Do movement behaviours influence the association between early menarche and depression symptoms among Brazilian adolescents?

Early menarche has been associated with adverse health outcomes, such as depressive symptoms. Discovering effect modifiers across these conditions in the pediatric population is a constant challenge. We tested whether movement behaviours modified the effect of the association between early menarche and depression symptoms among adolescents.

Associations between anxiety disorders and depression symptoms are related to 24-hour movement behaviors among Brazilian adolescents.

Background: We tested whether 24-hour movement behaviors modified the effect of the association between anxiety and depression symptoms among adolescents.

Methods: This cross-sectional study included 4141 adolescents aged 15 to 19 years (50.0 % females) across all Brazilian geographic regions.

The association of physical activity, sleep, and screen time with mental health in Canadian adolescents during the COVID-19 pandemic: A longitudinal isotemporal substitution analysis.

Background: The impact of COVID-19 on adolescent mental health is a global concern. Increased screen time and reduced physical activity due to the lockdown measures have been linked to detrimental mental health outcomes; however, the literature remains limited by cross-sectional and retrospective designs, and consideration of behaviours in isolation. Prospective evidence is necessary to examine whether moderate-to-vigorous physical activity (MVPA), sleep and screen time influenced changes in mental health.

Changes in Canadian Adolescent Time Use and Movement Guidelines During the Early COVID-19 Outbreak: A Longitudinal Prospective Natural Experiment Design.

Background: Comprehensive, prospective, longitudinal data are lacking on the effects of the COVID-19 outbreak on adolescents' movement behaviors (moderate to vigorous physical activity [MVPA], sleep, recreational screen use, and strengthening exercises). The purpose was to compare movement behavior changes among adolescents affected by the pandemic with controls.

Methods: Survey data from 10,659 students at 82 Canadian secondary schools (aged 12-19 y) during the 2018-2019 and 2019-2020 school years were analyzed.