@article{oai:nagoya.repo.nii.ac.jp:02005149, author = {池上, 久子 and IKEGAMI, Hisako and 池上, 康男 and IKEGAMI, Yasuo and 桜井, 伸二 and SAKURAI, Shinji and 岡本, 敦 and OKAMOTO, Atsushi and 吉岡, 伸彦 and YOSHIOKA, Nobuhiko}, issue = {1}, journal = {総合保健体育科学, Nagoya Journal of Health, Physical Fitness & Sports}, month = {Mar}, note = {In recent figure skating competitions, jumps have become much more important in evalualion of a competitor's performance. World-class top-level skaters always perform various kinds of jumps with multiple rotaiions of the body. In this study triple Axel jumps performed by junior class figure skaters were analyzed kinematically by means of video recordings. Two electrically synchronized high-speed video cameras (HSV-500 C3, Nac Inc.) located in the stand were used to record the movements of a skater's body during jumps. The recording speed was 250 fields per second. Three-dimensional coordinates of reference points in the skater's body were calculated from digitized data by means of direct linear transformation method (DLT). Three-dimensional coordinales of the center of gravity of the skater's body (C.G.) were calculated and using C.G. data, important kinematical parameters characterizing the jump were obtained. Jumping height was defined as vertical displacement or C.G. between take off and top of jump. Successful and unsuccessful triple Axel jumps performed by three junior class skaters were selected for analysis. Furthermore, the duration of a flight (flight time) of other kinds of jumps were also calculated. These kinematical analyses revealed the following results. 1. When a successful and unsuccessful jumps were compared, there observed no significant differences in jumping height, flight time and rotations of the body for triple Axel jump. 2. Rotations of the body in the air in the successful jumps were 2.6 rev, and there observed no significant differences in both successful and unsuccessful jumps. The bodies rotated 0.4 rev before take off, 2.6 rev in the air and 0.5 rev after landing, respectively. 3. Durations or flights of a triple Axel jumps by three skaters were 604 msec (MI), 548 msec (MO) and 556 msec (NA). respectively. 4. Estimated flight times for three complete rotations of the body in the air showed increases of 88 msec(MI), 116 msec(MO) and 105 msec(NA) in comparison with measured durations of flights. 5. From the results of the study, one of the essential factors for a successful triple Axel jump was the enough duration of a flight, which can be achieved by enough vertical velocity of C.G. at take off. The longer duration of the flight would make it possible to perform more accurate and stable jumps in more difficult conditions such as in triple Axel jumps}, pages = {17--26}, title = {フィギュアスケートジャンプのバイオメカニクス : 女子選手のトリプルアクセルジャンプの運動学的研究}, volume = {27}, year = {2004} }