Measuring Children's Activity Levels: The Association Between Step-Counts and Activity Time

Abstract

Background: The primary purpose of this study was to describe the association between activity time and step counts in children.

Methods: Subjects were 590 students (334 girls, 256 boys) with each gender having a mean age of 9.2 ± 1.8 y. All subjects wore the Walk4Life 2505 pedometer for four consecutive weekdays. This pedometer simultaneously measures both step counts and activity time.

Results: Boys accumulated significantly more minutes of activity time/day (140.9 ± 39.6 vs. 126.3 ± 38.1), steps/day (13,348 ± 4131 vs. 11,702 ± 3923), and steps per min (93.99 ± 5.8 vs. 91.85 ± 5.8) than girls (P < 0.001) Steps/day was a significant predictor of activity time/day (P < 0.0001).

Conclusions: Boys accumulate more steps per day and more activity time per day than girls. There is a strong association between steps per day and activity time in children. Daily steps per minute as a measure of free living physical activity in children is explored.

Keywords: children; physical activity measurement.