Finding the balance: The influence of movement behaviours on childhood behaviour problems

Background and aims The Canadian 24-h movement guidelines have led to an increased focus on movement behaviours (sleep, screen, sedentary, and physical activity) throughout the day. Methods We examined the cross-sectional and longitudinal associations between 24-h movement behaviours and parent-reported levels of internalizing, externalizing, and total behaviour problems in a subset of the [Study Name] birth cohort study at ages 3 (N Age 3 = 541, 48.1% girls) through 5 (N Age 5 = 575, 49.6% girls). Physical activity, sedentary time, and sleep were measured using an accelerometer worn on the non-dominant wrist for seven days following a 24-h protocol. Screen time was measured via parent-report and date-matched to daily accelerometer recordings. Compositional isotemporal substitution models predicted change in behaviour problems with reallocating time between movement behaviours. Results Cross-sectional analysis indicated that screen time relative to other movement behaviours was associated with greater externalizing behaviours at age 3 and greater internalizing and total problem behaviours at ages 3 and 5. This was supported in the longitudinal analysis, where increased screen time at 3 was associated with increased internalizing, externalizing, and total problem behaviours at 5. Cross-sectional reallocation from screen to non-screen sedentary time was associated with reductions in internalizing and total behaviour problems at 3 and 5 years and reductions in externalizing at 3. Contrary to previous findings, cross-sectional proportional increases in moderate-to-vigorous-intensity physical activity were associated with increased externalizing and total problem behaviours at 5. Conclusions Clinicians should prioritize supporting families to find a balanced approach rather than promoting specific movement behaviours.