The400 metres hurdles is atrack and fieldhurdling event. The event has been on theOlympicathletics programme since1900 for men and since1984 for women.

Athletics 400 metres hurdles
Women's 400m hurdles
World records
Men	Karsten Warholm 45.94 (2021)
Women	Sydney McLaughlin-Levrone 50.37 (2024)
Olympic records
Men	Karsten Warholm 45.94 (2021)
Women	Sydney McLaughlin-Levrone 50.37 (2024)
World Championship records
Men	Alison dos Santos 46.29 (2022)
Women	Sydney McLaughlin-Levrone 50.68 (2022)

On a standard outdoor track, 400 metres is the length of the inside lane, once around the stadium. Runners stay in their lanes the entire way after starting out of the blocks and must clear tenhurdles that are evenly spaced around the track. The hurdles are positioned and weighted so that they fall forward if bumped into with sufficient force, to prevent injury to the runners. Although there is no longer any penalty for knocking hurdles over, runners prefer to clear them cleanly, as touching them during the race slows runners down.

The current men's and women'sworld record holders areKarsten Warholm with 45.94 seconds andSydney McLaughlin-Levrone with 50.37 seconds. Compared to the400 metres run, the hurdles race takes the men about three seconds longer and the women four seconds longer. Men clear hurdles that are 36 inches (91.4 cm) high, while women negotiate 30 inches (76.2 cm) barriers.

The 400 m hurdles was held for both sexes at the inauguralIAAF World Championships in Athletics. The first championship for women came at the1980 World Championships in Athletics – being held as a one-off due to the lack of a race at the1980 Summer Olympics.

The first awards in a men's 400 m hurdles race were given in 1860 when a race was held inOxford, England, over a course of 440 yards (402.336 m). While running the course, participants had to clear twelve wooden hurdles, over 100 centimetres tall, that had been spaced in even intervals.

To reduce the risk of 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 the1900 Summer Olympics inParis, France. At the same time, the race was standardized; thus, virtually identical races could be held and the finish times compared to one other. As a result, the official distance was fixed 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 36 inches (91.4 cm). The hurdles are now placed on the course with a run-up to the first hurdle of 45 metres, distance between the hurdles of 35 metres each, and home stretch from the last hurdle to finish line of 40 metres.

The first documented 400 m hurdles race for women took place in 1971. In 1974, the International Amateur Athletics Federation (IAAF), now known asWorld Athletics, introduced the event officially as a discipline, with hurdles at the lower height of 30 inches (76.2 cm). The women's race was not run at theOlympics until the1984 Summer Games inLos Angeles where it was first staged with the first Men's World Champion having been crowned the year before at theinauguralWorld Athletics Championships. A special edition of the Women's 400m Hurdles took place in the1980 IAAF World Championships in Athletics in response to the Women's 400m Hurdles not being included at the boycotted1980 Summer Olympics inMoscow, andLiberty Bell Classic.

Many athletic commentators and officials have often brought up the idea of lifting the height of the women's 400 m hurdles to incorporate a greater requirement of hurdling skill. This is a view held by German athletic coachNorbert Stein, "All this means that the women's hurdles for specialists, who are the target group to be dealt with in this discussion, is considerably depreciated in skill demands when compared to the men's hurdles. It should not be possible in the women's hurdles that the winner is an athlete whose performance in the flat sprint is demonstrably excellent but whose technique of hurdling is only moderate and whose anthropometric characteristics are not optimal. This was the case at theWorld Championships in Seville and the same problem can often be seen at international and national meetings."^{[citation needed]}

