Milk Benefits Lean Body Mass

HAMILTON, OntarioMilk apparently does do a body good, as researchers from McMaster University found consuming fat-free milk after resistance exercise can increase lean mass accretion more than other post-exercise fuels. Their study, published in the American Journal of Clinical Nutrition (2007 Aug;86(2):373-81), compared consumption of dairy or soy protein or equivalent energy via carbs on training-induced lean muscle mass gain. A total of 56 young men trained five days a week for 12 weeks on a rotating split-body resistance program, as part of a parallel three-group longitudinal design. Immediately before and one hour after exercise the men consumed drinks of fat-free milk, fat-free soy protein, or maltodextrin; all the drinks were isoenergetically matched.

There were no differences seen in strength between groups. Type II muscle fiber area increased in all groups with training, but there were greater increases in the milk group compared to the soy or control groups. Milk and soy both increased Type I muscle fiber area compared to control, with men consuming milk showing greater increases. Fat- and bone-free mass (measured by dual-energy X-ray absorptiometry) increased in all groups, with the greatest increase in the milk group. The researchers concluded chronic consumption of milk after exercise promotes greater hypertrophy during early stages of resistance training compared with soy or carbohydrate consumption.