Effect of Strength Training and Concurrent Strength and Endurance Training on Strength, Testosterone, and Cortisol

Abstract

Eleven subjects (6 M, 5 F) strength trained 3 times a week for 16 weeks, and 22 subjects (14 M, 8 F) did likewise while also performing endurance training 3 times a week on alternate days. All variables were tested every 4 weeks for 16 weeks. Significant gender differences were observed for bilateral incline leg press and bench press 1-RM, serum testosterone (T), urinary free cortisol (UC), ventilation threshold (VT), and O₂ max. There was a significant increase in bilateral incline leg press and bench press 1-RM for both training groups and genders. Relative gains in bilateral incline leg press and bench press 1-RM were similar for men. For women the gains in bilateral incline leg press 1-RM, but not bench press, were lower with concurrent training than with strength training only. No significant differences in T were observed with either program. UC was significantly elevated at 8 weeks for men and remained so after concurrent training, but decreased to baseline levels after strength training. UC decreased in the strength training women at 8 weeks but increased for women in both groups at 16 weeks. VT and O₂ max increased at 16 weeks of concurrent training. This indicates there are differences in strength and hormonal adaptations between men and women with concurrent training and strength training only.