title: Daily physical activity in japanese preschool children evaluated by triaxial accelerometry: the relationship between period of engagement in moderate-to-vigorous physical activity and daily step counts.
abstract: The purpose of the present study was to evaluate moderate-to-vigorous physical activity using triaxial accelerometry in Japanese preschool children. The relationship between daily step counts as a convenient measure of physical activity and minutes of engagement in moderate-to-vigorous physical activity was also examined. Physical activity was assessed using a triaxial accelerometer (ActivTracer, GMS) and daily steps using a uniaxial accelerometer for 6 consecutive days, including weekdays and weekend days, in 157 four- to six-year-old Japanese children attending kindergarten or nursery school. Using triaxial and uniaxial accelerometers, nonlocomotive activities and step counts for young children can be evaluated, respectively. Average daily moderate-to-vigorous physical activity (physical activity ratio >or=3) and step counts were 102 (+/-32) min/day and 13,037 (+/-2,846) steps/day, respectively. A strong and significant correlation was observed between minutes of moderate-to-vigorous physical activity and step counts (r=0.832, p<0.001). The daily step counts corresponding to 60 min, 100 min, and 120 min of moderate-to-vigorous physical activity were 9,934, 12,893, and 14,373 steps/day, respectively. The correlation coefficient between minutes of higher intensity activities (physical activity ratio >or=4) and step counts was slightly lower (r=0.604, p<0.001). The daily step count corresponding to 30 min of the higher intensity activities was 14,768 steps/day. These results suggest that approximately 13,000 steps/day are required for preschool children to engage in more than 100 min of moderate-to-vigorous physical activity.
authors.affiliation: Division of Integrated Sciences, J. F. Oberlin University, Machida, Tokyo 194-0294, Japan. c-tanaka@obirin.ac.jp
authors.forename: Chiaki
authors.initials: C
authors.lastname: Tanaka
authors.forename: Shigeho
authors.initials: S
authors.lastname: Tanaka
mesh_terms: D000054:Acceleration; D001481:Basal Metabolism / Q000502:physiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007564:Japan; D016014:Linear Models; D008297:Male; D018670:Monitoring, Ambulatory / Q000379:methods; D009043:Motor Activity / Q000502:physiology*