The purpose of this study is to clarify the relationships between anthropometric measures, percent body fat, life history (exercising habits, fracture history, menarche etc.), and calcaneal bone stiffness. Five hundred and seventy-six elementary school students of both sexes participated in this study as the subjects.
In the 6th grade, the height, weight, and percent body fat of the female students became higher than those of the male students. In response to these variations, the calcaneal bone stiffness of the female students became higher, which was caused by the earlier incidence of secondary sex character in the female students than in the male students. There was significant positive correlation between the anthropometric measures and the calcaneal bone stiffness in the 5th and 6th grade students of both sexes. Moreover, there was significant positive correlation between the percent body fat and the calcaneal bone stiffness in 3rd and higher grade female students. The calcaneal bone stiffness of the 4th to 6th grade female students who had long playing time after school was significantly higher than that of those who had short playing time. Furthermore, the calcaneal bone stiffness of 4th to 6th grade male students and 1st to 3rd grade female students who participated in the activities of the juvenile sports association or a sports club was significantly higher than that of counterpart students who did not participate in such activities. The calcaneal bone stiffness of the 5th and 6th grade female students with menarche was significantly higher than those without menarche.
From these results, the character of calcaneal bone stiffness in the elementary school students is elucidated and it is revealed that the height, weight, percent body fat, and exercising habits have influence on the calcaneal bone stiffness to some degree even in elementary school students while the beginning of menarche has huge influence on it.

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Body image in children was considered from the relationship between body parts and basic motor skills, and the relation between human figure drawing and body image was revealed with the developmental perspective taken into consideration. Through four developmental periods, the results of considering the relationship between body parts and basic motor skills revealed the following. For standing broad jump and balance endurance times, results indicating the same tendency were obtained in a comparison of four-year olds and five-year olds in which four-year olds through five-year olds were divided into four groups. Also, for four-year olds, a positive correlation was found between body parts related to the four extremities and basic motor skills such as running, jumping and throwing. From these results, together with four-year olds and five-year olds, for basic motor skills, it was possible to surmise that the children have an awareness of body image of which body parts are involved in which basic motor skills, thus supporting the introspective reporting results gathered through interview surveys. Especially for softball throwing, we can surmise that four-year olds are aware of their four extremities, contributing to body image. Meanwhile, the experience of five-year olds knowing that to be able to run fast requires a stable running form suggested that they are able to clearly visualize the upper body and related parts. It was revealed that for awareness of the body parts, improvement of basic motor skills such as running, jumping and throwing is closely related to an individual's body image.

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