The 400 metres hurdles is a track and field hurdling event. The event has been on the Olympic athletics programme since 1900 for men and since 1984 for women.
The 400 metres, or 400-meter dash, is a sprint event in track and field competitions. It has been featured in the athletics programme at the Summer Olympics since 1896 for men and since 1964 for women. On a standard outdoor running track, it is one lap around the track. Runners start in staggered positions and race in separate lanes for the entire course. In many countries, athletes previously competed in the 440-yard dash (402.336 m)—which is a quarter of a mile and was referred to as the "quarter-mile"—instead of the 400 m (437.445 yards), though this distance is now obsolete.
Usain St. Leo Bolt is a Jamaican retired sprinter, widely considered to be the greatest sprinter of all time. He is an eight-time Olympic gold medalist and the world record holder in the 100 metres, 200 metres, and 4 × 100 metres relay.
Oscar Leonard Carl Pistorius is a South African former professional sprinter and convicted murderer. He was first convicted of culpable homicide of his then-girlfriend, which was subsequently upgraded to murder upon appeal. Both of his feet were amputated when he was 11 months old as a result of a congenital defect; he was born missing the outside of both feet and both fibulas. Pistorius ran in both nondisabled sprint events and in sprint events for below-knee amputees. He was the 10th athlete to compete at both the Paralympic Games and Olympic Games.
LaShawn Merritt is a retired American track and field athlete who competed in sprinting events, specializing in the 400 metres. He is a former Olympic champion over the distance and his personal best of 43.65 seconds makes him the eleventh fastest of all time.
Paul Biedermann is a German retired competitive swimmer, a 200 and 400 metre freestyle long course world champion. He holds the long course and short course world records in the 200 meters freestyle, and the long course world record in the 400 meters freestyle.
Kirani James is a Grenadian professional sprinter who specializes in the 400 metres. He won the 400 m at the World Championships in 2011, and won the gold medal at the 2012 London Olympics. In the 400 metres, James also won the silver medal at the 2016 Rio Olympics, and bronze medal at the 2020 Tokyo Olympics, thus becoming the first man to earn the full set of three medals in the centennial history of the event. He is Grenada's first Olympic medalist. He holds the Grenadian national record in both the 200 metres and 400 metres.
Sun Yang is a Chinese Olympic and former world-record-holding competitive swimmer. In 2012, Sun became the first Chinese athlete to win an Olympic gold medal in men's swimming. Sun is the first male swimmer in history to earn Olympic and World Championship gold medals at every freestyle distance from 200 to 1500 metres. A three-time Olympic gold medalist and eleven-time world champion, he is the most decorated Chinese swimmer in history. In 2017, NBC Sports described him as "very arguably the greatest freestyle swimmer of all time".
Matteo Galvan is an Italian athlete who specializes in the 200 and 400 metres. His career highlight so far is the 2009 European Indoor Championships, where he placed sixth in the 400 metres and won a gold medal in the relay.
Lalonde Keida Gordon, HBM is a Tobagonian male track and field sprinter who specialises in the 400 metres. He won the bronze medal at the 2012 London Olympics with a personal best of 44.52 seconds. He is the third fastest 400 m runner from his country after Machel Cedenio and Ian Morris.
Luguelín Miguel Santos Aquino is a Dominican sprinter, who specialises in the 400 m. He was the silver medallist in the event at the 2012 London Olympics at the age of nineteen. His personal best is 44.11 seconds.
Shaunae Miller-Uibo is a Bahamian track and field sprinter who competes in the 200 and 400 metres. She is a two-time Olympic champion after winning the women's 400 metres at the 2016 Rio Olympics and again at the 2020 Tokyo Olympics.
Maoulida Darouèche is a Comoran hurdler who specialises in the 400 metres hurdles and who has also competed in the javelin throw. Darouèche competed in the 2012 Summer Olympics and the 2016 Summer Olympics. At both Olympics he competed in the 400 metres hurdles. He has also competed in two World Championships, an African athletics championships and a Jeux de la Francophonie.
Daiya Seto is a Japanese professional swimmer who specializes in individual medley, butterfly, breaststroke, and freestyle events. He holds the world record in the short course 400-metre individual medley and formerly held the world record in the short course 200-metre butterfly. He won the gold medal in the 400-metre individual medley at the 2012, 2014, 2016, 2018, 2021, and 2022 world short course championships, as well as at the 2013, 2015, and 2019 world long course championships.
Yasmani Copello Escobar is a Cuban-born track and field hurdler who represents Turkey internationally. His personal best for the 400 metres hurdles is 47.81 seconds, set in the final of the 2018 European Athletics Championships in Berlin.
Wayde van Niekerk is a South African track and field sprinter who competes in the 200 and 400 metres. In the 400 metres, he is the current world and Olympic record holder, having set the record when he won the event at the 2016 Olympics.
Matthew Hudson-Smith is a British track and field sprinter who specialises in the 400 metres. He holds, as of August 2024, the British and European record, running a personal best of 43.44 seconds for the distance at the 2024 Summer Olympics. He was the 2018 European Champion in 400 metres, and a member of the gold-winning teams in the 4 x 400 metre relay at the 2014 European Athletics Championships, with Great Britain and 2014 Commonwealth Games with England.
Jakub Krzewina is a Polish track and field sprinter who specialises in the 400 metres. A frequent competitor for Poland in the 4×400 metres relay, he has won two medals at the European Athletics Championships and reached the final at the 2016 Summer Olympics. He was also a relay silver medallist with Europe at the 2014 IAAF Continental Cup.
Ned Justeen Azemia is a Seychellois hurdler who specialises in the 400 metres hurdles. He is the current Seychellois record holder in the event. Azemia competed in the 2016 Summer Olympics in Rio de Janeiro in the 400 metres hurdles. He has also competed in two World Junior Championships, an African athletics championships and an African Youth Games. Azemia has also raced over the flat 400 metres distance.
Joseph Millar is a New Zealand sprinter.
Canada 
