|Studies show that "women demonstrate significantly larger satellite cell and satellite cell nucleus areas than men" (Roth. 2000) - an effect that could be mediated by the effects of estrogen, not testosterone on satellite cells.|
To make a long story short: Without satellite cells, your muscle repair and growth will be impaired, which is why the results Thue Kvorning and Danish colleagues present in a soon-to-be-published paper in Acta Physiologica are relevant for everyone who want to gain or simply maintain maximal / optimal muscle mass.
In the corresponding experiment, the Danish researchers treated 22 moderately trained young men with a GnHR analogue called goserelin that will dock to the gonadotropin receptors in the brain without stimulating the production of testosterone.
|Figure 1: Graphical overview of the procedures (Kvorning. 2014)|
|In obese boys whey + cho shakes lead to sign. T-reductions (Schwartz. 2014)|
Don't ask me what exactly it is that causes this effect, but I suspect it may be related to the huge insulin spike (+410% - no typo!) the subjects experienced. From studies in women with polycystic ovary syndrome we know that insulin which will usually augment the release of sex hormones loses its function in vivo (Willis. 1996).
A similar temporary suppression of the pulsatile luteinizing hormone release and subsequent acute redutions in testosterone has been observed in adults in response to glucose alone (Iranmanesh. 2012). No reason to avoid carbs, though. In a study by Volek et al. the consumption of a high fat diet lead to a persistent 22% and 23% reduction in total and free testosterone (Volek. 2001).
"A standardized warm-up was performed before training consisting of 4 sets of squats with 20 repetitions without load and with 1 min rest between sets. Subjects from both groups trained using the same progressive strength training program. The programs were performed 3 times a week for 8 weeks and consisted of leg press, knee extension, leg curl, bench press, lat pull down, biceps curl, and elbow extension. Subjects did 4 sets of each exercise for the lower body and 3 sets of each exercise for the upper body. The strength training period consisted of 24 training sessions periodized in 3 cycles of 8 training sessions with changing training loads (6 RM – 10 RM). The goserelin group and the placebo group increased training loads to the same extent and underwent the same training volume." (Kvorning. 2014)In contrast to the training stimulus, which was identical for both groups, the intra-muscular response to the workout differed significantly between the young men in the goserelin group (10-20x reduced testosterone levels) and their peers in the placebo group:
|Figure 2: This is one of the cases, where having more is not better. Having more free satellite cells and fewer myonuclei is certainly not a good thing for someone striving to build maximal muscle mass.|
In view of the resistance training focus of the workouts, it's not really surprising that on such changes were observed in the slow-twitch, endurance-type type I fibers in either group.
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