In terms of technique and endurance, the 400-metre hurdles is arguably the most demanding event in the sprints and hurdles group.^{[1]: 4169 [2]: 9} Athletes must be able to run a fast 400-metre flat time, maintain a good hurdling technique, and have a unique awareness of stride pattern between hurdles.^[2]: 9 The ideal time difference between an athlete's 400 time and their 400 hurdles time should be between 1.5 and 3 seconds. This variation depends on the specific qualities of the athlete. At the professional level, the women's hurdles are smaller (76cm) than the men's (91cm) which usually makes the 400-400hs average time difference smaller for female athletes. In 2024, the two fastest 400 hurdlers in the world (Sydney McLaughlin-Levrone and Femke Bol) are also two of the fastest women in the open 400, based on their relay split compared to other athletes. To be able to maintain a good hurdling technique throughout the race it is important to work on step patterns. The number of steps an athlete takes during a 400 hurdles is called rhythm. Most 400 hurdlers know how many steps they are going to take in between each hurdle, starting from the block. The distance between the block and the first hurdle is 45 meters, which allows the fastest women to take 21 to 23 steps, while the fastest men can get down to 19 or 20. After the first one, the hurdles are 35 meters apart, and the tenth one is placed at 40 meters from the finish line. The internal steps from hurdle two to hurdle ten vary depending on the athlete's abilities, speed, technique, and personal preferences. The most skilled athletes can change their rhythm depending on how fast they need, or want, to run. For example, Karsten Warholm ran 13 steps up to hurdle seven, then decided to switch to 15 steps for the last three hurdles at the Paris Olympics, because he is more comfortable going over hurdles with his dominant leg. An even number of steps in between the hurdles implies alternating which leg goes over it first (lead leg), while an uneven number of steps allows for going over the hurdles with the same leg. Furthermore, athletes must possessanaerobic endurance over the final 150 to 100 metres of the race as, at this point,lactate (theconjugate base of lactic acid) will accumulate in the body fromanaerobic glycolysis.^[3]: 43

When preparing to hurdle, the blocks should be set so that the athlete arrives at the first hurdle leading on the desired leg without inserting a stutter step. A stutter step is when the runner has to chop his or her stride down to arrive on the "correct" leg for take off. Throughout the race, any adjustments to stride length stride speed should be made several strides out from the hurdle because a stutter or being too far from the hurdle at takeoff will result in loss of momentum and speed.

At the beginning of the take-off, the knee must be driven toward the hurdle and the foot then extended. The leg position when extended must be stretched out, in a position of a split. The knee should be slightly bent when crossing the hurdle. Unless an athlete's body has great flexibility, the knee must be slightly bent to allow a forward body lean. Unlike the110m hurdles, a significant forward body lean is not that necessary due to the hurdles being lower. However, the trail leg must be kept bent and short to provide a quick lever action allowing a fast hurdle clearance. The knee should pull through under the armpit and should not be flat across the top of the hurdle.

It is also important that the hurdler does not reach out on the last stride before the hurdle as this will result in a longer bound being made to clear the hurdle. This will also result in a loss of momentum if the foot lands well in front of the center of gravity.

Using a left lead leg on the bends allows the hurdler to run closer to the inside of the lane and cover a shorter distance. Additionally, if the left leg is used for the lead, then the athlete's upper body can be leaned to the left, making it easier to bring the trail leg through. Additionally, an athlete hurdling with a right leg lead around the bends must take care that they do not inadvertently trail their foot or toe around the hurdle rather than passing over the top, which would lead to a disqualification from the race. Depending on the height and strength of the athlete, men work toward a stride pattern of 13 to 15 steps between each hurdle, and women work toward a stride pattern of 15 to 17. This does not include the landing step from the previous hurdle.Edwin Moses was the first man to keep 13 strides throughout an entire race. Weaker athletes will typically hold a longer step pattern throughout the race so that they do not bound or reach with each step, which also results in a loss of speed. These patterns are ideal because it allows the hurdler to take off from their predominant leg throughout the race without switching legs. However, fatigue from the race will knock athletes off their stride pattern and force runners to switch legs. At an early age, many coaches train their athletes to hurdle with both legs. This is a useful skill to learn since as a runner tires, their stride length may decrease, resulting in the need either to add a stutter stride, or to take a hurdle on the other leg. Even though some athletes prefer using their dominant leg as lead, every professional knows how to go over hurdles with both legs. Some athletes have started choosing an even rhythm (Sydney McLaughlin-Levrone does 14 steps for most of her race).

• Updated 14 July 2024.^[4][5]

• Correct as of August 2024.^[6][7]

• Correct as of May 2025.^[33]

The following athletes have had their personal best annulled due to doping offences:

