著者

藤井 宏明 藤井 範久

出版者

日本バイオメカニクス学会

雑誌

バイオメカニクス研究 (ISSN:13431706)

巻号頁・発行日

vol.25, pp.14-27, 2021 (Released:2021-10-09)

参考文献数

19

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The purpose of this study was to investigate the body movements to generate handle velocity in the tangential and the radial direction of hammer head during the hammer throw turn. The positive leading distance of handle has the effect of accelerating the hammer head in hammer throw. In addition, the increase and decrease of the leading distance of handle are consistent with the increase and decrease of handle velocity in the radial direction of hammer head. It will be important to clarify the movement of the body for the acquisition of the leading distance of handle by examining the acquisition of the handle velocity in the radial direction by the body movement. Throwing motions of 44 male throwers (throwing record: 80. 50–44. 17 m) participated in the study as subjects. Throwing motions were videotaped on high-speed VTR cameras, and three-dimensional coordinates were calculated using a DLT method. The handle velocity was calculated as the vector products between the anatomical angular velocity vectors of joint and the respective relative displacement vectors from the joint center to handle, by applying a mathematical model. The handle velocity obtained by body movements were projected onto the rotating plane coordinate system. The basic findings were summarized as follows: (1) The handle velocity in the radial direction can be obtained by trunk long-axis rotation, the trunk left lean, the extension of the shoulder joint, the trunk back lean, and translational movement of the body. (2) The handle velocity in the tangential direction can be obtained by the trunk long-axis rotation, trunk twist, horizontal abduction of left shoulder joint and the flexion of shoulder joint.