Skip to main content

Influence of supplementation with branched-chain amino acids in combination with resistance exercise on p70S6 kinase phosphorylation in resting and exercising human skeletal muscle

Buy Article:

$51.00 plus tax (Refund Policy)


Abstract Aim: 

Skeletal muscle growth is thought to be regulated by the mammalian target of rapamycin (mTOR) pathway, which can be activated by resistance exercise and branched-chain amino acids (BCAA). The major aim of the present study was to distinguish between the influence of resistance exercise and BCAA on key enzymes considered to be involved in the regulation of protein synthesis, including p70S6 kinase (p70S6k). Methods: 

Nine healthy subjects (four men and five women) performed unilateral resistance exercise on two occasions separated by 1 month. Subjects were randomly supplied either a mixture of BCAA or flavoured water. Muscle biopsies were taken from both resting and exercising muscle before, after and 1 h after exercise. Results: 

Phosphorylation of Akt was unaltered by either resistance exercise and/or BCAA supplementation whereas mTOR phosphorylation was enhanced (P < 0.05) to a similar extent in both exercising and resting muscle following exercise in the absence (70–90%) and presence of BCAA supplementation (80–130%). Phosphorylation of p70S6k was unaffected by resistance exercise alone; however, BCAA intake increased (P < 0.05) this phosphorylation in both legs following exercise. In resting muscle, a 5- and 16-fold increase in p70S6k was observed immediately after and 1 h after exercise, respectively, as compared to 11- and 30-fold increases in the exercising muscle. Phosphorylation of eukaryotic elongation factor 2 was attenuated 1 h after exercise (P < 0.05) in both resting (10–40%) and exercising muscle (30–50%) under both conditions. Conclusion: 

The present findings indicate that resistance exercise and BCAA exert both separate and combined effects on the p70S6k phosphorylation in an Akt-independent manner.

Keywords: mTOR; resistance exercise; translation initiation

Document Type: Research Article


Publication date: November 1, 2010


Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more
Real Time Web Analytics