Prospective Associations Between Early Childhood Screen Time Trajectories During the COVID-19 Pandemic and Accelerometer-Measured Physical Activity by Age 5.

PurposeTo examine associations between preschooler screen time trajectories and physical activity outcomes at age 5.5.DesignA longitudinal cohort study of Canadian parents with preschoolers.SettingData were collected in Nova Scotia, Canada, during the COVID-19 pandemic in Spring/Summer 2020 and 2021, and Summer/Fall 2022.SampleA 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).MethodsParent-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.ResultsChildren 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.ConclusionsHigher 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.