Tehran University of Medical Sciences Journal of Nutritional Sciences and Dietetics 2 3 2017 08 01 61 61 EN Amir Shayganrad Science and Research Branch, Islamic Azad University, Tehran, Iran Nader Shakeri Department of sports physiology, Science and Research Branch, Islamic Azad University, Tehran, Iran Farshad Ghazalian Department of sports physiology, Science and Research Branch, Islamic Azad University, Tehran, Iran 2016 06 28 2017 08 01 Objectives: The aim of this study was to investigate the effect of branched-chain amino acids (BCAA) supplementation on lactate dehydrogenase, creatine kinase and total antioxidant capacity after a session of exhaustive strength exercise. Method: Twenty four men rock climbers aged 27 to 37 from Tehran province were randomly assigned to two groups of 12 subjects (amino acids, placebo). Five ml of blood was taken from all subjects in three stages: 30 post-exercise hours post-exercise. The subjects participated in a session of intense physical activity (70% repetition maximum resistance movements) and then the supplementation group received BCAA at the rate 6 g per day for 14 days. The placebo group received Maltodextrin capsules during this time. A day after completing the course, the subjects were once again present in the same location as the one in the pre-test and post-test was performed on all subjects. An independent t test at p < .05 was conducted to analyze the data. Results: The results showed that the use of BCAA has a significant impact on creatine kinase and lactate dehydrogenase before, immediately, and 24 hours post-exercise (p>0.05), but it has no significant impact on total antioxidant capacity (p<0.05). conclusion : According to the results, it can be said that BCAA may be useful in reducing the release of lactate dehydrogenase enzymes and creatine kinase. https://jnsd.tums.ac.ir/index.php/jnsd/article/view/61 https://jnsd.tums.ac.ir/index.php/jnsd/article/download/61/182