Habitual Protein Intake and Muscle Protein Synthesis

Protein intake stimulates muscle protein synthesis. From the standpoint of maintaining skeletal muscle mass with aging, it is important to optimize the adaptive response to food intake. However, a paucity of information is available describing the effects of habitual dietary protein intake (i.e. either high or low amounts of dietary protein consumed on a regular basis), on the subsequent meal-induced stimulation of muscle protein synthesis. An adaptation to a diet of several days or weeks may involve splanchnic and/or skeletal muscle adaptations that may further enhance, or decrease, the amino acid sensitivity of muscle protein synthesis after protein ingestion. The aim of this study is to investigate the effect of a habitual (14 days) high protein diet when compared with low protein diet on digestion and absorption kinetics and the subsequent muscle protein synthetic response to dietary protein ingestion.