Introduction: Budo had become a compulsory subject in a course of study of Japanese junior high school in 2014. Therefore, most of junior high school students have a possibility to learn judo in physical education class since then. It is very magnificent for us, Japanese people, to experience traditional Budo. On the other hand, we can say that the population of beginner has increased because of its changes in compulsorization. Specifically, external head injury during judo is focusing. Therefore, the purpose of this study was to identify the maximal angular velocity(AV) and angular acceleration(AA) acted on head during Ushiro-ukemi(UU), Yoko-ukemi(YU), and ukemi for Ukemi of Osotogari(OU). It might be very important knowledge for practicing safely in a coaching scene. Methods: Six collegiate judo wrestlers, who experienced judo over ten years served as subjects. Subjects did UU and YU. Moreover, they did ukemi after there were thrown with OU. Four retro-reflective markers were put on the subject`s head surrounding during the experiment. The coordinate values were measured using 3D motion capture system (Vicon MX,Oxford). A coordinate system of a head was defined from the marker loaded on a head. And the AV and an AA were calculated. The maximum of an AV and the AA was presumed as the impact, which acts on a head. Results: Maximum resultant AV during UU, YU, and OU were 347±80.3deg/s, 318±29.9deg/s..and 394±82.3deg/s respectively. Significant difference was seen among maximum velocities during UU and YU. And No significant difference was seen between YO and OU. Then, maximum resultant AA were. 5011±983.3deg/s2, 7028±2324.6deg/s2, and 7990±3349.8deg/s2, Significant difference was seen between UU and YU. And No significant difference was seen between YO and OU. Discussion: AV during OU indicated higher value compared with UU, though angular velocities didn`t differ among UU and OU. Hitosugi et al (2014) buried accelerometer in dummy doll`s head and reported the higher acceleration values during ukemi compared with the acceleration of present study. Therefore, it can be said that the originality of present study was to measure acceleration of head during ukemi in vivo, though the reported values were different from the reported values in present studies. As a result of this study, the acceleration during OU was significantly higher value compared with UU. In the course of study of in physical education in Japanese junior high school, OU was acquired immediately after UU. However, the result of present study indicate that asotogari should be taught after students acquire YU because of avoiding heavy head injure caused by OU.
© Copyright 2016 21st Annual Congress of the European College of Sport Science (ECSS), Vienna, 6. -9. July 2016. Veröffentlicht von University of Vienna. Alle Rechte vorbehalten. / Übersetzt mit https://www.DeepL.com/Translator