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If Cortisol Is So Important, Then Why Is Volume Considered The Main Driver of Hypertrophy?

The articles of CT all say for naturals too much volume is the main problem. Yet, guys lime Brad Schoenfeld, Greg Knuckols, and so many other knowledgeable guys out there say that volume is king when it comes to hypertrophy.

More volume= more gains

My question to CT is, when you say that volume is a big problem for naturals, are you specifically talking about the guys who aren’t properly recovering from their workouts?

Or are you saying that irregardless? If so, then what do you have to say about all the evidence showing that when all else is equal, more volume that you can recover from will lead to more gains.


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Intrested in hearing his response.

CT has stated frequency is king

  1. There is volume and there is VOLUME. Read Brad works. The volume he recommends is actually quite low. We are from from the 20+ sets per body part that you see some bodybuilders doing. I remember Brad saying that 9 sets led to better results than 6 sets which led to better results than 3. And I agree 100% I never said that volume was not required. And yes increasing volume, to a point, leads to better results. But if volume was THE key it means that doing more and more and more would lead to better results. Which is simply not the case in natural trainees. Yes going from 3 sets per body part to 6, 9 and 12 will give you better results, no doubt. But that is not true if you simply continue to pile on volume… 20, 30, 40 sets will not lead to more growth in a natural trainee.

  2. Brad talks about volume per week mostly. He stated that training a muscle twice per week is better than once per week, and that hitting 3x per week is very likely better than hitting it twice. And that advanced trainees might benefit from even more frequent stimulations. The overall volume is devided into these 3+ sessions. When he refers to high volume per muscle it is the total weekly loading for a muscle.

  3. I DO believe that more volume = more gains AS LONG AS YOU CA ADAPT POSITIVELY TO IT. And adapting positively to a training stimulus is depends to each person. Some people can adapt to a lot of volume (e.g. those who naturally produce less cortisol and/or have more androgen receptor sensitivity or higher level of anabolic hormones… or those who artificially increase their protein synthesis and decrease protein breakdown by taking drugs). Some people overproduce cortisol (naturally more anxious individuals or those with crazy work/life schedules and lots of stress). Some people have lower levers of anabolic hormones. These two types will NOT be able to positively adapt to as much volume as others not in that situation. When you train you increase BOTH protein synthesis AND protein breakdown (mostly via cortisol and adrenaline). The key to muscle growth is having protein synthesis being higher than breakdown.Those who overproduce cortisol and/or have lower levels of anabolic hormones will have a higher amount of breakdown in response to training PLUS if they tend to overproduce cortisol throughout the day (stressful life, physical job or being naturally anxious people) then their rate of protein breakdown can be elevated throughout the day. And again if the difference between synthesis and breakdown is small or negative) then you wont build as much muscle. To make it simple YES doing more volume will lead to more gains IN THEORY. BUT the amount of volume each person can tolerate is dependent on their own biochemistry. So while increasing volume, as long as you stay where you can positively adapt to it, will give you more gains. If you do too much volume for your body, you will have lowered progress and maybe even regression. Remember that the more you train the more protein breakdown you cause. And the more you tend to produce cortisol (or the more sensitive you are to it) the more your breakdown is increased to. That’s why too much volume can kill your gains, even if in theory more volume = more gains.

  4. Brad’s greatest strength is also his greatest weakness: he base everything n studies. That’s not wrong. But studies are not 100% applicable. The one thing that jump to mind is that studies rarely use what WE (serious lifters) consider HIGH volume. Look at most studies about volume: they compare 1 set vs 3. Or maybe 3 vs 6 or vs 9. I’ve never seen studies use “REAL LIFE” high volume… 20-30 sets per body part for 2-3 body part per sessions or something like that. I’, NOT against volume. I personally do more than 12 sets per body part in a session. But to me 12 sets per muscle is NOT high volume. Now of course studies will see more gains with 3 sets vs. 1… or with 6 sets vs. 3 or 9 sets vs. 6… because that is still pretty low volume and most can positively adapt to that. The mistake is coming to the conclusion that since 3 sets is better than 1, 6 better than 3 and 9 better than 6 then adding more volume will always lead to more gains. It won’t. Well it will if you have the biochemical nature to positively adapt taking tons of drugs for example). But with natural trainees there will be a point when adding volume stops leading to more gains. And another point where adding even more volume could even lead to regression.


DUDE, you are trying to create a disagreement with “experts” that doesn’t exist. I agree with that sentence 100%

In fact I said that MANY TIMES in the past in my forum. But the key is “that you can recover from” . See my answer above.

And different people can handle different volume. And why do you think that is? Why are some people capable of positively adapting to a lot of volume and others aren’t? Cortisol vs. anabolic hormones. mostly.

People who overproduce cortisol (higher natural anxiety levels, lower levels of serotonin and/or GABA) or produce cortisol around the clock (stressful lifestyle, relationship issues, very physical job, etc.) will have much higher rate of protein breakdown and will also tend to become more insulin resistant. Plus chronically elevated cortisol levels can increase the expression of myostatin. All of these can limit how much muscle you will build and how much volume you can tolerate.

If someone has high testosterone levels (naturally or via enhancement) and//or high IGF-1 levels (naturally or via enhancement) and produces less cortisol he will be able to positively adapt to a lot more volume.

We are all saying the same thing. YES doing more volume, as long as you can positively adapt to it, will lead to more gains. BUT your capacity to adapt depends on your own biochemistry, a huge part of which is cortisol level and sensitivity.

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Thanks very useful replies.

