Associations between sarcopenia operationalized using muscle strength or power and health-related parameters

Background and objectives: The present study examined the associations between sarcopenia, operationalized through muscle strength or muscle power, and health parameters in Italian community-dwelling older adults. Design: Cross-sectional study. Setting: Unconventional settings across Italy. Participants: Italian older adults (65+ years) who provided a written informed consent. Measurements: Physical function was evaluated according to isometric handgrip strength (IHG) and 5-time sit-to-stand (5STS) performances. Muscle power parameters were estimated based on 5STS values. Sarcopenia was operationalized according to the presence of low physical function (i.e., IHG or 5STS), or low muscle power, plus low appendicular skeletal muscle mass. Health parameters included the capacity to perform the 400 m test, adherence to the Mediterranean (MED) diet, practice of physical activity (PA), blood pressure (BP) values, blood concentration of total cholesterol and glucose, verbal fluency, sleep quality, and self-reported health status. Results: Results indicated that sarcopenic indexes had a poor-to-moderate level of agreement. Moreover, results indicated that operationalizing sarcopenia using muscle power measures provided exclusive or stronger associations with health parameters. Specifically, older adults classified as sarcopenic based on muscle power values were less likely to complete the 400-meter walk test, more likely to engage in PA, reported poorer self-rated health, and showed lower adherence to the MED diet. Conclusions: Findings of the present study indicated that sarcopenia indexes based on muscle strength or muscle power capture different aspects of older adults' health. Specifically, operationalizing sarcopenia using muscle power measures provided exclusive or stronger associations with health parameters.