A hallmark of aging is an impaired ability to adequately recover following a stressor, such as muscle disuse, resulting in muscle fibrosis and weakness thereby increasing the risk for falls and loss of independence. Mechanistic-based therapeutic strategies to enhance muscle recovery in older adults do not exist. Metformin has been implicated to have positive effects on muscle size and function through non-glycemic mechanisms. Metformin has been shown to enhance macrophage function and lessen cellular senescence burden by targeting SASP in a variety of muscle interstitial cells. However, the role of metformin to improve muscle recovery in older adults following disuse atrophy through immunomodulating and senomorphic mechanisms have not been examined. Therefore, the purpose of this study is to conduct a randomized, double blind, placebo-controlled clinical trial in older adult participants to determine if short-term metformin delivery (vs placebo) during the recovery phase following disuse atrophy can improve muscle regrowth.