Abstract
This study was undertaken to determine the motor ability, daily physical activity, and bone density in 3- to 6-year-old Japanese preschool children (n = 1159, boys = 606, and girls = 553), and also to study the relationship among motor ability, daily physical activity, and bone density in this population. We measured the subjects’ motor ability while they performed 6 events, studied their daily physical activity using Lifecorder throughout the day for 7 consecutive days, and measured bone speed of sound (SOS) using quantitative ultrasound. We found that in both sexes, the step counts and the amount of exercise in the groups with high motor ability were the highest, and in boys, the values for the group with high motor ability were significantly higher than those for the groups with intermediate and low motor ability (p < 0.05–0.01). Similarly, the bone SOS of the group with high motor ability was the highest in both sexes, and in boys, value for the group with high motor ability was significantly higher than that for the group with low motor ability (p < 0.05). It was suggested that increased daily physical activity may improve the motor ability and bone SOS in preschool children boys. Furthermore, preschoolers who perform vigorous physical activity may get accustomed to this level of activity, which may afford health benefits throughout their life.
