标题：Learning Outcomes for Physical Education in Long Jump: Is it Possible for 5th Graders to Learn Take-off Techniques that Enable Greater Vertical Velocity?*
期刊名称：International Journal of Sport and Health Science
印刷版ISSN：1348-1509
电子版ISSN：1880-4012
出版年度：2019
卷号：17
页码：A37-A53
DOI：10.5432/ijshs.17016
语种：English
出版社：日本体育学会
摘要：The purpose of this study was to determine whether physical education lessons focusing on the long jump for elementary school fifth graders would be able to improve their vertical jump velocity. Twenty-eight elementary school fifth graders were instructed in the long jump over 5 lessons. To gain a higher vertical velocity, participants were instructed to pull their swing legs forward at the instant of touchdown for take-off and to lean their trunks backward during take-off. Measurements were taken during the first and fifth lessons. To evaluate the jumping motion, the body's center of gravity and segment angles were obtained using a high-speed video camera from a side angle.The main results were as follows:1) Since vertical velocity at toe-off and jumping distance were both significantly increased, elementary school fifth graders were able to learn take-off motion to gain a higher vertical velocity. However, the increase in jumping distance was not due to the increase in vertical velocity but rather a decrease in the distance lost during landing.2) Although post-measurement showed that the swing legs at touchdown for take-off were pulled more forward than in pre-measurement, the change in that motion did not contribute to the increased vertical velocity.3) In post-measurement, the trunk was inclined smaller during take-off than in pre-measurement. Therefore, forward rotation of the body during take-off was suppressed, which increased the vertical velocity. In addition, suppressing the forward rotation of the body strongly contributed to the decrease in distance lost during landing.
关键词：motion analysis;jumping motion;behavior of center of gravity
