Abstract
OBJECTIVES: This study aimed to explore the independent and joint associations of daily sitting time and leisure-time physical activity (LTPA) with sarcopenia among older adults. METHODS: The participants were 847 community-dwelling adults aged 60 or older from Beijing and Shanghai, China. Sarcopenia was diagnosed based on the criteria established by the Asian Working Group for Sarcopenia (2019). Daily sitting time and LTPA were self-reported using the Physical Activity Scale for the Elderly (PASE). Logistics regression models were used to explore the associations between daily sitting time, LTPA, and sarcopenia. To examine joint associations, participants were classified based on daily sitting time and LTPA levels. Final models were adjusted for sociodemographic variables, lifestyle factors, and chronic conditions. RESULTS: Prolonged sitting time and insufficient LTPA were independently associated with higher odds of sarcopenia. Among insufficiently active participants, sitting for 1-2 h, 2-4 h, and more than 4 h per day was associated with 5.52-fold (95% CI: 1.13-26.83), 6.69-fold (95% CI: 1.33-33.59), and 12.82-fold (95% CI: 2.75-59.85) increased odds of sarcopenia, respectively, compared to sitting for less than 1 h. For those meeting the physical activity guideline (≥150 min of LTPA per week), only sitting for more than 4 h per day was significantly associated with higher odds of sarcopenia (OR: 7.25, 95% CI: 1.99-26.36). CONCLUSIONS: Prolonged sedentary behavior was associated with increased odds of sarcopenia. The higher odds of sarcopenia associated with more than 4 h daily sitting may not be offset by achieving the recommended levels of physical activity.