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.
Jeremy Matthew Wariner is a retired American track athlete specializing in the 400 meters. He has won four Olympic medals and six World Championships medals. He is the fourth fastest competitor in the history of the 400 m event with a personal best of 43.45 seconds, behind Wayde van Niekerk, Michael Johnson and Butch Reynolds and the fifth fastest all-time mark when he set it in 2007.
The 4 × 400 metres relay or long relay is an athletics track event in which teams consist of four runners who each complete 400 metres or one lap. It is traditionally the final event of a track meet. At top class events, the first leg and the first bend of the second leg are run in lanes. Start lines are thus staggered over a greater distance than in an individual 400 metres race; the runners then typically move to the inside of the track. The slightly longer 4 × 440 yards relay, on an Imperial distance, was a formerly run British Commonwealth and American event, until metrication was completed in the 1970s.
Leslie Djhone is a French track and field athlete who competes in the 400 metres and 4 x 400 metres relay.
Marc Raquil is a French runner of Martiniquais origin who competes in the 400 metres and 4x400m relay. He won the 4x400m relay gold medal and the 400m silver medal at the 2003 World Championships. In 2004, his 4x400m relay team was retroactively awarded gold medals after the United States 4x400m relay team was stripped of its gold medals due to the failed drug tests of two members of the relay. Since Jerome Young had also finished first in the 400m at the 2003 World Championships, the failed drug test also resulted in Raquil being retroactively awarded a silver medal in the 400m. Raquil has also won three gold medals and one bronze medal at the European Indoor and Outdoor Championships.
Clive Terrelonge is a Jamaican former track and field athlete and coach. University of Connecticut. Before coaching, he was an accomplished collegiate and professional athlete who specialized in the 800m and 400m.
Rabah Mahhamed Yousif Bkheit is a Sudanese-born British track and field athlete, who initially competed for Sudan before obtaining British citizenship.
Melaine Walker O.D is a Jamaican 400 metres hurdler. She was born in Kingston. Walker is the former Olympic 400 m hurdles champion. She held the Olympic record of 52.64, set at the 2008 Beijing Olympics, and her time of 52.42 seconds at the 2009 World Championships in Berlin was the second fastest time in history at the time.
Kevin Borlée is a Belgian sprinter, who specializes in the 400 metres. He is a member of the Borlée family.
Michael Walter Mathieu is a retired Bahamian sprinter hailing from Freeport, Grand Bahama who specialized in the 200 metres and 400 metres. He was part of the Bahamian silver medal-winning team in the men's 4×400 metres relay at the 2008 Beijing Olympics, running second leg and recording a 44.0 split, and the gold medal-winning team at the 2012 Summer Olympics. He was also a part of second place relay team at the 2007 World Championships. He won the bronze medal in the 4x400 metres relay in the 2016 Summer Olympics.
Jonathan Borlée is a Belgian sprinter, who specializes in the 400 metres. He is a member of the Borlée family.
Arman "Gino" Hall is an American sprinter specializing in the 400m. He is a World and Olympic gold medalist as a member of USA's 2014 and 2016 4 × 400 m relay teams.
Francena Lynette McCorory is a retired American track and field athlete, known primarily for running the 400 meters. She was the 2011 World bronze medalist in the 400 meters and was a member of the gold medal-winning 2012 and 2016 United States Olympic 4 x 400 m relay teams. She was the IAAF 400 meter Indoor World Champion in 2014. McCorory retired in 2021.
Steven Solomon is an Australian Olympic sprinter. He is a six-time defending Australian 400 metres champion.
Tony McQuay is an American track and field athlete who specializes in the 400 meters. He is a member of the 2012 and 2016 United States Olympic teams, winning a silver medal in the 4 × 400 m relay in 2012 and a gold in the same event in 2016. He is also a two time World Champion in this event.
Afia Neliah Charles is a sprinter from Antigua and Barbuda who specializes in the 400 metre dash.
Ashley Spencer is an American track and field athlete who competes in the 400 metres and the 400 metres hurdles. In the 400m hurdles, she is the 2016 Olympic bronze medalist. In the 400m, she is the 2012 World Junior Champion and the 2016 World Indoor silver medalist. She is coached by 1996 Olympic bronze medalist Tonya Buford-Bailey.
Michael Arthur Norman Jr. is an American sprinter. He previously held the world best time in the indoor 400 meters at 44.52 seconds. Outdoors, his 43.45, set at the 2019 Mt. SAC Relays is tied as the #4 on the all time list. In 2016, he became the world junior champion in both the 200 meters and 4×100 meter relay. In 2022, he became the world champion in both the 400 meters and 4x400 meter relay.
Courtney Okolo is an American track and field sprinter who usually competes in the 400 metres. She starred at Carrollton (Texas) Newman Smith High School where she won multiple individual state championships.
Elija Godwin is an American athlete who specialises in the 400 metres.
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