Postexercise Dietary Protein Strategies to Maximize Skeletal Muscle Repair and Remodeling in Masters Endurance Athletes: A Review.

Thomas M. Doering, Peter R. Reaburn, Stuart M. Phillips, David G. Jenkins

Participation rates of masters athletes in endurance events such as long distance triathlon and running continue to increase. Given the physical and metabolic demands of endurance training, recovery practices influence the quality of successive training sessions, and consequently, adaptations to training. Following muscle-damaging endurance exercise, research suggests masters athletes experience slower recovery rates in comparison to younger similarly-trained athletes. Given these discrepancies in recovery rates are not observed following non-muscle-damaging exercise, it is suggested that masters athletes have impairments of the protein remodeling mechanisms within skeletal muscle. The importance of post-exercise protein feeding for endurance athletes is being increasingly acknowledged, and its role in creating a positive net muscle protein balance post-exercise well known. The potential benefits of post-exercise protein feeding include elevating muscle protein synthesis and satellite cell activity for muscle repair and remodeling, as well as facilitating muscle glycogen resynthesis. Despite extensive investigation into age-related anabolic resistance in sedentary aging populations, little is known about how anabolic resistance affects post-exercise muscle protein synthesis, and thus muscle remodeling in aging athletes. Despite evidence to suggest physical training can attenuate, but not eliminate age-related anabolic resistance, masters athletes are currently recommended to consume the same post-exercise dietary protein dose (~20 g or 0.25 g/kg/meal) as younger athletes. Given the slower recovery rates of masters athletes following muscle-damaging exercise, which may be due to impaired muscle remodeling mechanisms, masters athletes may benefit from higher doses of post-exercise dietary protein, with particular attention directed to the leucine content of the post-exercise bolus.