上肢・体幹の関節連動運動にみられる短距離クロール泳選手の特徴

抄録

Swimming techniques require a fine coordination of various joints to maximize performance and reduce the risk of injury. A large number of variables are necessary to describe the coordination of multiple joints during swimming strokes. Since joints move in harmony with other joints during swimming, it should be possible to describe the coordination of multiple joint motions with a fewer characteristic variables. The purpose of the study was to find the characteristic variables to describe the coordination of multiple joint motions of front-crawl sprint swimmers. Twenty-four members of collegiate swimming team were asked to swim a front-crawl technique with their maximal effort in a 25m course. An electromagnetic tracking device was used to record the joint angles in three-dimensions at 240 Hz. Three stroke cycles were extracted for each swimmer and the total of 72 stroke cycles were analyzed. Sixteen variables including the joint angles of elbow, shoulder complex and torso were calculated for each stroke cycles. A principal component analysis was used to simplify the variables of joint angles for each stroke cycles. The scores of principal components were compared between the stroke cycles performed by the front-crawl sprint swimmers and the others. Results showed that 6 principal components account for 77% of the variance. Front-crawl sprint swimmers showed a smaller glenohumeral joint elevation angle, less rotation range of the upper limb and torso lateral tilt mainly in one side during the pull phase of stroke cycles.