• Men
  • First officialIAAF world record: 55.0 seconds,Charles Bacon (USA), 1908
  • First under 54 seconds: 53.8 seconds,Sten Pettersson (SWE), 1925
  • First under 53 seconds: 52.6 seconds,John Gibson (USA), 1927
  • First under 52 seconds: 51.7 seconds,Bob Tisdall (IRL), 1932
  • First under 51 seconds: 50.6 seconds,Glenn Hardin (USA), 1934
  • First under 50 seconds: 49.5 seconds,Glenn Davis (USA), 1956
  • First under 49 seconds: 48.8 seconds,Geoff Vanderstock (USA), 1968
  • First under 48 seconds: 47.82 seconds,John Akii-Bua (UGA), 1972
  • First under 47 seconds: 46.78 seconds,Kevin Young (USA), 1992
  • First under 46 seconds: 45.94 seconds,Karsten Warholm (NOR), 2021^[56]
• Women
  • First official world record: 56.51 seconds,Krystyna Kacperczyk (POL), 1974
  • First under 56 seconds: 55.74 seconds,Tatyana Storozheva (URS), 1977
  • First under 55 seconds: 54.89 seconds,Tatyana Zelentsova (URS), 1978
  • First under 54 seconds: 53.58 seconds,Margarita Ponomaryova (URS), 1984
  • First under 53 seconds: 52.94 seconds,Marina Stepanova (URS), 1986
  • First under 52 seconds: 51.90 seconds,Sydney McLaughlin-Levrone (USA), 2021
  • First under 51 seconds: 50.68 seconds,Sydney McLaughlin-Levrone (USA), 2022

American athleteGlenn Davis had a prodigious start to his hurdling career, running his first race in April 1956 in 54.4 s. Two months later, he ran a new world record with 49.5 s and later that year he won the 400 m hurdles at the Olympics, and was also the first to repeat that feat in 1960.

In terms of success and longevity in competition,Edwin Moses' record is significant: he won 122 races in a row between 1977 and 1987 plus two gold medals, at the1976 Summer Olympics in Montréal and the1984 Summer Olympics in Los Angeles. He was undefeated for exactly nine years nine months and nine days, from 26 August 1977 until 4 June 1987. He finished third in the1988 Olympic final, the last race of his career. He also held the world record for sixteen years from when he first broke it at the Olympics on 25 July 1976 until it was finally broken byKevin Young at the1992 Summer Olympics in Barcelona.

• Olympic Games & World Championships victories
  • Edwin Moses (USA), Olympic 1976, 1984, World 1983, 1987
  • Felix Sanchez (DOM), Olympic 2004, 2012, World 2001, 2003
  • Karsten Warholm (NOR), Olympic 2020, World 2017, 2019, 2023
  • Kerron Clement (USA), Olympic 2016, World 2007, 2009
  • Sally Gunnell (GBR), Olympic 1992, World 1993
  • Kevin Young (USA), Olympic 1992, World 1993
  • Derrick Adkins (USA), Olympic 1996, World 1995
  • Melaine Walker (JAM), Olympic 2008, World 2009
  • Lashinda Demus (USA), Olympic 2012, World 2011
  • Dalilah Muhammad (USA), Olympic 2016, World 2019
  • Sydney McLaughlin-Levrone (USA) Olympic 2020, 2024, World 2022
• Two Olympic victories:
  • Glenn Davis (USA), 1956 and 1960
  • Edwin Moses (USA), 1976 and 1984 (also bronze in 1988)
  • Angelo Taylor (USA), 2000 and 2008
  • Félix Sánchez (DOM), 2004 and 2012
  • Sydney McLaughlin-Levrone (USA), 2020 and 2024
• Three World Championships:
  • Karsten Warholm (NOR), 2017, 2019 and 2023
• Two World Championships:
  • Edwin Moses (USA), 1983 and 1987
  • Félix Sánchez (DOM), 2001 and 2003 (won silver in 2007)
  • Kerron Clement (USA), 2007 and 2009
  • Nezha Bidouane (MAR), 1997 and 2001 (won silver in 1999)
  • Jana Pittman (AUS), 2003 and 2007
  • Zuzana Hejnová (CZE), 2013 and 2015

* Note:Edwin Moses,Kevin Young andKarsten Warholm are the only male 400 m hurdlers to have been Olympic Champion, World Champion, and broken theWorld Record.
* Note:Sally Gunnell,Dalilah Muhammad andSydney McLaughlin-Levrone are the only female 400 m hurdlers to have been Olympic Champion, World Champion, and broken theWorld Record.

• The officialWorld Athletics Championships began in 1983 as the IAAF World Championships in Athletics, but in 1980, the women's 3000 metres and 400 metres hurdles events had a World Championship competition inSittard, Netherlands. This was due to these events not yet being on the Olympic program (the same had happened in 1976 for the men's 50 km walk).^[57]

• Updated 6 July 2024.^[58]

Equal or superior to 48.00 s:

• Updated 8 August 2024.^[59]

Equal or superior to 54.00 s: