Effect of strength training session on plasma amino acid concentration following oral ingestion of leucine, BCAAs or glutamine in men

We examined the acute effects of a 1-h strength training session (STS) on plasma amino acid concentration following orally ingestion of leucine, branched-chain amino acids (BCAAs) or glutamine in nine physically active men who participated in double-blinded and randomised experiments. The subjects took placebo, leucine, BCAAs, or glutamine capsules (50 mg/kg) in either rest (REST) or STS condition. Blood samples were taken before and at 30, 60, 90, and 120 min after the beginning of the treatment and they were assayed for plasma amino acids with HPLC. Following both leucine and BCAA ingestion the peak concentration of leucine was similar at rest (524 ± 46 and 530 ± 29 nmol/ml, respectively) and similar after STS (398 ± 43 and 387 ± 46 nmol/ml, respectively) but the rest and STS concentrations differed from each other ( P