Comparison Of Physical Activity And Sedentary Behavior In Obese And Non-obese Children

Abstract

It is widely believed that lack of physical activity is important in the development and maintenance of childhood obesity. However, studies comparing physical activity in obese and non-obese children have reported inconsistent results and sedentary behavior has not been measured objectively. Purpose To test the hypothesis that obese children are less physically active and more sedentary than non-obese children. Methods Physical activity and sedentary behavior was measured objectively over a 7-day period using CSA accelerometers in 57 obese children (BMI >98th centile) and 57 non-obese children pair-matched for age and gender (mean age 8 years SD 2; 29 males/28 females). Total physical activity [accelerometry count per minute (cpm) averaged over the monitoring period], percentage of monitored time spent in sedentary behavior, light intensity activity and moderate to vigorous physical activity (MVPA) were determined. Results There was a trend for total physical activity (mean cpm) to be higher in the non-obese group compared to the obese group (717 vs 681; 95%CI −3 to 152). The percentage of monitored time spent in sedentary behavior was 80.3% in the obese group and 80.0% in the non-obese group respectively, with no significant difference between the groups (95%CI −4.0 to 0.5). Light intensity activity was similar in the obese and non-obese groups (16.1% vs 16.9%; 95%CI −0.3 to 3.0). Participation in MVPA was significantly higher in the non-obese group compared to the obese group (4.0% vs 2.5%; 95%CI 0.7 to 2.1). CONCLUSIONS Results from this study support the hypothesis that obese children are less active than non-obese children. Although, the difference in MVPA between the groups was small (1.5%). In contrast, sedentary behavior was similar in both groups. In both groups, engagement in sedentary behavior was high (80%) and participation in moderate to vigorous activity was low (<5%), which equates to less than 30 minutes of MVPA per day.