Impact of implementing and lifting COVID-19 lockdown on study and physical activity patterns among youths in China.

The youths' PA level have generally decreased and study patterns significantly changed during and after lockdown in China. Our results would inform policy-makers and education administrators of the declined PA levels and changed study patterns among youths during COVID-19 lockdown for better policy making. In-class and/or extracurricular PA programs could be designed to counteract those effects under cooperation of youths' parents.