The present study was designed to investigate the development and the sex difference of a rapidly repeating movement of the whole body observed from ground reaction forces exerted during the side jump. Subjects were 246 healthy females aged 5-17 years, and their physique (body height, body mass, skinfold thickness: upper arm back + scapula lower) and side jump were measured. The procedure of the side jump was hopping between two parallel lines on the force plate from right to left alternately as quickly as possible. The distance between the lines was fixed at one third of the mean body height at each age. Ground reaction force curve deduced from force plate was measured on the jumping frequency per second, the times on the ground and in the air, the maximum values of vertical and horizontal force, the vertical and horizontal components of impulses and the kicking angle calculated from vertical and horizontal impulses. These ground reaction forces and impulses (half value of the impulse was used for the repeating movement) were calculated the value per body mass, and these values were converted into the unit of acceleration and velocity, respectively. The frequency of the side jump per second for females similarly increased by around 11 years with males, and it significantly decreased in comparison with males afterwards. Both times on the ground and in the air for females were similarly shortened by around 11 years with males, and these times were significantly extended in comparison with males afterwards. The maximum vertical acceleration for males and females was no the remarkable change, but the value of females was the value which was smaller than males a little. The maximum horizontal acceleration for females similarly increased by around 13 years with males, and it significantly decreased in comparison with males afterwards. The vertical velocity for females similarly decreased by around 9 years with males, and it significantly increased in comparison with males afterwards. The horizontal velocity for males and females was no the remarkable change. The kicking angle of females similarly decreased by around 13 years with males, and it significantly increased in comparison with males afterwards. These results suggest that the rapid repeating frequency for females decreases by the cause such as 1) the horizontal component remarkably low in comparison with vertical component of force, 2) the time on the ground is extended in order to obtain both vertical and horizontal velocities, 3) the time in the air is extended by the increase in the kicking angle. The increase of the body fat volume of females seems to be concerned in the background of this sex difference.
内容記述
論文
雑誌名
三重大学教育学部研究紀要. 自然科学
巻
54
ページ
47 - 54
発行年
2003-03-01
ISSN
0389-9225
書誌レコードID
AN00234199
フォーマット
application/pdf
著者版フラグ
publisher
その他のタイトル
ユカ ハンリョク カラ ミタ ゼンシン キュウソク ハンプク ドウサ ノ ハッタツ ト セイサ
Development and Sex Difference of a Rapidly Repeating Movement of the Whole Body Observed from the Ground Reaction Force