maanantai 21. kesäkuuta 2010
BCAAs Boost Protein Synthesis in Muscles
STOCKHOLM, Sweden—Branched-chain amino acids (BCAAs) can increase the body’s skeletal muscle growth in combination with resistance exercise, according to a new study (Acta Physiol (Oxf). ePub 2010 May 28. DOI: 10.1111/j.1748-1708.2010.02151.x). Researchers from the Swedish School of Sport and Health Sciences sought to distinguish between the influence of resistance exercise and BCAA on key enzymes involved in the regulation of protein synthesis in skeletal muscle. Nine healthy adults received either a mixture of BCAAs or flavored water before performing unilateral resistance exercise on two separate occasions. Muscle biopsies were taken from both resting and exercising muscle before, immediately after and one hour after exercise.
Phosphorylation of the mammalian target of rapamycin (mTOR) pathway was enhanced in exercising and resting muscle to a greater degree with BCAA supplementation. Also, BCAA intake increased the phosphorylation of the enzyme p70(s6) kinase, compared to resistance exercise alone. Exercise alone and with BCAA supplementation attenuated phosphorylation of the eukaryotic elongation factor 2 (eEF2) in exercising and resting muscles.