Hormone Responses to Resistance vs. Endurance Exercise in Premenopausal Females

Sixteen, cross-trained, premenopausal women participated in an endurance, resistance, and control session to compare hormone responses. The resistance session included 3 sets of eight exercises at 10 RM intensity. The endurance session consisted of a 40-min cycling protocol at 75% of maximal heart rate. During the control session, subjects rested for 35 min. Serum DHEA, estradiol, testosterone, growth hormone, IGF-I, cortisol, and plasma lactate concentrations were measured pre-exercise, post-exercise, and 30 min into recovery. Differences in intensity variables existed between the three sessions. Endurance exercise elicited increases in growth hormone, estradiol, and testosterone compared to the control session, and growth hormone increased after the resistance compared to the control session. The exercise protocols used in this study indicate that an acute bout of exercise can stimulate the endocrine system in premenopausal females. In addition, these results indicate that differences exist between these two exercise protocols when compared to a control session. Key words: dehydroepiandrosterone, testosterone, estradiol, growth hormone, IGF-I