[Objective]The objective of this research was to clarify the relationship between variable factors(exercise habits and lifestyle)and non-variable factor(seasonal factors)with the number of walking steps count and physical fitness of young children. [Methods]Subjects were 667 children(third grade or higher)attending elementary schools in the city of N. We conducted a survey on the number of walking steps taken by the subjectsʼ and their lifestyles for 5-days in June 2009 and January 2010, and the relationship with physical fitness test scores was investigated. Children were grouped based on exercise habits, time spent viewing television and physical fitness test scores. [Results]The number of walking steps taken within the whole day and steps taken- after school were both lower in January than in June. However, there was no decrease in steps taken at school. Analysis of variance demonstrated a significant effect on the daily number of walking steps for the regular exercise factors and seasonal factors. Multiple comparison revealed that the number of walking steps was highest in the regular exercise group followed by the irregular exercise group then the non-exercise group. The number of walking steps was higher in June than in January for boys in the regular exercise group and girls in all groups. Furthermore it was higher in children who watched TV for a short time than in those who watched longer, but the proportion of children in the short TV time group tended to decrease in January. The number of walking steps was also higher in the group with high scores on physical fitness test than in the group with low scores. These findings demonstrate that seasonal factors 〈non-variable factor〉lead to a decrease in the number of walking steps and exercise participation rate and an increase in the length of television viewing time. The results also suggest that regular exercise〈variable factor〉(target step count of 16,000 steps/day for boys, 14,000 steps/day for girls)and restricting television viewing hours〈variable factor〉(1h/day or less)may lead to increase the number of walking steps and help children to promote their long-term physical fitness.
Objective:The present study examined physical activity(PA)levels and differences in PA by gender and grades during school recess periods. Method:PA levels of two hundred and thirty children(55% boys, 42%younger)from two elementary schools in Japan were measured with accelerometry for seven consecutive days. Time spent in sedentary, light PA, moderate PA, vigorous PA during break(25 minutes)and lunch recess(15 minutes), and total recess(40 minutes)was determined. Two-way analysis of variance was used to examine differences in PA variables by gender and grades. Results:Data of one hundred and eighty four children(52% boys, 56% younger)was available. Time spent in sedentary, light PA, moderate PA, and vigorous PA was 8.5±4.9, 12.9±3.8, 1.6±1.2, and 2.9±2.8 minutes during break, and 3.5±2.5, 9.5±2.2, 1.4±0.9, and 1.6±1.4 minutes during lunch recess, respectively. There were no significant interactions between gender and grades. Significant main effects of PA variables were found for gender and grades. Boys had fewer sedentary time(p=0.017)and higher vigorous PA time(p<0.001)than girls during total recess. Younger engaged in more sedentary(p=0.045)and less light(p=0.023)and moderate PA(p=0.006)than older at break. On the other hand, at lunch recess, younger had significantly longer light(p=0.015)and vigorous PA(p<0.001)and shorter sedentary time(p<0.001)than older. Conclusion:Overall, boys were less sedentary and engaged in PA at higher intensity levels than girls during school recess. Different pattern in PA was shown between break and lunch recess by grades.