It is recommended that preschool children perform at least 60 minutes of physical activity per day. However, preschool children in nursery schools have a lot of sedentary action time even during the an exercise program. This study aimed to clarify physical activity intensity and activity time during the exercise program in the room, and the 2nd aim of this study is to indicate the reference value of moderate intensity and vigorous intensity of physical activity using running. The target group was selected as the 5 year-old class attending a nursery school (8 boys and 8 girls). The targeted exercise program is to imitate an animal movement and skip in sync with music. Physical activity intensity, activity time and the number of steps during the exercise program were measured using Lifecorder. Physical activity intensity by the Lifecorder was evaluated as 0–3 as low intensity, 4–6 as moderate intensity, 7–9 as vigorous intensity. Low intensity %time in the exercise program was 87.1±1.8% for boys, and 87.4±1.0% girls, respectively. Moderate intensity %time in the exercise program was 3.0±0.8% for boys, and 2.3±0.7% girls, respectively. And, vigorous intensity % time in the exercise program was 9.9±1.1% for boys, and 10.3±0.6% girls, respectively. From the above, it was suggested that moderate and vigorous intensity physical activity by the targeted exercise program implementation is less than 15% of exercise program time. Furthermore, the running speed evaluated as moderate intensity in preschool children was estimated to be 1.83 m/sec (50% of maximum speed). In addition, the running speed evaluated as high intensity was estimated to be 3.25 m/sec (70–80% of maximum speed). These results suggested that the reference value of the physical activity intensity is considered to be effective for the evaluation of the physical activity intensity of preschool children within daily activities.
