Background: Movement improves remarkably during childhood, but it depends heavily on the development of toe muscle strength and the growth of the sole form.
Objective: This study examined differences in the left and right feet, sex differences, and changes based on age in the toe muscle strength and foot form; it also studied inter-relations between them in children aged 5–10.
Methods: Subjects were 287 boys and girls enrolled in a kindergarten and an elementary school in 2016 and 2017.
Measurement items: Height, weight, toe muscle strength, and foot length, foot width, heel width, center of gravity position, and internal and external arches in the left and right feet were measured.
Results and Conclusion: Toe muscle strength, foot length, foot width, heel width, center of gravity position, and internal and external arches increased with age. However, there were no or negligible differences in the left and right feet and as per sex.
Toe muscle strength had low relations to height, body weight, foot length, foot width, heel width, and center of gravity position. There was no relation between toe muscle strength and arches.
Foot length, foot width, heel width, and center of gravity position were all related to height and weight.
In particular, foot length had a close relation to height.
Although the foot length, foot width, and heel width were related to each other, the relation between the internal and the external arches was low. The arches also had low relationships to the other sole variables.
