Effects of Branched Chain Amino Acids on Soreness and Power Recovery Following an Eccentric Exercise Bout in Resistance Trained and Non-resistance Trained Males

Abstract

Previous studies have reported untrained individuals supplementing with branched-chain amino acids (BCAA) attenuates muscle soreness and improves recovery from eccentric exercise. However, there is current evidence suggesting trained individuals do not respond to protein supplementation in the same manner as untrained individuals. The purpose of the current study was to determine if BCAA ingestion following an acute bout of eccentric exercise could attenuate muscle soreness and improve recovery similarly between resistance-trained and untrained males. Fourteen trained males and twenty untrained males were randomly assigned to either a BCAA supplement group or a placebo. Lower body power output and perceived muscle soreness measures were taken for each subject before an eccentric exercise bout consisting of 5 sets of 8 repetitions on both leg extension and leg flexion. The same measures were assessed immediately after the eccentric exercise bout, 24 hours after, 48 hours after, and 72 hours after the eccentric exercise bout. All groups experienced an increase in perceived muscle soreness following the eccentric exercise bout. However, no statistical differences were found between or within any of the four groups (p > 0.05). For peak power, there was no significant interaction or main effects for time (p > 0.05) or group (p > 0.05). For average power, there was no significant interaction or main effects for time (p > 0.05); however there was a main effect for group (p < 0.05). These results indicated that the untrained group receiving the BCAA supplement had a significantly higher overall average power output than the untrained group receiving the placebo when time was not a variable.