Purpose: The purpose of this study was to identify the factors explaining regular physical activity among Canadian adolescents.
Design: A cohort study conducted over a period of 2 years.
Setting: A French-language high school located near Québec City.
Subjects: A cohort of 740 students (352 girls; 388 boys) aged 13.3 +/- 1.0 years at baseline.
Measures: Psychosocial, life context, profile, and sociodemographic variables were assessed at baseline and 1 and 2 years after baseline. Exercising almost every day during leisure time at each measurement time was the dependent variable.
Results: The Generalized Estimating Equations (GEE) analysis indicated that exercising almost every day was significantly associated with a high intention to exercise (odds ratio [OR]: 8.33, confidence interval [CI] 95%: 5.26, 13.18), being satisfied with the activity practiced (OR: 2.07, CI 95%: 1.27, 3.38), perceived descriptive norm (OR: 1.82, CI 95%: 1.41, 2.35), being a boy (OR: 1.83, CI 95%: 1.37, 2.46), practicing "competitive" activities (OR: 1.80, CI 95%: 1.37, 2.36), eating a healthy breakfast (OR: 1.68, CI 95%: 1.09, 2.60), and normative beliefs (OR: 1.48, CI 95%: 1.14, 1.90). Specific GEE analysis for gender indicated slight but significant differences.
Conclusions: This study provides evidence for the need to design interventions that are gender specific and that focus on increasing intention to exercise regularly.