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
110 metres hurdles instead of being jumped over and with three steps each between the hurdles was first used by the 1900 Olympic champion, Alvin Kraenzlein. The 110 metre hurdles have been an Olympic discipline since 1896. Women ran it occasionally in the 1920s but it never became generally accepted. From 1926 on, women have only run the 80 metre hurdles which was increased to 100 metres starting in 1961 on a trial basis and in 1969 in official competition. In 1900 and 1904, the Olympics also included a 200-metre hurdles race, and the IAAF recognized world records for the 200 metre hurdles