This study examined whether there was a significant seasonal variation in objectively measured habitual physical activity and sedentary behavior in young children. Participants were children who attend nursery in Glasgow, Scotland, and measurements were taken using uniaxial accelerometry over 3 to 6 days. There were small but significant seasonal associations with physical activity and sedentary behavior (ANOVA: p < .001 in both cases). Total physical activity (accelerometry cpm) was significantly lower in spring than in summer, fall, and winter. We also found slight but significant seasonal variations in time spent in low-intensity activity and in moderate-to-vigorous-intensity activity. Sedentary time was significantly lower in summer vs. spring and in fall vs. spring. The present study suggests that seasonality plays only a limited role in physical activity and sedentary behavior in young children in our setting. Single measures of these variables should be adequate for research purposes in the absence of marked seasonal variability. In our sample and setting, the limited degree of seasonality precluded identification of major seasonal barriers to and opportunities for physical activity.
Fisher, Reilly, Montgomery, Kelly, Williamson, and Paton are with the University of Glasgow, Division of Developmental Medicine, Yorkhill Hospitals, Glasgow, Scotland; Williamson is also with the Glasgow City Council Education Department, Glasgow, Scotland. Jackson is with the Division of Energy Balance and Obesity, Rowett Research Institute, Bucksburn, Aberdeen, Scotland. Grant is with University of Glasgow, Faculty of Biological and Life Sciences, West Medical Building, Glasgow, Scotland.