Our findings indicate that the participants of an 18 week intensive endurance exercise training program experienced significant (p < 0.001) reductions in resting testosterone (-25 to -45% decrease from pre-training), with some reaching the clinical criteria for androgen deficiency during the training regimen. Nonetheless, none of the participants displayed any running performance decrement, in fact, the opposite occurred (+18.6% improvement; p < 0.05). These preliminary findings suggest acute decreases in testosterone in and of itself may not be entirely indicative of a compromised exercise performance potential although elements of reproductive and bone health may still be compromised.
Keywords: Hypogonadism; androgen deficiency; exercise; men; stress.