Submitted to: Journal of Sports Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/18/2005
Publication Date: 3/1/2006
Citation: Jago, R., Watson, K., Baranowski, T., Zakeri, I., Yoo, S., Baranowski, J., Conry, K. 2006. Pedometer reliability, validity and daily activity targets among 10- to 15-year-old boys. Journal of Sports Sciences. 24(3):241-251. Interpretive Summary: Little has appeared in the literature on the reliability and validity of pedometers (a relatively low cost instrument) as indicators of physical activity among children. This study demonstrated that pedometers were reliable and valid against concurrent measurement by accelerometers. A pedometer count of 8000 steps in 60 min or less would be an indicator of 60 min of moderate to vigorous physical activity.
Technical Abstract: The aims of this study were to: (1) determine whether the number of pedometer counts recorded by adolescents differs according to the adiposity of the participant or location on the body; (2) assess the accuracy and reliability of pedometers during field activity; and (3) set adolescent pedometer-based physical activity targets. Seventy-eight 11- to 15-year-old Boy Scouts completed three types of activity: walking, fast walking, and running. Each type was performed twice. Participants wore three pedometers and one activity monitor during all activities. Participants were divided into groups of normal weight (BMI < 85th percentile) and at risk of being overweight (BMI > 85th percentile). Intra-class correlations across the three activities indicated reliability (r = 0.51 – 0.92, P < 0.001). This conclusion was supported by narrow limits of agreement that were within a pre-set range that was practically meaningful. Multivariate analysis of covariance indicated adiposity group differences, but this difference was a function of the increased stature among the larger participants (P < 0.001). Ordinary least-squares regression models and multi-level regression models showed positive associations between the number of pedometer and activity monitor counts recorded by the three groups of participants during all activities (all P < 0.001). The mean number of counts recorded for all participants during the fast walk was 127 counts per minute. In conclusion, the pedometers provided an accurate assessment of adolescent physical activity, and a conservative estimate of 8000 pedometer counts in 60 min is equivalent to 60 min of moderate to vigorous physical activity.