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
100 metres hurdles run. From 1926 until 1968 on only the 80 m distance was run. For the 80 m race women had to clear eight hurdles placed at a distance of 8 metres from each other and a height of 76.2 cm. Just like with the men's races, until 1935 no more than three hurdles could be knocked over (or the runner was disqualified) and records were only officially registered if the runner had cleared all her hurdles clean. In 1935, this rule was abandoned, and L-shaped hurdles were introduced that fell over forward easily and greatly reduced the risk of injury