The effect of weight Training in morning and evening on testosterone and cortisol in bodybuilders

The purpose of this study was to examine the effect comparison of weight Training at morning and evening shifts on Testosterone and cortisol in bodybuilders. 30 male students from Shahrood, Branch, Islamic Azad University were voluntary selected and randomly divided into the two groups; morning-time training group (N=15, weight = 74±2.69 kg, age = 22±2.18 years, length =172±3.37 training time = 10 am.) and evening-time training group (N=15, weight =77±4.15 kg, age = 21 ± 3.97 years, height =174±4.75 training time = 4 pm.). Both groups (Morning and afternoon) were performed resistance training program 3 days in week (12 weeks/36 sessions) with 50 to 80 % maximum power. Data was tested using dependent t test for comparison of data between pre- and posttest in per groups. Statistical significance was set at p<0.05. Also from the One Way ANOVA used for mean different comparing between post test in groups, and Tokay test for comparing between pre and post test mean different in per groups. The results showed there were significant differences between the amounts of testosterone (0.04) and cortisol (0.01) hormones secreted of both groups in pre-test and post-test. The findings of this research indicate that testosterone and cortisol hormones are influenced by the time of training which is due to circadian rhythm