Effect of Downhill Declination on Sprint Kinematics

One form of assisted training is a downhill sprint, which uses a portion of gravity. This study aimed to compare sprinting on multiple downhill and level ground to clarify the parameters related to sprint velocity and differences in movement. The subjects were 17 male university athletics students, made to sprint 50 m on level ground and five downhill slopes (slope=1, 2, 3, 4, and 5°), respectively. The results showed that the sprint velocity were higher than on level ground for downhill sprint at all slopes (1°, 2°, 3°, 4°, and 5°), and even higher than on other slopes at 4° and 5°. In addition, minor changes in sprint kinematics were observed at 1°, 2°, and 3°, while major changes were observed at 4° and 5°. In particular, many joint angle differences were observed between 4° and 5°, suggesting that they were due to gravity-assisted velocity increases on downhill slopes and structural features of the slopes. Therefore, it is clear that downhill has different effects on sprinting depending on the degree of slope.