Purpose: Branched-chain amino acid (BCAA) can boost anabolism through an increase in the internal concentration of BCAA, which leads to facilitating anabolic hormone release to stimulate the power of the muscles. Studies on administration of BCAA to minimize fatigue substances during long periods of high intensity exercise have been conducted. However, there are disagreements concerning the results of these studies.
Methods: A comprehensive search was performed on electronic databases up to November 2021 for trials evaluating the effects of BCAA on recovery following exercise. Mean ± standard deviation of follow-up cortisol, insulin, ammonia, and lactate concentrations were extracted to calculate the effect size for meta-analysis.
Results: A total of 146 participants for cortisol and 279 participants for lactate were found from the 7 and 15 studies, respectively. The results revealed a significant effect of BCAA supplementation on cortisol concentration during 120≤ min post exercise follow-up. Moreover, without considering follow-up times, an overall analysis showed that BCAA was effective in reducing blood lactate in aerobic exercise and the trained status of athletes.
Conclusions: The advantages of BCAA administration relate to a reduction in cortisol concentration after 2h and ameliorated muscle function because of a probable attenuation of fatigue substances immediately after exercise.