Ramin Dadkhah - Master of Sports Physiology, Department of Sports Physiology, Faculty of Physical Education, Islamic Azad University, Islamshahr Branch, Islamshahr, Iran.
Yaser Kazemzadeh - Assistant Professor, Department of Sports Physiology, Faculty of Physical Education, Islamic Azad University, Islamshahr Branch, Islamshahr, Iran.
Saeed Sedaghati - Assistant Professor, Department of Sports Management, Faculty of Physical Education, Islamic Azad University, Islamshahr Branch, Islamshahr, Iran.

Introduction: Improving adaptive responses to exercise through dietary interventions, especially sports supplements, has been considered. The aim of the present study was to compare the effect of Leucine and L-arginine supplementation before and after resistance training on athletes' protein catabolism indices during Ramadan. Methods: In this study, ۴۰ male bodybuilders were selected and randomly divided into four groups of resistance training (n=۱۰) and resistance training group and Leucine supplementation (n=۱۰), resistance training group and L-arginine supplementation (n=۱۰) and the control group (n=۱۰). Leucine and L-arginine tablets were poured as powder into ۱g empty capsules and placebo was in the form of ۱g capsules, the same shape, size and color of ۱g Leucine and L-arginine tablets. The amount of supplements was ۰.۱g per kg of body weight. The training protocol of the two training groups was performed for eight weeks in three sessions per week.To analyze the data, the statistical method of analysis of covariance was used and to determine the differences between the groups, Bonferroni post hoc test and at a significant level in all tests, P≤۰.۰۵ was considered. Results: Statistical analysis did not show a significant difference between groups in uric acid variable (p=۰.۰۹۷). Also, the results showed that resistance training significantly decreased urea (p=۰.۰۰۱), creatinine (p=۰.۰۰۱) and increased hypoxanthine (p=۰.۰۰۰) and xanthine oxidase (p=۰.۰۰۰). Resistance training with Leucine and L-arginine supplementation increased there was a significant urea, creatinine and a significant decrease in hypoxanthine and xanthine oxidase compared to the resistance training group. There was a significant difference between the two groups of supplements only in the amount of xanthine oxidase. In the resistance training group and Leucine supplementation, the amount of xanthine oxidase was significantly greater than in the resistance training group and L-arginine supplementation. Conclusion: Finally,resistance training with Leucine and L-arginine supplementation in fasting athletes could provide a platform for reducing protein catabolism due to exercise and it can be said that coaches and athletes to reduce catabolism due to exercise. During Ramadan, they can take Leucine and L-arginine supplements to increase performance and reduce damage.

Leucine, L-arginine, Resistance training, Protein catabolism, fasting