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The Hormonal Response to Squats and Muscle Growth

For literally decades, the idea that the hormonal response to squats is important for overall growth has been around.  It came up again recently in my Facebook group and I wanted to address (and ultimately dismiss it) yet again.  First,  Consider the following two statements:

  1. You have to squat (or more generally train lower body) to get big.
  2.  What’s up with all those guys in the gym with big upper bodies and no legs?

I’ve seen the same person make both statements without realizing that they inherently contradict one another.  If you need to train legs to get big overall, you can’t have guys with big upper bodies who don’t train legs.  It’s not difficult to see why this is wrong.  And yet many continue to repeat both statements.

Squats vs. Leg Press for Big Legs

Years ago I wrote an article arguing that, for some people, the leg press will be a superior exercise choice in terms of building legs than the squat.  My basic argument is that, for people with poor squatting mechanics, it will be a losing cause.  People with long femurs who end up very tipped over will always have their low back fail long before their legs.  Squats will do jack squat (ha ha) for them.

This wasn’t to say that squats were a poor choice for everyone.   Rather, it was to point out that exercise selection is a little more nuanced than “Compounds and free weights rool and machines and isolation work drool.”  Good luck telling that to the zealots.  Some people are built to squat well for training their legs.  I’m one of them.  I have short femurs and can stay very upright.  Well before I broke my leg anyhow.  Now my left ankle doesn’t bend that way.

But that’s simply not the case for everyone.   This is actually true of all exercises and the simple fact is that only powerlifters, Olympic lifters and maybe strongman competitors have to squat since it’s part of their competition package.  For everyone else, it’s not required.

That article went over about as well as you thought it would and you can read the comments for true hilarity.   Most of them are just a lot of macho horseshit which is 80% of what the fitness industry runs on.  But invariably someone will bring up the hormonal response to squats to argue why they are superior.

And this happened more recently in my Facebook group.  Someone brought up that leg press vs. squats article and, as is always the case, the thread was inundated with a lot of your typical crapola.  Just people justifying their hardon for squats with the silliest of arguments.  It is always the way.

And of course someone invoked the hormonal response.  I was away from the computer and didn’t get to address him directly but everyone made the point for me and he removed himself from the group.  Which was just fine.

So what point was made for me?  Well, it has to do with this long-held idea that squats (and other movements such as deadlifts) are inherently superior for “all-over growth” due to some systemic physiological response.  That idea has been around for decades to begin with although the supposed physiological reason, the hormonal response to training, is only a few decades old.

Squats Hormones and Growth: Part 1

Now, the general argument for the whole squats/lower body training and growth has to do with the hormonal response to training. This was an idea that came around in the 80’s and has kept going since then.

And not only did it provide what I consider a red herring for training for the past 4 decades but showed how not to do science.  Researchers had observed that, generally speaking, bodybuilders of the day were bigger than powerlifters.  We might debate this but let’s roll with it.

Thus it was assumed that the different types of training played a role.  Ok, not bad so far.  And this is where it went wrong: having decided that the training was the primary impetus for the differences, researchers wanted to see why it worked that way.  Effectively they started with a preset conclusion and then worked backwards to the data to support it.  That’s not how you even science and yes I linked out to Maddox.

So they did the studies.  They set up what they considered stereotypical power or bodybuilding training and most studies compared something like 3X5RM (repetition maximum) with a 3′ rest to 3X10RM with a 1′ rest (at the time most bodybuilders trained in a fairly fast paced pump style). And they measured the hormonal response to the training.  Invariably the power training caused a spike in testosterone and the bodybuilding training caused a spike in Growth Hormone (GH).

A variety of studies were done on this theme with different movements and such; big movements worked better than smaller muscle mass movements and there were just endless variations on a theme here.  Without getting into details, let me just focus on the general hormonal response picture.

Now, maybe they didn’t know it then (which I doubt) but we sure know now that testosterone is far more anabolic than GH which, by itself at least, does less than jack squat for growth unless you’re correcting a GH deficiency in children or something.    Yes, great for connective tissue, may help with fat loss.

For growth, unless stacked with other drugs, it does 3/5ths of squat and possibly less than that.  Testosterone on the other hand is hugely anabolic, building muscle even without training.  So already the researchers were off the rails and their observations actually contradicted their starting concept.

