Angular momentum in skilled kicking pullover performed by elementary school children

その他

This study aimed to clarify the differences in body positions and the role of the swing leg, support leg, and head-arm-trunk segment in generating and maintaining angular momentum of the whole body about a horizontal bar as well as how to improve the skill level of successful kicking pullover attempts. Two-dimensional kinematic parameters of successful kicking pullover attempts and body composition indices of 26 fifth-grade elementary school children were collected. Their techniques were classified into excellent and good groups based on the subjective evaluation of three evaluators. Although there were no significant differences in body composition indices between the two groups, the motion phase time during the 4th phase and the total time of the excellent group were significantly shorter compared with the good group. Also, the counterclockwise rotation of the angular momentum of the head-arm-trunk segment and the whole body during the 4th phase was significantly larger in the excellent group than in the good group. These results suggest that maintaining the angular momentum of the head-arm-trunk segment during the 4th phase leads to attempts with shorter time and improves skill levels from the good group to the excellent group. The good group was not able to maintain angular momentum of the whole body during the 4th phase because the peak of the angular momentum of the head-arm-trunk segment and support leg tended to appear earlier than in the excellent group. we newly clarified that teachers need to focus on the body position of the trunk and head during the 4th phase in order for elementary school children to succeed in kicking pullovers more beautifully at a higher level.