Brief report: Longitudinal associations between sedentary behaviours and depressive symptoms in adolescent girls

• Bidirectional associations between youths’ sedentary behaviours and depression were examined
• Depressive symptoms and sedentary behaviours increased over time.
• Baseline levels of depressive symptoms were predictive of change in sedentary behaviours.

The purpose of this study was to examine longitudinal associations between sedentary behaviours (SB) and depressive symptoms in adolescent girls. Participants (n = 341) completed the self-report ecological momentary assessments diary for the measurement of sedentary behaviours and completed the Center for Epidemiological Studies Depression scale (CES-D) at three time points during a 4-year period. The association between SB and depressive symptoms over time was examined with latent growth models. Both depressive symptoms and SB increased over time. Baseline levels of depressive symptoms were predictive of change in SB, but initial levels of SB did not predict changes in depressive symptoms. These prospective associations remained controlling for age, home electronic equipment and socioeconomic status.