Project 459595

Periods of reduced physical activity (i.e., muscle disuse) caused by many clinical scenarios, such as hospitalization, a limb cast following a fracture, or joint replacement surgery, lead to a profound loss of muscle and strength. This loss of muscle and strength requires a prolonged and concerted effort to recover in rehabilitation and can often, especially in older persons, become a permanent loss in their function and ability to perform activities of daily living. Older adults who are weak after a muscle disuse period are at a greater risk of developing disability and transitioning to frailty and risk a loss of independence. Thus, a robust countermeasure to maintain muscle mass during the period of muscle disuse is needed. Adequate nutritional support has not been considered a frontline strategy to attenuate muscle loss during the muscle disuse period. However, we previously reported that a protein-based multi-ingredient supplement containing protein, creatine, vitamin D and fish oil effectively augmented muscle and strength in older adults. Here, we propose that the effects would extend to older people during a period of muscle disuse. Therefore, we aim to investigate whether this multi-ingredient supplement can reduce the loss of muscle and strength in older adults during muscle disuse, using a single-leg immobilization model. The results from this study will give us critical insights into mitigation of declines in muscle mass, which will helping older persons return to their activities of daily living after a period of muscle disuse. Our work has applications in several clinical scenarios, including joint replacement surgery.