Association Between Participation in Group-Based Exercise During Adolescence and Physical Activity in Older Age

OBJECTIVE: This study examined whether adolescent group-based exercise is associated with walking time and sports group participation in older age and explored sensitive period and accumulation models. METHODS: Cross-sectional data were drawn from the 2016 Japan Gerontological Evaluation Study, including 19,249 community-dwelling individuals aged ≥ 65. Group-based exercise was retrospectively assessed and defined using 3 approaches. First, exposure was participation at ages 13-18. Second, to isolate adolescent participation, we included only those active at ages 13-18. Third, an accumulation score was calculated by summing participation across 5 periods. Outcomes included walking ≥30 minutes per day and weekly sports group participation. Adjusted prevalence ratios were estimated using modified Poisson regression. Stratified analyses were conducted by sex and adolescent living standard. RESULTS: Adolescent group-based exercise was associated with walking ≥30 minutes per day (prevalence ratio: 1.04; 95% CI, 1.02-1.06) and weekly sports group participation (1.18; 95% CI, 1.11-1.25) in older age; associations were consistent across sex and adolescent living standard. Individuals who exercised only during adolescence still had higher activity levels in later life, supporting the sensitive period model. A greater number of life stages with participation was associated with higher later-life activity, supporting accumulation. CONCLUSION: Participating in group-based exercise during adolescence is associated with greater walking time and sports group participation in later life. Both adolescent exposure and cumulative engagement contribute to this association. Promoting equitable access to organized sports during adolescence and ensuring opportunities for organized physical activity across life stages may support greater walking time and sports group participation in older age.