抄録
The purpose of this study was to compare the direction of kick movement during front crawl at different swimming velocities. Eight competitive national-level male swimmers with a specialty in front crawl participated in this study. They performed the front crawl at two different swimming velocities-maximum velocity (V100%) and 80% of the velocity of the their respective best times for a 100 m front crawl (V80%). The trials were recorded with four underwater digital video cameras. One stroke cycle, between two consecutive right-hand entries, was analyzed. Downbeat kick movement was quantified using an index of kick pattern (IKP). The following results were observed.
1) There was no significant difference in the vertical width of the kick movement between V100% and V80%.
2) There was a significant difference in the horizontal width of the kick movement between V100% and V80% because of an increase in the hip roll angle.
3) The IKP was dependent on the horizontal width.
4) The kick movement was confirmed to have an overall vertical direction at V100%.
5) The kick movement was confirmed to have an obliquely downward direction at V80%. These results indicated different directions of the kick movement during front crawl at different swimming velocities.
