400 metres hurdles to 400 metres, or one lap of the stadium, and the number of hurdles was reduced to ten. The official height of the hurdles was set to 91.4 cm (3 feet) for men and 76.20 cm (2 ft, 6 inches) for women. The hurdles were now placed on the course with a run-up to the first hurdle of 45 metres, a distance between the hurdles of 35 metres each, and a home stretch from the last hurdle to the finish line of 40 metres. The first documented 400 m hurdles race for women took place in 1971. The International Association
400 metres hurdles injury, somewhat more lightweight constructions were introduced in 1895 that runners could push over. However, until 1935 runners were disqualified if they pushed over more than three hurdles in a race and records were only officially accepted if the runner in question had cleared all hurdles clean and left them all standing. The 400 m hurdles became an Olympic event at the 1900 Summer Olympics in Paris, France. At the same time, the race was standardized so that virtually identical races could be held and the finish times compared to each other. As a result, the official distance was fixed