Aging has been associated with a reduced muscle protein synthetic response to protein intake, termed “anabolic resistance.” Physical activity performed before protein intake increases the use of protein-derived amino acids for postprandial muscle protein accretion in senescent muscle. Thus, the level of habitual physical activity may be fundamental to maintain the anabolic responsiveness to protein intake with aging.
We provide evidence to suggest that maintenance of physical activity can reduce the anabolic resistance of muscle protein synthesis to protein intake with aging.
Department of Human Movement Sciences, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands
Address for correspondence: Luc J.C. van Loon, Ph.D., Department of Human Movement Sciences, Maastricht University Medical Centre+, P.O. Box 616, 6200 MD Maastricht, The Netherlands (E-mail: L.vanLoon@maastrichtuniversity.nl).
Accepted for publication: November 15, 2012.
Associate Editor: Romain Meeusen, Ph.D., FACSM