Physical Activity Levels Among Elderly Residents in Small Remote Islands in Japan

This study quantified the physical activity of older residents of two small remote Japanese islands and identified associated factors. A questionnaire survey and accelerometer measurements collected data from 79 participants aged ≥ 65 years on Kabashima and Hisakajima Islands in May-June 2024. The median daily step count was 4555, similar to or higher than national averages. Significant associations were found between physical activity levels and age, living alone, car ownership, frequency of going out, and self-rated health. The smallest community had the highest median step count. There was substantial day-to-day variation in individual activity levels. Despite lacking environmental factors that earlier studies have identified as promoting physical activity, the residents' activity levels were higher than mainland averages, suggesting that relationships between neighborhood environment and physical activity are dependent on the context of populations. Possible explanations for the physical activity of our study participants include health-conscious behaviors of older islanders, unique environmental factors on small islands promoting activity, self-selection to live in an environment that requires physical activity, selection bias toward more active individuals, or the possibility that only those who are able to maintain island residence currently live there. Further longer-term research should examine intra-individual variation and elucidate factors influencing physical activity on small remote islands.