The purpose of this study was to determine the effect of one period of Zinc, Magnesium and vitamin B6 supplementation on testosterone and cortisol concentrations and ratio of testosterone to cortisol and performance in weight lifters. To this end, 12 weightlifters were selected among weightlifters of Kamyaran city and after completing questionnaire, were randomly divided into two groups: ZMA group (n=6; age: 18.76±2.39 year; height: 171.00±7.64 cm; weight: 74.36±10.01 kg) and placebo group (using dextrose) (n=6; age: 20.17±2.13 year; height: 171.66±3.77 cm; weight: 78.39±9.37 kg). Both groups were trained for 7 weeks (preparatory season training for weightlifters) 6 days per week and all had the same condition. Double-blind procedure was performed. Fasting blood samples 6 cc of the antecubital vein in the sitting position of subjects before and after completion of the course and in the same were collected. To measure total testosterone, free testosterone and cortisol, ELISA method was used. Vertical jump and long jump tests, medicine ball push test, squats test and military presses test were used to assess subject’s performance. Data' analysis was done using student t-test particularly dependent and independent groups; also, significance level was set to be p≤0.05. Results: no significant differences in the rate of total testosterone (p=0.695), free testosterone (p=0.379), cortisol (p=0.346) and ratio of testosterone to cortisol (p=0.718) and strength in both groups were improved. Conclusion: it seems that athletes to obtain more advantages in this field of sport do not need to use this supplements.
