so let's try to synthesize all this. What's the
practical recommendation for someone listening?
How should they figure out their ideal volume?
Well, first things first. If what you're currently
doing is working, if you're consistently making
progress, you're happy with don't change anything.
Don't fix what ain't broke. Exactly. A bird in
the hand is worth two in the bush. Don't mess
with success just because some studies suggest
something else might be slightly more optimal
on average. Good advice. But what if you have
plateaued, or you feel like your progress is
way slower than you'd like? Then, based on everything
we've discussed, increasing your training volume
is a very valid evidence -based strategy to try.
How should someone approach that? Just double
their sets next week? Definitely not. Gradual
increase is key. A reasonable starting point
might be to aim for about a 20 % increase in
weekly sets for a target muscle group. 20%, okay.
And then what? Stick with that for maybe two,
four weeks. See how recovery feels, then maybe
add another 20 % if things are going well. Do
this gradually over, say, two, three months.
And how do you know if it's working? Monitor
your progress objectively. Are your training
loads? weight on the bar for the same reps, starting
to consistently exceed what you were doing before
on the original lower volume, that's a great
sign you're responding well. So getting stronger
on the higher volume is key. Yes. If your loads
are just staying the same despite doing more
sets, that's kind of a neutral signal. You're
building work capacity, maybe some endurance,
but perhaps not driving maximal hypertrophy effectively.
And if your training loads actually start to
decrease and stay lower after a couple months
on a higher volume, That's a bad sign. That's
a pretty strong sign that that level of volume
isn't productive for you right now and you should
probably back off or explore other strategies
like changing exercises, improving nutrition,
or focusing on recovery. What about those specialization
blocks you mentioned? Yeah, focusing high volume
on just one or two muscle groups for a period
while maintaining lower volume elsewhere can
be a great way to test your individual response.
It gives you a clearer signal because you're
not trying to push everything at once. It's about
finding your sweet spot through careful experimentation.
Exactly. The goal isn't necessarily to hit some
magic number like 25 sets or to do the absolute
maximum volume you can possibly tolerate. The
goal is finding the amount of volume that you
need to stimulate the progress you want, balancing
results with recovery, time, and enjoyment. Individual
context is everything. Wow, okay, we really went
deep today. We unpacked why those old assumptions
about strength plateaus limiting muscle growth
don't really hold up when you look closely at
the data, especially for trained individuals.
Yeah, we saw that higher volumes generally do
lead to more growth and importantly more strength
gains, too, contrary to some interpretations.
And we touched on the role of connective tissue,
that strength isn't just muscle fiber size and
the importance of relying on empirical data over
just logical arguments. Definitely. Trusting
the data, even when it's complex or contradicts
old beliefs, is key. This whole exploration,
it's more than just how many sets should I do.
It's really about thinking critically, right?
Applying these scientific principles to your
own training journey. Absolutely. And maybe it
prompts a question for you, the listener. If
your goal is to optimize your progress, What
aspects of your current routine are you just
taking for granted based on old assumptions?
Yeah, what new possibilities might open up if
you looked at your training with this fresh evidence
-based perspective we've discussed today? Something
to think about. Keep exploring, keep questioning,
keep learning. Couldn't said it better myself.
Thanks for joining us on the Deep Dive.