If bodybuilders are bigger than powerlifters but powerlifters get an increase in the actually primary anabolic hormone in the first place while bodybuillders get a bump in an irrelevant hormone, then the whole idea simply fails.  By their own logic the powerlifters should be more muscular.

They seemed to have ignored that (they also either ignored or were unaware that on top of differences in training of elite bodybuilders and powerlifters, there were already differences in the types of drugs being used).

Hell, perhaps irrelevantly, consider that women have higher GH levels than men (and show a greater GH response to training) but 1/10th to 1/30th the testosterone levels.  Do they grow better?  Exactly.  Because GH levels or the small increase in training is meaningless by itself.

But people continued to focus on this for a while, I remember having arguments ages ago with people about this.  A favorite argument made to me “Lyle, if anabolic steroids work so well, why is the transient increase in testosterone so irrelevant in your opinion?”

Hell, that’s easy.  “Because raising a hormone to supraphysiological levels all day every day is obviously not the same as a small spike that lasts like 15-30 minutes.”   Raising testosterone by 30 ng/dl over normal for 30 minutes is not the same as raising it by 1000 ng/dl 24 hours per day.  This also doesn’t seem terribly hard to understand.

 

Squats Hormones and Growth: Part 2

Now I have written about this topic before and the fact is that studies still seem to disagree on whether or not the small hormonal response to training does or does not matter.  Mind you, they did use different protocols, one trained legs before and the other after but the effect even in the study that did find an effect was small overall.

More directly a paper by West and Phillips found that the hormonal response to training only explained 8% of the variance in Type II fiber growth.  But here it gets weird because it was GH and cortisol that were related.  The testosterone response was unrelated to growth.  Ok….   Even here, when they divided subjects into high and low responders they found:

We found that the hormone responses of individuals who were responders (defined in “Statistical analyses”) for gains in LBM, fibre area and leg press strength were no different from the hormone responses of non-responders. Phrased simply, subjects at the top ~16% in terms of resistance exercise phenotypic responses were no different from those at the bottom ~16% in terms of the acute response of testosterone, GH, IGF-1 and cortisol.

So whether or not the hormonal response was high or low explained nothing in terms of the response to training (I’d note that they did use untrained individuals).

Basically, if there’s an effect it’s very small overall.  In my opinion it’s certainly not worth chasing if it means changing your workout from something effective to something contrived to “maximize hormonal response”.  That’s called missing the forest for the trees.

To put this in even starker perspective, there is a recent meta-analysis which examined a ton of papers on the topic and concluded that the average increase in testosterone was roughly 29 ng/dl for no more than 30 minutes.  Now, the normal testosterone range for men is 300- 900 ng/dl (some go higher than this).  So that’s a 3-10% increase in testosterone for a whopping 30 minutes maximum.

Hormones in Perspective

Let me put that into further perspective.  Raising testosterone by 29 ng/dl is roughly the equivalent of injecting 2.9 mg of testosterone into the body.  That’s not a typo.  2.9 mg.  A baby dose of anabolic steroids is 100 mg/week.  HRT is usually 150-200 mg/week.  Bhasin studied 600 mg/week.  And there are athletes taking 1000 mg/day.

Hilariously, this paper was titled:

Endogenous Transient Doping: Physical Exercise Acutely Increases Testosterone
Levels-Results From a Meta-Analysis

Raising blood testosterone levels by the equivalent of 2.9 mg of injectable testosterone is not doping.  It’s irrelevant.

Even a low dose of anabolic steroids raise testosterone many fold times more than that.  Take someone who is hypogonadal and put them on even 150 mg of testosterone per week and their testosterone might go from 200 ng/dl or less to 450-500 ng/dl.

Supraphysiological doses of testosterone can raise it many fold above the normal range.  In Bhasin’s original study, 600 mg/week of testosterone raised levels to 3000 ng/dl, triple the normal range.  And those levels were measured 1 week after the injection (this is why it’s not 10 fold higher).  Measured a day or two after the injection, they would likely have been in the 5000-6000 ng/dl range, a 5-6 fold increase over normal levels.

Bhasin Supraphysiological Testosterone Respones

That’s a 2000-5000 ng/dl increase in testosterone from a single 600 mg injection

And this paper thinks raising testosterone by 2.9 mg for 30 minutes is doping.

