2020年度 日本陸上競技学会 学会賞として
The aim of this study was to create an acceleration index as an acceleration indicator in sprinting and to investigate the kinematic factors for determining faster sprint acceleration using biomechanical methods. The subjects were 26 students (age: 19.9 ± 1.2 years, height: 1.73 ± 0.05 m, weight: 67.4 ± 7.1 kg, ％ fat: 10.6％ ± 2.3％) who belonged to a university sports club (Athletics sprinting: n = 4, Athletics jumping: n = 4, baseball: n = 3, soccer: n = 3, basketball: n = 3, rugby: n = 4, softball: n = 2, and beach flags: n = 1). The velocity curve at a 60m run was obtained using a laser velocimeter. A velocity curve model was created using the least square method for the obtained velocity curve, and the coefficient was used as the acceleration index. The sprinting motion during acceleration was filmed in an indoor laboratory. The trial was a 20m sprint, and the filming range was from the second to the third step touchdown after starting. Kinematic data were calculated from the obtained images using biomechanical method. The results showed a particularly high correlation between the acceleration index and the contact time, center-of-gravity angle, and angular displacement of hip joint extension during the contact period. These results suggest that subjects with better acceleration at the highest speed grounded their feet in front of their body and kicked the ground for a longer period. In addition, the subjects with better acceleration had a higher workload in hip extension. This suggests the importance of hip extension movement during the contact period.