Are overweight students in Grades 3, 7, and 11 less physically active than their healthy weight counterparts?

Objective. This study compared the accumulated minutes of objectively measured physical activity in 1 790 boys and girls in Grades 3, 7, and 11 classified as healthy weight, at risk of overweight, and overweight. Methods. Height and weight were measured and body mass index calculated. Minutes of sedentary, light, moderate, hard, and very hard physical activity were obtained from a seven-day measurement of physical activity using an accelerometer (Actigraph, mode 7164; MTI). Results. In Grade 3, boys (p=0.000) and girls (p=0.012) classified as overweight obtained significantly fewer minutes of very hard physical activity compared with their healthy weight counterparts. Boys in Grade 7 considered overweight obtained significantly fewer minutes of hard (p=0.002) and very hard physical activity (p=0.006) compared with boys who were a healthy weight. There were no significant differences in minutes of sedentary, light, moderate, hard, or very hard intensity physical activity in the boys and girls in Grade 11, who were considered a healthy weight, at risk of overweight, or overweight. Conclusions. Weak and inconsistent support was provided for the notion that boys and girls classified overweight are less physically active than their healthy weight counterparts.