It’s not doping.  It’s not even relevant.  It doesn’t matter.  And it does nothing.

And that’s because…

Growth is Local

The fact of the matter is that the muscle growth response is primarily local, a combination effect of  tension, fatigue, maybe damage. And there is absolutely a local hormonal response that is crucially important.

Researchers years ago identified an IGF-1 (Insulin Like Growth factor-1) analog in muscle called Mechano Growth Factor (MGF) that was crucial to the anabolic response.

Tangentially, I think they missed a trick with this one: Muscle Growth Factor, Massive Growth Factor, Motherf*****huge Growth Factor would have been far awesomer.   But I digress and this was before scientists thought that they should be comedians by naming stuff with silly names (there are genes like Sonic the Hedgehog, Clark Kent and Superman).

And if you’re wondering what stimulates MGF release?  Well, as the name suggests it’s mechanical tension.  Because mechanical tension is what stimulates growth.

Squats Hormones and Growth: Part 3

Now despite my comments at the start of this piece regarding guys with big upper bodies and no legs (which you can see in every gym), it is generally true that guys who squat/train legs hard are usually pretty big.  So if it’s not the hormonal response driving this, what is?  I’d offer the following:

It’s very common to see guys who train the upper body hard but ignore legs.    And since growth is primarily a local response, they get big upper bodies.  You can’t even argue with this, you can see it in every gym on any day of the week, and it completely contradicts the base idea that you have to train legs to get big.  Yes, the hardheads argue, but how much bigger would they be if they trained legs?  Stop.  Just stop.

But have you ever seen a guy who trained legs hard, I mean hard, I don’t mean pansy-assing through a few sets of half squats and leg curls,  I mean training legs hard…have you ever really seen that guy not training EVERYTHING hard including the upper body?

No, you really never have.  I’m sure they exist; but it’s rare.   Anybody willing to put the energy into really training legs hard will put the energy into really training everything hard.  And thus everything grows.  Because training things hard makes them grow.

But the presence of heavy squats are correlational here, not causal so far as I’m concerned.  Guys who train legs hard train everything hard.  And everything gets big because that’s how growth works.
They happen to squat since most guys who train legs hard train squats but it’s in no way causing the growth.

Guys who train upper body hard but not legs only get a big upper body because growth is local and the hormonal response is basically irrelevant.  And you can prove this to yourself by looking at the upper body development of paraplegic athletes.   Some wheelchair athletes have upper bodies that bodybuilders would kill for.  And they get it from training the upper body and the upper body only.

Even if you look at those supposed magic routines that are based around squats, they invariably include a lot of heavy work for everything. So if you take a skinny kid and put them on a diet of squat, bench press, row, OHP and some arm work and tell them to eat, they tend to get bigger. You can give the squats credit but the fact is that training everything hard makes everything bigger.

To that I’d add that squats and deadlifts train more than just the lower body.  The upper and lower back is involved heavily in both movements.  If there is an “all-over” growth response to those movement it’s because they tend to train the body “all-over”.  Growth is mostly local and there is no systemic response in this regard.

Two More Comments

Years ago, debating this with my mentor (you don’t know him, he went to a different school in Canada), he pointed out that he had seen arm growth in folks he trained with nothing but 20-rep squats and no direct upper body work.

That would seem to put me in my place but I’d ask the following question: what holds the bar?   Squats aren’t just a leg exercise, the upper back, torso and yes arms are involved to keep the bar on your back.  They get at least an indirect training effect here so far as I’m concerned.

And if you want me to really kick of a shit-storm, I’d suggest that if someone only wants a big upper body, it’s better NOT to train legs.  Training legs is draining and leaves less energy to train upper body effectively.   If you want a big chest and arms, train your chest and  arms and don’t futz around training legs at all.

Specialists in any sport make better progress than folks who are spread thinner (consider the best performance in any individual sport vs. decathletes or bench press numbers for bench specialists vs. three lift lifters) and the less energy you put into one thing, the more energy you can put into your focus.    That should cause a lovely argument in the comments.

But the bottom line is that squats do not have some magic systemic growth response.  The hormonal response is essentially irrelevant, it’s too small and too short lived to make an iota of difference.  Growth is local in response to local stress of the muscle.