Mechanisms responsible for disuse muscle atrophy: Potential role of protein provision and exercise as countermeasures

Muscle disuse is often observed after injury or during periods of illness, resulting in the loss of muscle mass and strength, with sometimes debilitating consequences. Although substantial advancements have been made in determining the mechanisms responsible for the etiology of muscle disuse atrophy in rodents, only in recent years have studies of any significant number focused on reaffirming these findings in humans. In this review, we discuss the processes responsible for disuse atrophy as based on current evidence and highlight where gaps in our knowledge persist. Furthermore, given the emphasis placed on resistance exercise and nutrition as potential therapeutic countermeasures, we consider recent advancements in the study of resistance exercise and nutrition in the stimulation of muscle protein synthesis and the associated implications when devising effective treatment strategies. (C) 2013 Elsevier Inc. All rights reserved.