Abstract: Using mathematical statistics, the paper analyzes the time and speed parameters of the world elite women 400m hurdle athletes to explore the law of the time features and speed changes. The research indicates that the speed from star to the first hurdle and the speed of the home stretch demonstrate a significant negative correlation and the excessive acceleration during the start period constitutes one of the reasons of the hypodynamic sprint. There is a kind of shifting relationship between the maximum speed, the ability to maintain the maximum speed, the stability of speed, the biggest decrease rate of speed and the utilization rate of the maximum speed between hurdles. one of the important technique factors to give a full play to the speed level is to reasonably control the maximum speed during the acceleration period and the maximum speed between hurdles, and to maintain the stability of the speed rhythm during the whole course. There is correlation between the changes of stride frequency and other important speed indexes between hurdles. The changes of stride is he main factor influencing the changes of the speed between hurdles while the ability to maintain stride frequency serves as an important factor to maintain overall speed between hurdles.

Key words: women, 400m hurdles, time between hurdles, speed between hurdles, speed utilization rate