Longitudinal Changes in Moderate to Vigorous Physical Activity in Community-Dwelling Older Men and Women: A 2-Year Prospective Cohort Study in Japan

Background: To examine longitudinal changes in accelerometer-measured moderate to vigorous physical activity (MVPA) and associated factors of changes in MVPA among community-dwelling older Japanese men and women over 2 years of follow-up. Methods: In total, 601 participants (72.2 [5.4] y, 40.6% men) were included. MVPA was assessed at baseline (2011) and follow-up (2013) using triaxial accelerometers. Sex-stratified multiple linear regression models were used to identify associated factors of changes in MVPA. Results: On average, a significant decrease in MVPA over 2 years was observed only in women (P < .001). Higher baseline MVPA levels and older age were significantly associated with a decrease in MVPA over 2 years in both men and women. Men who were currently drinking (vs no) and had faster maximum gait speed showed statistically significant increases in MVPA. Women who had very poor/poor economic status (vs fair/good) and were socially isolated (vs no) showed statistically significant increases in MVPA over 2 years, while those who had fear of falling (vs no) and poor/fair self-rated health (vs good/ very good) showed statistically significant decreases in MVPA over 2 years. Conclusions: Our findings showed different associated factors of changes in MVPA by sex, suggesting the importance of accounting for sex differences in terms of developing specific intervention strategies for promoting MVPA among older men and women.