Abstract des Autors

This study examined the effects of equal anaerobic and aerobic total work outputs on the relationship between reproductive hormones in men. Nine subjects performed three randomized trials on separate days: 1) 1 h period of rest (control), 2) 1 h continuous arobic exercise (65% VO2max), and 3) 1 h intermittent anaerobic exercise (which included 2 min exercise periods at 110% VO2max). The total work output of the aerobic and anaeribic trials were equated. For the 8 h after each experimental trial, blood samples were collected hourly and analysed for testosterone, luteinizing hormone (LH), follicle-stimulatin hormone (FSH), prolactin and cortisol. Diet, physical activity and circadian influences were all controlled. Compared with the control, the aerobic and anaerobic trils significantly elevated testosterone, prolactin and cortisol; however, these changes were transient and returned to control levels within 1-2 h of revovery. Neither exercise produced significant changes from control for LH and FSH. The area under the hormonal response curves (AUC) was calculated for the 8-h recovery period. The testosterone and LH AUC for the aerobic and anaerobic trials were greater than the control trial. The conrtisol AUC for the anaerobic trial was greater than both the control and aerobic trials, but the aerobic and control trials did not differ from one another. Correlation analysis among the AUC results within each trial showed testosterone and LH to be significantly related during the control (r = 0.723, P < 0.05) and aerobic (r = 0.801, P < 0.01) tirals, but not so during the anaerobic trial (r = 0.430, P > 0.05). No other significant correlations were found. The present findings suggest the relationship between testosterone and LH is affected by anaerobic exercise but not aerobic exercise. However, the effect of anaerobic exercise upon the testosterone-LH relationship did not seem related to the concurrently induced prolactin or cortisol changes. Anaerobic exercise may produce some degree of temporary alteration within the testosterone-LH component of the hypothalamic-pituitary-gonadal axis; however, the meahcnism for this phenomenon reaims unclear. Verf.-Referat