I feel a bit vindicated in one of my opinions. That’s because for years I’ve been asserting that ‘post-workout testosterone’ doesn’t really matter very much for bodybuilding. This has flown counter to what’s repeated, ad nauseum, by the bodybuilding community. They’ve been warning natural trainees within every book, report, and magazine article about the hormonal shortfalls and resulting muscle gain plateaus that will surely befall anyone who takes bodybuilding workouts past the one-hour time mark:
“Don’t stay in the gym more than one hour”, they’ll say. “Your testosterone will begin to drop and that’s not what you want for bodybuilding progress.”
But just a little common sense rejects this notion. The same geniuses who’ve been dispensing this advice have been simultaneously meting out information that’s not completely reconcilable with it: That “muscles don’t grow during workouts; they grow during rest between workouts.”
So again I ask: “Why should workout testosterone levels, or even ‘post-workout testosterone’ levels, matter if muscles are only growing during rest time in the days between workouts?”
The ‘post-workout testosterone’ crowd might counter this argument by claiming there’s a “window of opportunity” immediately following a workout in which we want endogenous testosterone to be high. During this window, the body gets a jump on recuperation by using post-workout testosterone and other raised hormone levels to kick-start protein synthesis. This has been so oft repeated that fitness gurus have apparently taken to merely saying it because they hear every other “expert” say it.
Now there’s evidence that casts serious doubt on the idea that ‘post workout testosterone’ is something of which to be concerned. The first of such evidence comes in the form of a study done on sex-based comparisons of post-workout myofibrillar protein synthesis (MPS). The study was done on eight men and eight women at McMaster University’s Kinesiology Department in Ontario Canada. The most surprising finding of this study was that post-workout stimulation of MPS was as pronounced in the women as it was in the men. This is significant given that women possess about 5 to 10 percent of the endogenous testosterone that men do.
‘Post Workout Testosterone’: Evidence that it matters
The idea that in-workout and ‘post workout testosterone’ are pivotal factors for muscle building progress isn’t without supporting evidence. A 2011 study done at the Norwegian School of Sports Sciences at Lillehammer University in Oslo, Norway showed that acute hormone boosts from training make a difference to strength gains. Researchers took twelve untrained male subjects and had them perform a four-workouts-per-week unilateral strength-training protocol for 11 weeks. The subjects each trained the arm muscles of one side of the body twice-per-week with a heavy leg training session preceding the arms-training bouts. They trained the arm muscles of the other sides of their bodies for two training sessions per week without the accompanying leg training. The respective side of each subject’s body that received arm workouts without the leg workouts was used as a ‘control group.’ By doing the study unilaterally like this, the researchers could ensure that the same nutritional variables were in play for both the experimental and control sides of the study. Acute hormonal responses and corresponding strength gains from the arm-training workouts were monitored and measured.
Serum growth hormone and testosterone levels increased significantly immediately following the training sessions in which legs were trained along with arms. This was in contrast to no significant hormonal changes occurring from the arms-only workouts. There was no substantial change in serum cortisol levels from either of the two types of training sessions.
The difference in arms strength gains between the experimental and control groups was noteworthy. There was a 21% increase in one-repetition-max biceps-curling strength of the arms/legs workout group. This is in contrast to a 14% increase in biceps-curling strength for the ‘arms only’ group. In addition, the arms/legs group had a greater increase in CSA (cross-sectional area) mass in the middle sections of the elbow flexors where the CSA of the flexors is largest.
The researchers also measured ‘peak power’ of biceps strength during the study. This was done by testing the biceps strength at both 30% and 60% of 1RM, respectively. Using this measurement, there were no statistical differences between the arms/legs training groups and the ‘arms only’ groups.
This study showed that the transient nature of ‘post workout testosterone’ and other acute hormone augmentation could make a difference to strength adaptation.
‘Post Workout Testosterone’: Evidence that it doesn’t matter
There’s recently been a rather thorough research study, however, resulting in evidence that ‘post workout testosterone’ spikes amount to not much more than an interesting blood-readout phenomena of a very transient nature. And it’s the transient nature of this spike that has to cause any thinking person a reason for pause. Think about it: Steroid users accelerate their muscle/strength gains by raising their testosterone levels six-fold above normal with either oral or intravenous use of those drugs. Not only is this amount of testosterone way above normal – it’s also jacking up the drug-users level of this hormone on a 24/7 basis while he or she is on the steroid cycle. Although the user’s subsequent bigger gains are direct evidence that higher testosterone levels can result in significant contractile tissue accretion – it might likewise be indirect evidence that such accretion can only be attained with levels and consistencies acquired by pharmacological means.
