Screen time and seasonal variation in physical activity among preschool children in Edmonton
The prevalence of childhood overweight and obesity is increasing worldwide. One main determinant of overweight and obesity is inactivity. Little is known about the factors that influence physical activity and sedentary behaviour among young children. Seasonal variation was examined as a correlate of physical activity in both a literature review and in a sample of pre-school children in Edmonton, Alberta. Neighbourhood socioeconomic status (SES) was examined as a correlate of screen time use in
... screen time use in the same sample of children. Methods: For study 1, databases were searched for studies on seasonal variation in physical activity levels. Studies 2 and 3 involved a sample of 4-and 5-year-old children, who were attending a health center in and around Edmonton, Alberta for preschool immunization between November, 2005 and August, 2007. Parents provided proxy reports of their children's screen time viewing and physical activity. Height and weight were measured by a trained health assistant and body mass index (BMI) was calculated. Children's postal codes were retrieved from health records to calculate neighbourhood SES through census data. The month the proxy report was completed was used to determine seasonality. Several regression models were constructed to examine relationships between variables in studies 2 and 3. Results: The review of literature revealed that 83% (29/35) of the studies found seasonal variation in physical activity among children and/or adolescents. For study 2, total physical activity as well as active play, weekday and weekend minutes were highest in the summer and lowest in the winter. Finally, neighbourhood SES was a predictor of screen time and TV/video use for girls but not for boys in study 3.