Bélair, Marc-André2015-10-092015-10-0920152015http://hdl.handle.net/10393/33022http://dx.doi.org/10.20381/ruor-4099Introduction: Mood disorders are a serious burden on Canadians. Physical and sedentary activity are easily modifiable risk factors for many diseases. An association with depression could have important implications Objective: To investigate any cross-sectional or longitudinal association between physical activity, sedentary activity, and depression in the National Longitudinal Survey of Children and Youth (NLSCY). Methods: These studies used both a stacked cross-sectional and a trajectory/latent class analysis design Univariate and multivariate multinomial logistic regressions were used to assess the relationship between physical and sedentary activity and depression using the emotional disorder-anxiety scale for children and youth available in the NLSCY. Results: When accounting for covariates, physically inactive respondents had increased odds of higher depressive symptom scores. Sedentary activity was only statistically significantly associated with depressive symptoms in the cross-sectional design. Conclusions: Physical inactivity is significantly associated to depressive symptomatology. The relationship between sedentary activity and depression is inconclusive.enEpidemiologyMental HealthPhysical ActivitySedentary ActivityDepressionSuicideSuicidal IdeationLongitudinalCross-SectionalTrajectory AnalysisLatent Class AnalysisChildrenYouthAdolescentsYoung AdultsSurveyThesis