Serum insulin was increased in both groups.
It is evident as to why insulin increased in the CHO group as 10 g of carbohydrate were ingested. In addition, the WP group also underwent a similar increase in insulin in the absence of ingested carbohydrate, which is in agreement with the insulin response previously demonstrated with 20 g of whey protein (10 g EAAs) . The Akt/mTOR signalling pathway is activated by insulin. Insulin binds with its receptor and leads to an increase in tyrosine phosphorylation of IRS-1 and eventually mTOR activation. In the present study, 17-AAG order insulin significantly increased in both groups 30 min post-supplement ingestion and 15 min post-exercise, which see more was mirrored by significant MAPK inhibitor increases in IRS-1 activation at 15 min post-exercise. Even though Akt phosphorylation was not significantly increased, activation of IRS-1 likely contributed to the observed increases in mTOR
activation; however, this activity was not preferentially contingent on 10 g of whey protein ingestion. mTOR is a 289 kDa serine/threonine kinase downstream of Akt and stimulates protein synthesis through downstream activation of p70S6K and 4E-BP1, providing a key point of convergence for both resistance exercise and amino acids . Amino acid ingestion has been shown to significantly enhance mTOR signalling [25, 50]. In the present study, the acute bouts of resistance exercise significantly increased mTOR about and p70S6K activation at 15 min post-exercise, while a marked decrease in 4E-BP1 activation was also observed at 15 min post-exercise. While we observed mTOR activation to be enhanced by resistance exercise, the Akt/mTOR pathway signalling intermediates we assessed were unaffected by the provision of 10 g of whey protein comprised of 5.25 g EAAs. Previous work has suggested that a minimal amount of 20 g is needed to stimulate MPS ; however, others have demonstrated positive effects utilizing a dosage as low as 6 g EAAs .
Increases in MPS following resistance exercise have been observed when utilizing 10 g of whey protein; however, the protein supplement was co-ingested with 21 g of carbohydrate . However, it has recently been shown that approximately 5 g (2.2 g EAAs) and 10 g (4.2 g EAAs) of whey protein without carbohydrate significantly increased MPS 37% and 56%, respectively, over baseline. In this study, it was also shown that 20 g (8.6 g EAAs) maximally stimulated MPS following resistance exercise . Although, our results are supported by previous data which demonstrated that 20 g of albumin protein (8.6 g EAAs) enhanced MPS after resistance exercise, yet had no effects on activation of the mTOR pathway intermediates, S6K1, rps6, and eIF2Bε post-exercise , the dosage used in the current study (10 g whey protein, 5.