The interactions of sex, age, season, and habitual physical activity were examined in 41 male and 54 female Japanese age 65–83 yr, using a pedometer/accelerometer that determined step counts and amounts of physical activity (<3 and >3 metabolic equivalents [METs]) throughout each 24-hr period for an entire year. All 3 measures were greater in men than in women. In women, age was negatively correlated with step count and activity <3 METs, but in men, it was correlated with step count and activity >3 METs. Irrespective of sex or age, all 3 activity variables were low in the winter, peaking in spring or autumn. In the summer, step counts matched the annual average, but durations of activity <3 and >3 METs were, respectively, longer and shorter than in other seasons. These findings have practical implications for those promoting physical activity for older adults.
Yasunaga is with the Faculty of Liberal Arts and Sciences, Bunka Women’s University, Tokyo 187-0021 Japan. Togo, Watanabe, H. Park, S. Park, and Aoyagi are with the Exercise Sciences Research Group, Tokyo Metropolitan Institute of Gerontology, Tokyo 173-0015 Japan. Shephard is professor emeritus, Faculty of Physical Education and Health, University of Toronto, Toronto, ON, Canada.