Abstract
[Purpose] In this study, we investigated the gender differences in physique and motor fitness of preschool children, and the relationship between physique and motor fitness, and the muscle thickness measured by an ultrasound. [Subjects and methods] The subjects were 44 healthy preschool children (26 boys, 18 girls). We evaluated their body height, body weight, quadriceps femoris muscle thickness (measured by the ultrasound imaging system), muscle stiffness, foot grasp strength, grip strength, and standing long jump distance. All these measures were compared between two groups of boys and girls,and the relationship between each item was examined. We also conducted a multiple regression analysis using muscle thickness as the dependent variable, and all other variables as the independent variable. [Results] None of the items exhibited a significant difference between the boys and girls. Further, we found a significant relationship between muscle thickness and body height and weight. Body weight was found to independently influence muscle thickness. [Conclusion] Our findings suggested gender differences in preschool childrenʼs physique and motor fitness. We also found a significant relationship between muscle thickness and body height and weight. These findings indicated that body weight independently influenced muscle thickness.
