2015 年 64 巻 4 号 p. 443-451
This study aimed to examine the relationship between daily outdoor playing time assessed using questionnaires for parents and daily moderate-to-vigorous physical activity (MVPA) using triaxial accelerometers for young children (213 boys: 5.8±0.6years and 193 girls: 5.9±0.6years). The study also examined the potential relationships between daily MVPA and exercise habits or familial and preschool factors which were assessed using questionnaires for parents. Daily MVPA was assessed using a triaxial accelerometer (ActivTracer, GMS) for 6 consecutive days, including weekdays and weekends. Outdoor playing time and percentage of outdoor playing time more than 60 min/day were 81±62 min/day and 64% for boys and 78±61 min/day and 62% for girls, respectively. Outdoor playing time was not significantly correlated with MVPA. The study found that no factors for MVPA, including exercise habits, were correlated with MVPA when adjusted for age, body height and log-body weight, except that MVPA for girls in kindergartens was higher than that in nursery schools. These findings suggest that the percentage of outdoor playing time more than 60 min/day was about 2/3 in young children. The questionnaire didn't reflect their MVPA. The factors used in the present study except for the preschool type for girls may not contribute to the time spent in MVPA in preschool children.