October 24 2009
It has been shown that moderate to high volume workouts, using large muscle group exercises & short rest intervals cause an acute spike in testosterone levels.
Theoretically, these acute spikes in testosterone are claimed to increase muscle growth and strength.Let’s see what the evidence says:
Injection of testosterone has shown to increase muscle mass & strength.
The increase in muscle & strength was also seen without any weight training exercise whatsoever.These studies clearly show the benefit of testosterone on muscle growth & strength.
Limitations: The studies we are talking about use supraphysiological doses of testosterone which are far greater & incomparable to the exercised-induced tiny spikes in testosterone.
Also exercised-induced testosterone spikes do not change the resting values of testosterone;it only lasts for 45-60 min.
Suppression of testosterone has shown to decrease muscle mass & strength in weight training folks
Limitations: The suppressed levels of testosterone in the study reached the levels of hypogonadal individuals.
So the only sensible conclusion we can make from this study is that we need minimum levels of testosterone to maintain/or increase muscle mass & strength.
Resistance training increases testosterone receptors
Limitations: That’s well and good, but it is yet to be shown that a workout program designed to increase testosterone is more effective in increasing these steroid receptors compared to a generic weight training workout.
We are also unsure if this increase in receptors contribute to a greater increase in strength and muscle mass.
Combined leg & biceps training shows greater isometric strength in biceps compared to just biceps training.
Limitations: This study is some scientific proof to the anecdote of how squats can add inches to your arms. The study showed significant increases in testosterone and isometric strength when leg training was added to the arm training.
However, the study did not measure muscle size, the increase in isometric strength could have been due to neural adaptations, and the mean initial strength was higher in the arm group which skewed the results a bit.
Increase in muscle & strength without any exercise- induced increase in testosterone.
Limitations: This study concluded that you only need basal levels of testosterone to promote muscle growth and strength increase.
But it does not reject the possibility that increase in exercise –induced testosterone levels could have increased the muscle growth & strength even further.
What it all means is that we are still not sure if workout routines specifically designed to increase testosterone are effective in increasing muscle and strength than the generic workout routines.
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Jim@TBF | Sat October 24, 2009
It would appear to me the real question is, how much is testosterone increased with these specific workouts over the latter? We all know that supra physiolical doses of T work, however higher levels of T such as those in a teenager improve muscle mass as well. So, just how much additional T does one need to reap the rewards?
Anoop | Sun October 25, 2009
Hi Jim,
The muscle increase with testosterone is clearly dose -dependent. The supraphysiological doses increased serum testosterone levels by more than 600% and they gained around 14 lbs in 10 weeks of muscle compared to 1-2 lbs by the control group.
The exercised-induced increase is only around 25-40% and it only lasts for 30-60 mins. The resting levels of testosterone is not changed which is important to consder when you compare with exogenous administration and testoterone increase in adolescence
I think it is kind of interesting considering how people have experience greater growth with multi joint exercise, short rest, and moderate to high volume workouts. Atleast some of the big researchers, like Kraemer believe in this theory. But we are yet to see some causative evidence to implicate exercise-induced testosterone to help muscle growth.
Jim@TBF | Sun October 25, 2009
It may be that the growth witnessed by Kraemer and others is the sum of several effects, with a temporary rise in T being but one piece?
Anoop | Mon October 26, 2009
Hi Jim,
If that’s the case, then workout programs should be specifically designed to increase testosterone.
But we are not sure if those tiny spikes is even playing a role or is just a worthless association.
And as they say the greatest crime a researcher can commit is to “believe in his hypothesis”. Kraemer is one of the big shots in the exercise field and I hope he doesn’t make that mistake.
Anoop | Tue October 27, 2009
This is one of the top researchers - Indrani Sinha-Hikim, Ph.D - had to say:
“I am positive that your experimental conditions will induce muscle growth. Here two things will happen 1) sustained testosterone spike every day and 2) exercise-induced muscle regeneration .
25-45% T increase for 30-60 min post workouts is huge. Both “T” and resistance exercise will stimulate AKT pathway and probably the muscle will have enlarged fast fibers mostly, though you will definitely see some area increase in slow fibers also.”
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Anatoly | Tue October 27, 2009
Somehow, my comment disappears.
Any way: does Kraemer compares CSA as a result of different types of training or he just measure hormone level?
Anoop | Wed October 28, 2009
Hi Anatoly,
Good question
Nope, and that’s the problem. He compares two groups: one who does a bodybuilding style workout and other who does a powerlifting type. He then finds GH and testosterone being higher for the bodybuilding style and concludes that muscle growth is due to the acute hormone responses.
But the problem is that nobody is yet to prove that a bodybuilding style workout is better for a muscle growth than a power lifting type workout. People just assume that bodybuilders have more muscle than powerlifters which isn’t true. The campos study showed that both protocols produced surprisingly similar muscle growth.
I did a study which compared the two protocols for my thesis. But I couldn’t find a significant difference. I wish people didn’t drop out so much from the study.
Jim@TBF | Fri October 30, 2009
Well, we also remember how much tradition, and the physiology that was taught when many of the authors who write books currently went to school. Science develops rapidly and it is difficult for many in authority to concede to new findings when they have taught in another direction for so long.
Anoop | Thu November 12, 2009
Good point Jim.
It’s a fine line between being enthusiastic about your hypothesis and being unbiased and objective.
If you see someone too enthusiastic about their findings and can only say things to support their finding, you can suspect him to have a hard time “seeing” data which goes against. A good example is all those alternative healing proponents& fitness “gurus”.
Anoop | Mon November 16, 2009
Hi Amy,
I have moved your post to the forum. Check the forum and register and you can ask all the question you want.
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