Amino acids role in post-workout muscle growth

Two recent studies have sought to better understand how amino acids influence protein synthesis in exercisers. 

A study led by Stuart Phillips of McMaster University looked at whether a large single dose of whey protein (25g) had a different effect on post-exercise muscle protein synthesis than 10 smaller shots of 2.5g over a longer time period (a process designed to emulate the way in which another milk protein called casein is digested). A group of eight young male study subjects followed both dietary prescriptions after working out on the leg-extension machine.

The second study, led by Stefan Pasiakos of the US Army Research Institute of Environmental Medicine, also studied eight military personnel (seven men and one woman) who ingested a high-protein beverage (10g as essential amino acids) which contained either 1.87 or 3.5g leucine while working out on an indoor cycle.

In the first study, the single large dose of protein was found to increase muscle protein synthesis more than the series of smaller doses, and in the second study the synthesis was 33% greater among study participants who consumed the higher-leucine drink.

American Society for Nutrition spokesperson Shelley McGuire, PhD, said, “These studies, and others like them, help us understand and apply something we all inherently know: the human body works in a complex, yet completely logical way! It makes good sense that consuming a food containing high-quality protein (like milk) during and/or immediately following exercise would help muscles get stronger. Muscle strength doesn't just happen on its own – our muscles need to be both encouraged (as happens via exercise) and nourished (as happens when we eat well). Now we have even more scientific proof for this common-sense concept.”

Source: The American Journal of Clinical Nutrition

‹ Back