DHEA Effects on Metabolism and Exercise Performance in Men

Abstract

1185 Dehydroepiandrosterone (DHEA) and DHEA-sulfate (DHEA-S), the most abundant steroid hormones in blood, are produced by the adrenals and serve as precursors for testosterone and estrogen. DHEA supplementation in persons over 60 yrs induces a variety of beneficial effects, but whether such effects occur in persons 20 to 45 yrs has not been examined. PURPOSE: To examine the effects of DHEA supplementation on metabolic parameters and exercise performance. METHODS: Male (n = 15) subjects, 34 ± 1 yrs, participated in a randomized, double-blinded crossover study where, after a maximal treadmill tests (VO2max) and baseline testing, participants received either DHEA (100mg/day) or Placebo (P) for a 4-week period. After a 3-week washout, the treatments were switched. Participants were tested under both conditions between weeks 2 and 4 of supplementation. Testing included two high-intensity treadmill tests (90% of VO2max) and a physical battery (pull-ups, handgrip strength and endurance, and step test while wearing a 22 kg weight belt). RESULTS: Baseline plasma DHEA-S concentrations were 4.8 ± 0.7 and 13.5 ± 1.5 μM and DHEA values were 16.2 ± 1.5 and 24.2 ± 2.6 nM, for P and DHEA, respectively. Despite signficant increases in plasma DHEA and DHEA-S, supplementation with DHEA had no effect on physical performance, peak exercise lactate, or basal testosterone (Table 1). In contrast, metabolic activity of DHEA supplementation was evidenced by a greater exercise-induced rise in blood glucose as compared to P. CONCLUSION: Although DHEA appears to exert metabolic actions, no significant performance or androgenic effects were noted in men 20 to 45 yrs. The lack of effect may be explained by normal DHEA/DHEA-S values, no increase in testosterone, and/or an insufficient time period for inducing performance-enhancing effects.Table 1: Comparison of DHEA and Placebo.