Outdoor play in children: associations with objectively-measured physical activity, sedentary behavior and weight...

To determine the amount of time children play outdoors and examine associations with weekday, weekend and after-school physical activity (PA), sedentary behavior (SB), and weight-status (normal-weight, overweight/obese).

Data were extracted from Project BEAT (Toronto, 2010-2011; www.beat.utoronto.ca). Children's (n=856; mean age=11±0.6years) PA and SB were measured using accelerometry. Outdoor play (OP) was assessed via parental report and collapsed into three categories (<1h/day, 1-2h/day, >2h/day) and differences in anthropometric and PA characteristics were assessed.

55.1%, 37.2%, and 7.7% of children played outdoors for <1h/day, 1-2h/day and >2h/day, respectively, on weekdays. OP was higher on weekends and in boys. OP was associated with SB, light PA and MVPA at all time-points, whereby children attaining <1h/day had lower activity profiles. Boys playing outdoors for <1h/day were more likely to be overweight/obese and had lower PA levels than normal weight boys. However, overweight/obese boys who spent >2h/day playing outdoors had PA profiles similar to normal weight counterparts.

Encouraging children to spend more time outdoors may be an effective strategy for increasing PA, reducing SB, and preventing excess weight gain (particularly boys' play).