The study was conducted to test the effects of the natural testosterone spike. Researchers wondered if the post workout testosterone rise, along with upswings in other post-workout hormones, results in better adaptations to resistance training. They conducted it on 56 young men (a huge cohort) in order to obtain more accuracy than similar studies in the past. The subjects underwent a 12-week workout protocol of training 5 days per week on intense weight lifting with both upper and lower body exercises. Their lean body mass was measured. Their blood readings of testosterone, HGH, IGF-1, and cortisol were measured within the 120-minute post workout time window. Muscle biopsies were taken on the cross-sectional area of their vastus lateralus (thigh muscle) both before and at the finish of the study. The subject’s leg press strength was tested before and after the experiment. And of course, firm statistical analysis was applied to the compilation of all these findings.
What were the results of the study?
In a nutshell, ‘post workout testosterone’ spikes and other acute hormonal responses showed no significant association with gains in lean body mass or increases in leg pressing strength. Some of the subjects gained significant strength and mass, while some gained almost nothing, and many gained something of a mediocre amount. But what might be telling is the fact that the top 16% of gainers in strength and lean body mass showed no greater hormonal output than the bottom 16% of strength and muscle gain responders.
Interestingly, the researchers found a weak correlation between elevation of cortisol (along with HGH) and increases in CSA of Type 2 muscle fibers. This was especially counterintuitive considering that cortisol is known to be a catabolic hormone and HGH has collectively been shown in past studies to be more gluconeogenic and metabolism-modulating than anabolism-enhancing.
‘Post Workout Testosterone’ Studies… and why “bro science” carries weight
In light of the above-mentioned studies, there currently appears to be two opposing dispensers of information in the bodybuilding world. There are those who only practice bodybuilding and share their street-gained knowledge of it with others. In occasional antagonism to this, there are individuals within the vanguard of bodybuilding and strength training’s University research groups who label the former as propagators of mere “bro science” – as in “science” of such utter ‘junk’ variety that it originates and proliferates with about as much objectivity as is implied by the following revelatory sentence:
“Hey Bro, why don’t you try THIS to gain muscle… it worked for me.”
Understandably, there’s apparent disdain within the research community for the ongoing dissemination of bodybuilding and fitness information in the latter form. Research teams, with PhDs in biology, kinesiology and nutrition, etc., have legitimate reason to convey the impact and importance of their controlled research work above anecdotally-derived, individual discoveries that can mistakenly thought to be all-encompassing and conclusive.
What might be noted, however, is the present relative inconclusiveness from even the ‘scientific’ findings within bodybuilding and strength training. Take the above-cited studies on ‘post workout testosterone’ as example. Even the researchers of the third study – the most thorough of the three mentioned – admit in their summary that more research is needed before a complete understanding of exercise-induced, acute hormone elevations can be fully understood.
Where does that leave serious natural bodybuilders until the ‘science’ of this industry further unfolds?
It likely leaves them more legitimately relying on “bro science” by omission of un-contradictory scholarly knowledge than researchers within the industry care to realize.
1. Daniel W. D. West, Nicholas A. Burd, Tyler A. Churchward-Venne, Donny M. Camera, Cameron J. Mitchell, Steven K. Baker, John A. Hawley, Vernon G. Coffey, and Stuart M. Phillips. ‘Sex-based comparisons of myofibrillar protein synthesis after resistance exercise in the fed state’ (Journal of Applied Physiology, June 1, 2012, vol. 112, no. 11 1805-1813)
2. Ronnestad, B.R., Nygaard, H., Raastad, T. (2011) ‘Physiological elevation of endogenous hormones results in superior strength training adaptations.’ (European Journal of Applied Physiology, 111, 2249-2259)
3. Daniel W.D. West, Stuart M. Phillips. ‘Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training’ (European Journal of Applied Physiol. 2012 July; 112(7): 2693–2702.)