Eating whey protein isolate helps build muscle in elderly people?
By David Liu
Sunday March 25, 2012 (foodconsumer.org) -- A new study released recently in British Journal of Nutrition suggests that eating whey protein isolate may help elderly men build muscle tissue, at least whey protein isolate ir better than casein protein.
The study led by Nicholas A. Burda of McMaster University in Canada and colleagues showed healthy elderly men who ate pure whey protein isolate had 65 percent increased myofibrillar protein synthesis in the rested leg, compared to those who ate pure isolated micellar casein.
The study was meant to determine the effect of eating pure isolated miceller casein or pure whey protein isolate on myofibrillar protein synthesis at rest and after resistance exercise in elderly men.
For the study, two groups of healthy elderly men with body mass index 26.4 kg/m2, with seven men in each group performed unilateral leg resistance exercise and were then assigned to use isonitrogenous quantities (20 grams) of casein or whey protein isolate. Then participants were measured for essential amino acids and leucine concentration.
Resistance exercise-stimulated rates of myofibrillar protein synthesis were also found to be greater after ingestion of whey protein isolate, compared to the ingestion of micellar casein.
The researchers concluded that "ingestion of isolated whey protein supports greater rates of MPS than micellar casein both at rest and after resistance exercise in healthy elderly men. This result is probably related to a greater hyperaminoacidaemia or leucinaemia with whey ingestion."
Hyperaminoacidaemia is a condition which sports nutrition companies claim supports muscle building. Whey protein isolate or whey protein powder is a key muscle building diet component or dietary supplement.