Frailty, an age-related state of low physiological reserve and high vulnerability to stressors, impacts on health, functional independence, quality of life and survival; its early detection at the prefrailty stage offers the opportunity for preventive intervention. Sarcopenia, a hallmark of frailty, may occur in association with obesity and worsen functional deterioration. Obesity is strongly associated with insulin resistance and is a risk factor for both cardiometabolic diseases and cognitive impairment. Adipose tissue exerts autocrine and paracrine functions leading to chronic low-grade inflammation and increased oxidative stress that, in turn, decrease muscle density and precipitate muscle strength loss. Sleep disturbances and sarcopenia might be causally related through dysregulation of glucose metabolism and disruption of the secretory pattern of hormones involved in muscle metabolism.