Abstract:
Objective Based on the objectively-measured levels of physical activity, the bout patterns of physical activity in preschool children were examined using high-frequency epoch.
Methods Based on informed and voluntary principles, 306 pre-school children were recruited in Shanghai's Yangpu District and Baoshan District. Participants'physical activity were assessed using ActiGraph GT3X accelerometers, which were worn for seven consecutive days. Each physical activity is classified by intensity and duration, and then the average daily frequency of activities with different durations and the ratio of the total cumulative activity time were counted.
Results A total of 146 participants(boys, 85;girls, 61;mean age=57.7±5.0 months)had all 7 days of valid measurement data, which were included in the final statistical analysis. Findings of this study indicate that the average duration of each physical activity lasted less than 4 seconds, while more than 70% of the MPA and VPA duration were from 2 to 3 seconds.
Conclusions Preschool children's physical activity is dominated by sporadic activities with short duration. In order to accurately measure the total amount of physical activity in preschool children, especially the moderate to vigorous physical activity, a shorter epoch, such as 3 seconds or even shorter, should be used.