Prospective associations between early childhood screen time trajectories during the Covid-19 pandemic and accelerometer-measured physical activity by age 5

Design : A longitudinal cohort study of Canadian parents with preschoolers.

Setting : Data were collected in Nova Scotia, Canada, during the COVID-19 pandemic in Spring/Summer 2020 and 2021, and Summer/Fall 2022.

Sample : A community-based convenience sample of 315 parents of preschool-aged children (54% boys) was followed longitudinally when children were 3.5 (2020), 4.5 (2021), and 5.5 years old (2022).

Methods : Parent-reported screen time at 3.5, 4.5, and 5.5 years was used to estimate preschooler screen time trajectories. Using growth mixture modeling (GMM), three groups were identified: low (mean = 0.89 h/day, 23%), average (mean = 2.96 h/day, 56%), and high (mean = 6.42 h/day, 21%) screen time trajectory groups. At age 5.5, physical activity was directly assessed using accelerometers to capture light, moderate, and vigorous-intensity physical activity. Parents also reported child sex, family configuration, and educational attainment.

Results : Children in the high screen time trajectory group engaged in significantly less light-intensity physical activity (b = −29.98, P < .05) compared to children in the average screen time trajectory. No significant differences were observed between the low and average screen time trajectory groups for light-intensity physical activity. Additionally, no significant differences in moderate or vigorous-intensity physical activity were observed between the screen time trajectory groups.

Conclusions : Higher screen time in preschoolers is associated with reduced engagement in light-intensity physical activity. These findings highlight the importance of monitoring screen time to ensure that children have opportunities to engage in light-intensity physical activities such as active and outdoor play. Limiting early childhood screen time may support healthier physical activity patterns and promote early childhood development.