Post-exercise whey protein hydrolysate supplementation induces a greater increase in muscle protein synthesis than its constituent amino acid content

Abstract

It is well known that ingestion of a protein source is effective in stimulating muscle protein synthesis after exercise. In addition, there are numerous reports on the impact of leucine and leucine-rich whey protein on muscle protein synthesis and mammalian target of rapamycin (mTOR) signalling. However, there is only limited information on the effects of whey protein hydrolysates (WPH) on muscle protein synthesis and mTOR signalling. The aim of the present study was to compare the effects of WPH and amino acids on muscle protein synthesis and the initiation of translation in skeletal muscle during the post-exercise phase. Male Sprague -Dawley rats swam for 2 h to depress muscle protein synthesis. Immediately after exercise, the animals were administered either carbohydrate (CHO), CHO plus an amino acid mixture (AA) or CHO plus WPH. At 1 h after exercise, the supplements containing whey-based protein (AA and WPH) caused a significant increase in the fractional rate of protein synthesis (FSR) compared with CHO. WPH also caused a significant increase in FSR compared with AA. Post-exercise ingestion of WPH caused a significant increase in the phosphorylation of mTOR levels compared with AA or CHO. In addition, WPH caused greater phosphorylation of ribosomal protein S6 kinase and eukaryotic initiation factor 4E-binding protein 1 than AA and CHO. In contrast, there was no difference in plasma amino acid levels following supplementation with either AA or WPH. These results indicate that WPH may include active components that are superior to amino acids for stimulating muscle protein synthesis and initiating translation.

Effects of resistance training associated with whey protein supplementation on liver and kidney biomarkers in rats

“…After exercise, the supplement containing wheybased protein promotes a significant increase in the fractional rate of protein synthesis and phosphorylation of the mammalian target of rapamycin (mTOR) levels. Higher amino acid utilization in muscular protein synthesis determinates a lower amino acid hepatic metabolization (Kanda et al 2013). This physiologic mechanism suggests that WP supplementation when associated with RT does not promote hepatic overload.…”

Quantitation of underivatized branched-chain amino acids in sport nutritional supplements by capillary electrophoresis with direct or indirect UV absorbance detection

“…The total amount of BCAAs was at 194.2 and 199.6 mg/g in vanilla and chocolate type. In high quality whey protein, the content of BCAAs was reported around at 209 mg/g [27]. The obtained data seemed to match with the nutritional value since such two sports nutritional supplements were made from whey protein.…”

Pre-exercise casein peptide supplementation enhances endurance training-induced mitochondrial enzyme activity in slow twitch muscle, but not fast twitch muscle of high fat diet-fed mice

“…These results suggest that casein peptide supplementation is effective even in small quantities combined with exercise. Additionally, a previous study demonstrated that post-exercise whey protein hydrolysate supplementation increased muscle protein synthesis compared with ingestion of its constituent amino acids in a rat model 18) . Therefore, it was suggested that the peptide (protein hydrolysate) has bioactive functions, and that peptide ingestion might be more effective than amino acid supplementation.…”