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.
Joanna Dove Hayes is an American hurdler, who won the gold medal in the 100 metres hurdles at the 2004 Summer Olympics.
Lee McConnell is a retired Scottish athlete, who competed in the 400 metres and 400 metres hurdles having started her career as a high jumper. She is a three-time Olympian who represented Great Britain in 2004, 2008 and 2012. With 12 medals from major championships, McConnell is the third most decorated Scottish track and field athlete of all-time. She was voted Scottish Athlete of the Year in 2002, 2003 and 2007.
Natalya Nikolayevna Antyukh is a Russian sprinter who specializes in the 400 metres and 400 metres hurdles. She won the bronze medal in the 400 metres and a silver for the 4 × 400 m relay at the 2004 Summer Olympics in Athens.
Zuzana Hejnová is a retired Czech athlete who specialised in the 400 metres hurdles. She won the silver medal in the event at the 2012 London Olympics. Hejnová is a two-time World Champion, having claimed titles at the 2013 and 2015 World Championships in Athletics. She won bronze at the 2012 European Championships and silver for the 400 metres at the 2017 European Indoor Championships.
Nataliya Pyhyda is a Ukrainian track and field sprinter who specializes in the 200 and 400 metres. Her personal best times are 22.82 seconds (2008) and 50.62 seconds (2015), respectively.
Antonina Yefremova is a Ukrainian sprinter who specializes in the 400 metres. Yefremova received a two-year ban in 2012 for using testosterone at the 2011 World Athletics Championships.
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.
Anna Kiełbasińska is a Polish sprinter who competed occasionally also in hurdling events. She won the bronze medal in the 400 metres as well as silver medals in the 4 x 100 m and 4 x 400 m relays at the 2022 European Championships. Kiełbasińska earned bronze for the 400 m at the 2023 European Indoor Championships. She won several major medals as part of Polish 4 x 400 m relay teams and also individual medals at European Under-20 and U23 Championships.
Emily Diamond is a British track and field athlete, who competes in the 200 metres and 400 metres. Diamond came to prominence in her breakout season of 2016 when, following her first win at the British Championships over the 400 metres distance, she collected a gold medal in the 4 x 400 metres relay at the 2016 European Athletics Championships as part of the Great Britain team, followed by a bronze in the same discipline at the 2016 Summer Olympics.
Léa Sprunger is a former Swiss track and field athlete. Originally a heptathlete like her older sister Ellen, she began concentrating on the 200 metres and 400 metres in 2011, and then on the 400 metres hurdles from 2015. Her best times in the 400m and 400m hurdles of 50.52 s (2018) and 54.06 s (2019) are the Swiss records. She finished fifth in the 400m hurdles final at the 2017 World Championships, and went on to win the gold medal in the 400m hurdles at the 2018 European Championships.
Dalilah Muhammad is an American track and field athlete who specializes in the 400 meters hurdles. She is the 2016 Rio Olympics champion and 2020 Tokyo Olympics silver medalist, becoming at the latter the second-fastest woman of all time in the event with her personal best of 51.58 seconds. Muhammad was second at both the 2013 and 2017 World Championships to take her first gold in 2019, setting the former world record of 52.16 s. She was the second female 400 m hurdler in history, after Sally Gunnell, to have won the Olympic, World titles and broken the world record. At both the 2019 World Championships and Tokyo Games, she also took gold as part of women's 4 × 400 metres relay team.
Sage Watson is a Canadian athlete specializing in the 400 metres hurdles. Competing internationally for Canada, she is the reigning Pan American champion in the 400 m hurdles, having also won Pan American medals in 2015 and 2019 as part of Canada's relay team.
Nazret Weldu Gebrehiwet is a female long-distance runner from Eritrea. She competed in the 10,000 metres at the 2015 World Championships in Beijing finishing 24th. In 2019, she competed in the senior women's race at the 2019 IAAF World Cross Country Championships held in Aarhus, Denmark. She finished in 27th place.
Raevyn Rogers is an American middle-distance athlete. She won a bronze medal in the 800 meters at the 2020 Tokyo Olympics, becoming the fourth fastest woman in U.S. history in the event. At the 2019 World Championships, Rogers came from seventh with 100m remaining in the race to place silver over USA teammate Ajeé Wilson in bronze. She earned a world indoor title as a member of national 4x400 m relay squad that took gold at the 2018 World Indoor Championships.
Raphaela Boaheng Lukudo is an Italian sprinter specialized in the 400 m, who won four medals at international senior level with Italian national track relay team of the 4×400 m relay.
Aminatou Seyni is a Nigerien track and field sprinter.
Lieke Klaver is a Dutch track and field athlete who specializes in sprint races. She finished fourth in the 400 metres at the 2022 World Athletics Championships. Klaver won the silver medal for the event at the 2023 European Indoor Championships. She earned five major medals as part of Dutch 4 × 400 m relays, either women's or mixed, including silver for the mixed relay at the 2022 World Championships.
Anna Cockrell is an American track and field athlete competing in sprinting and hurdling. She is a two-time medalist at the 2019 Pan American Games in Lima, Peru and she represented the United States at the 2020 Summer Olympics in Tokyo, Japan.
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