Could the naturally high-cortisol individual also have difficulty in losing fat or gaining muscle with right diet and exercise 1) due to low GABA and low serotonin or 2) due to overproduction of cortisol? or both elements together?

What interests me if neutro-transmitter balance, ever have a role in fat loss or muscle gain?


Low GABA and low serotonin actually contributes to increasing cortisol levels.

Why? Because both of these neurotransmitters help you relax. Basically they reduce neural activity which relaxes you. If you increase neural activity (via adrenaline or dopamine for example) BUT cannot bring it back down (because you don’t have enough serotonin or GABA) you stay in “fight or flight” mode, even after the stress has passed. That keeps your body pumping cortisol.

Cortisol is a mobilization hormone. So technically it should make you leaner, not fatter… right?

Acute cortisol increase, yes. If it goes back down. But chronic cortisol elevation can make you fatter or make it harder to lose fat.

First because chronic cortisol elevation inhibits the conversion of T4 into T3. T4 is an inactive thyroid hormone while T3 is the one that has the greatest impact on metabolic rate. You have very little T3 and you produce what you need to maintain a normal metabolic rate by converting T4. BUT cortisol reduces that conversion. Meaning that chronic cortisol elevation can lower metabolic rate.

Furthermore chronic cortisol elevation can lead to insulin resistance. When you are insulin resistant it’s much harder to get leaner and build muscle. It’s also easier to gain fat.

Cortisol elevates blood sugar level. Insulin lowers it. Your body wants to stay in the 4.0 - 5.0mmol/dl. When cortisol is chronically elevated your blood sugar levels always goes up… if that happens when you are not physically active your body has to lower blood sugar levels by releasing insulin. So when cortisol is always high, you always have to compensate by releasing insulin to lower back down blood sugar levels. That can easily lead to insulin resistance.

So yeah, low serotonin/GABA and excess cortisol will make it much harder to get lean and build muscle

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What you explain makes a lot of sense Coach, thank you very much for your reply.
I find most of your articles have valuable and up-to-date information in health, training, nutrition.
Thank you very much again. Have a great day.

Anytime! I just gave a seminar on that same topic yesterday so it writes itself!

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A little studying on Cushings syndrome will show you the extreme side of chronically elevated cortisol levels.

Coach, what do you think of the research showing increased GH and IGF-1 production, along with significantly reduced cortisol levels, via supplementation with betaine?

In addition to CT’s great response, having high insulin will block growth hormone secretion. Ironically, having some carbs in the evening can lower insulin by lowering stress hormones and therefore boost night time GH release which causes repartitioning to favor muscle. Another advantage of morning versus evening training. And lastly I’ll mention that any more than1 alcohol beverage in the evening makes the liver insulin resistant for several hours into the night.

It is critical for wellbeing to get cortisol down during the first 2-4 hours of sleep. And poor sleep chronically raises cortisol.

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VERY interesting!

I’ll add that switching to AM training like you suggest has helped me progress and sleep better. Also the idea of having some carbs in the evening. Now I get carbs around my am training, but I will add some in the evening like some fruit, but I will go on a brisk walk to raise insulin sensitivity either right before or after to make my insulin work more efficiently.

I am also much interested in this subject. I am 2B type and I worry a lot and feel stressfull often (even when there are no circumstances for that), and not sleeping very well. I have had really slow and dissapointed progress in terms of body composition and especially gaining muscle despite gaining weight and lifts poundages improvement and REALLY prioritise nutrition and training quality and discipline.

Once I started to understand about neuro types, it really had a lot of sense, I changed my training(especially in terms of volume) and feeling much better about it. I still have recovery issues, but at least now I understand it so I know what I am fighting against and why. (fighting is probably not a right word but it doesn’t reflect my “high cortisol fight or flight mode” but because english is not my native language :smiley:

So, thank you Christian for this explanation and all your great work and all your help here :slight_smile:

Hogar what was your training like before and what have you changed it to?

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Interesting. I’d like to know more about this. Do you have a source?

Anecdotally, I can vouch for this. I have no idea what this is doing to my cortisol levels exactly, but I do fall into a deeper sleep more quickly when I have carbs and a bit of fat before bed.

As always, great insights. I’m wondering what your thoughts are on sub-maximal sets for strength. Seems you’d be able to accumulate more volume (sets per week) without raising cortisol to harmful levels if you go this route. Would you consider this the optimal approach for strength gains?

CT covers that here.

He also has a nice video where he discusses this on his ThibArmy site.

The alcohol effect is demonstrat d by a couple of different groups of studies-basically one group of studies showing what alcohol does to upregulation of triglyceride production and the other on what triglyceride production does to insulin requirements, so I’ll try to dig up something that shows both effects. Other studies clearly show that more than 25 grams of alcohol per day causes increase in liver fat which is what causes liver insulin resistance primarily in metabolic disorder. High triglycerides are the surest sign of metabolic syndrome and alcohol and excess fructose are the substrates in the body that HAVE to get turn d into triglycerides to avoid toxicity.

Regarding night carbs, remember that you need to get cortisol down in part so that your body will not oversecrete insulin in the first part of th in large part because high insulin blocks the natural growth hormone release at that time. The lack of GH results in cumulative micro trauma to muscles and connective tissues which makes you secrete even more cortisol as an anti-inflammatory. The cortisol makes you need even more insulin and blocks GH ev n more. Point is, a few carbs are good if they reduce cortisol, but not if they are enough to require a large insulin release to manage blood sugar because the insulin will block GH even if you bring cortisol down.