Impact of COVID-19 pandemic lockdown on movement behaviours of children and adolescents: a systematic review.

Introduction: Several studies have examined how the lockdown restrictions enforced to halt the spread of COVID-19 have affected children and adolescents' movement behaviours, but there is a need to synthesise these findings. Therefore, we conducted this systematic review to examine the impact of COVID-19 lockdown on children and adolescents' movement behaviours.

Methods: We searched eight databases and grey literature for relevant studies of all study designs; and conducted a narrative analysis of the results following synthesis without meta-analysis guidelines. We used appropriate tools to assess the risk of bias in quantitative and qualitative studies. We compared changes in physical activity, screen time and sleep duration and quality from before to during the COVID-19 lockdown.

Results: This review included 71 studies reporting data from 35 countries and territories, mostly from high-income economies. A majority of the studies used a cross-sectional design and had fair to poor-quality ratings. Most studies reported reduced physical activity, increased screen time and longer sleep hours among children and adolescents. Children and adolescents facing strict lockdowns saw a larger decline in physical activity and a sharper increase in screen time than those under mild restrictions.

Conclusion: COVID-19-related lockdowns were detrimental to children and adolescents' movement behaviours, with stricter lockdowns tending to have a bigger impact. Children and adolescents under COVID-19 restrictions are likely to be less active, spend more time on screen, and sleep longer hours than before the lockdown. More studies from low-income and middle-income countries could provide a clearer picture of the impact.

Prospero Registration Number: CRD42021245924.