Background: Several studies have reported an age-related decline of physical activity (PA). We examined the impact of 4 important transitional periods-adolescence, the beginning of postsecondary education, entry into the labor market, and parenthood-on the PA of participants in the Trois-Rivières quasi-experimental study.
Methods: In 2008, 44 women and 42 men aged 44.0 ± 1.2 years were given a semistructured interview; the frequency and duration of physical activities were examined during each of these transition periods. Subjects had been assigned to either an experimental program [5 h of weekly physical education (PE) from Grades 1 to 6] or the standard curriculum (40 min of weekly PE) throughout primary school.
Results: The percentage of individuals undertaking ≥ 5 h of PA per week decreased from 70.4% to 17.0% between adolescence and midlife. The largest decline occurred on entering the labor market (from 55.9% to 23.4%). At midlife, there were no significant differences of PA level between experimental and control groups. Men were more active than women at each transition except for parenthood.
Conclusions: Our results highlight a progressive nonlinear decline of PA involvement in both groups. Promotion initiatives should target these periods to prevent the decline of PA.