Skeletal muscle act as a major organ of insulin-induced glucose metabolism. Additionally, muscle mass loss relates to insulin resistance (IR) and metabolic syndrome (Met-S). Skeletal muscle loss and intramuscular fat accumulation may lead to numerous pathologies triggered by multiple factors, including oxidative stress, inflammatory cytokines, mitochondrial dysfunction, IR, and inactivity. 

Sarcopenia, defined by a loss of muscle mass and a decline in muscle quality and function, is common in the elderly and is often seen in patients with acute or chronic muscle-wasting diseases. The association between Met-S and sarcopenia is now widely studied. Persistent inflammation, fat deposition, IR, vitamin D deficiency, etc. may play a complex role in the association between Met-S and sarcopenia. Met-S and sarcopenia worsen QOL and contribute to increased frailty, weakness, dependence, morbidity, and mortality. Patients with Met-S and sarcopenia simultaneously have a higher risk of several adverse health events than those with either Met-S or sarcopenia. There is also evidence to suggest that Met-S can be associated with sarcopenic obesity. 

Moderate exercise can improve Met-S and sarcopenia and may extend a healthy life span. However, there is insufficient evidence for pharmacological interventions for Met-S-associated sarcopenia, and further clinical data is needed to confirm these results.

Nishikawa H, Asai A, Fukunishi S, Nishiguchi S, Higuchi K. Metabolic Syndrome and Sarcopenia. Nutrients. 2021 Oct 7;13(10):3519. doi: 10.3390/nu13103519. PMID: 34684520; PMCID: PMC8541622.