Would not recommend this under any circumstances. If your doing legs, your doing legs, you should not have enough energy to do anything but legs other wise your not training to your full potential. By doing this your losing out on the necessary stimulation of these very large muscle groups (quads, hams, glutes, etc.). You are also cutting down on your ability, due to overall fatigue, to train your biceps to their max potential. Supersets generally refer to the sequencing of agonist or antagonist focused exercise, legs and biceps are completely different and have no agonist or antagonist action. Also, the same muscle group can be trained from a different angle, in a superset. For example, cambered bar skull crushers and rope pushdowns done in sequence.
"Testosterone concentrations have been shown to increase AFTER an acute bout of resistance or endurance exercise.
In response to prolonged endurance exercise (e.g., a marathon), testosterone levels will typically decline. Others have reported no change in testosterone after resistance exercise (Tremblay, Copeland & Van Helder, 2003)."
Generally testosterone increases will not occur during a bout of exercise but will be observed once the exercised has ceased. In fact an increase in the production of cortisol a catabolic hormone, will be observed during the exercise bout in response to the training especially during a day as stressful on the body as legs. The post anaerobic exercise spike in testosterone will come as the body begins its repair (anabolism/protein synthesis) on whatever muscle group was trained.
Tremblay, M., Copeland, J., & Van Helder, W. (2003). Effect of training status and exercise mode on endogenous steriod hormones in men. Journal of Applied Physiology, Retrieved from ww w . jappl.or g/ content /96/2/531.full
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