2013 Fiscal Year Final Research Report

Mechanics of turns around the longitudinal axis of the whole body.

Research Project

Project/Area Number	23700714
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Multi-year Fund
Research Field	Sports science
Research Institution	The University of Tokyo
Principal Investigator	IMURA Akiko 東京大学, 総合文化研究科, 助教 (30586699)
Project Period (FY)	2011 – 2012
Keywords	バレエ / バイオメカニクス / 逆動力学 / 体幹長軸回りの回転 / 角運動量
Research Abstract	The aim of this study was to investigate the mechanics of pirouette in classic ballet on generating the angular momentum around the vertical axis of the whole body. Five Russian male and ten Japanese female dancers performed pirouette. Motion capture system and force platforms recorded them to analyze by an inverse dynamic method. The male dancers performed four turns and the female dancers performed two turns in one pirouette on average. The angular momentum for all the turns was generated at the beginning of the pirouette by a twisting torque from the floor during the arm rotation in the horizontal plane. Then the female dancers also rotate their upper trunk. To correct this trunk distortion, the hip joint torque of the support leg pulled back the pelvis to the front. Thus the twisting torque has to be exerted only by the arm rotation.To perform many turns by one kick in a pirouette, the dancer adducted both upper arms in the horizontal plane and the pull down the gesture leg.