Abstract
BACKGROUND: Sarcopenia is characterized by the progressive loss of muscle mass and function and is associated with an increased risk of fractures, disability, and mortality. Previous studies have explored the relationship between sarcopenia and physical function in community-dwelling older adults; however, limited research has focused on individuals requiring support or long-term care in populations where the effect of sarcopenia may be more severe. Therefore, the aim of this study was to investigate the factors associated with walking speed in older adults with and without sarcopenia living in long-term care facilities. METHODS: This cross-sectional study included 47 older adults (aged ≥ 65 years) who attended daycare facilities in Shiga, Japan. Participants were categorized into sarcopenia and non-sarcopenia groups based on the 2019 criteria of the Asian Working Group for Sarcopenia (AWGS). Physical function was assessed using respiratory muscle strength (maximum inspiratory pressure (PImax) and maximum expiratory pressure (PEmax)), grip strength, walking speed (six-meter walk test), and dynamic balance (maximum distance in the two-step test (MDST)). Pearson's correlation coefficient and stepwise multiple regression analyses were used to examine the association between walking speed and physical functional parameters. RESULTS: Walking speed significantly correlated with PEmax (r = 0.569, p = 0.002), grip strength (r = 0.500, p = 0.008), and MDST (r = 0.716, p < 0.001) in the non-sarcopenia group. PEmax (β = 0.387, p = 0.017) and MDST (β = 0.600, p < 0.001) were significant predictors of walking speed, explaining 60.6% of its variance (adjusted R² = 0.606). However, no significant associations or predictive variables were observed in the sarcopenia group, likely because of advanced muscle deterioration and confounding factors, such as comorbidities. CONCLUSIONS: Walking speed in older adults without sarcopenia was significantly associated with respiratory muscle strength and dynamic balance, suggesting that targeted interventions such as respiratory muscle training and balance exercises may help maintain or enhance mobility. Older adults with sarcopenia may require comprehensive interventions, including nutritional support and generalized muscle strengthening.