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.
Veronica Campbell Brown CD is a retired Jamaican track and field sprinter, who specialized in the 100 and 200 meters. An eight-time Olympic medalist, she is the second of three women in history to win two consecutive Olympic 200 m events, after Bärbel Wöckel of Germany at the 1976 and 1980 Olympics and fellow countrywoman Elaine Thompson-Herah at the 2016 and 2020 Olympics. Campbell Brown is one of only nine athletes to win world championships at the youth, junior, and senior level of an athletic event.
The World Athletics U20 Championships is a biennial world championships for the sport of athletics organised by the World Athletics, contested by athletes in the under-20 athletics age category (19 years old or younger on 31 December in the year of the competition.
Angela Williams is an American athlete. Williams attended the University of Southern California, graduating in 2002. She won the Honda Sports Award as the nation's best female track and field competitor in 2002, which qualified her as a nominee for the Honda-Broderick Cup, awarded to the best overall female collegiate athlete in 12 sports. She was named the winner of that award also in 2002.
Blessing Oghnewresem Okagbare-Otegheri is a former Nigerian track and field athlete who specialized in long jump and sprints. She is an Olympic and World Championships medallist in the long jump and a world medalist in the 200 metres. Okagbare also holds the women's 100 metres Commonwealth Games record at 10.85 seconds. She is currently serving a 10-year ban for breaching multiple World Athletics anti-doping rules. Her ban expires on 30 July 2032.
Mokgadi Caster Semenya OIB is a South African middle-distance runner and winner of two Olympic gold medals and three World Championships in the women's 800 metres. She first won gold at the World Championships in 2009 and went on to win at the 2016 Olympics and the 2017 World Championships, where she also won a bronze medal in the 1500 metres. After the doping disqualification of Mariya Savinova, she was also awarded gold medals for the 2011 World Championships and the 2012 Olympics.
Lidiane Lopes is a Cape Verdean sprinter who specialises in the 100 metres and 200 metres. She is the current Cape Verdean record holder in the 100-metre sprint. Lopes has competed at both the 2012 and 2016 Summer Olympics. At both Olympics, she competed in the 100 metres. She has also competed in a World Championships, a World Junior Championships, a World Youth Championships, a Jeux de la Francophonie, a Lusophony Games, an African Games, and an Ibero-American Athletics Championships.
The 2019 IAAF World Athletics Championships was the seventeenth edition of the biennial, global athletics competition organised by the International Association of Athletics Federations (IAAF), since renamed World Athletics. It was held between 27 September and 6 October 2019 in Doha, Qatar, at the renovated multi-purpose Khalifa International Stadium, but reduced to 21,000 available seats. 1,772 athletes from 206 teams competed in 49 athletics events over the ten-day competition, comprising 24 events each for men and women, plus a mixed relay. There were 43 track and field events, 4 racewalking events, and 2 marathon road running events. The racewalking and marathon events were held in Doha Corniche.
Regine Tugade-Watson is a Guamanian sprinter. She competed in the women's 100 metres event at the 2015 World Championships in Athletics in Beijing, China, as well as the girl's 200 m event at the 2015 World Youth Championships in Cali, Colombia. She competed in the women's 100 m preliminary round of the 2016 Summer Olympics. Tugade finished third place in her heat but did not progress further. She also competed in her second World Championships in 2017, competing in the 200 m. She holds seven Guamanian national records in athletics. In July 2021 she was a flag bearer in the Parade of Nations at the Tokyo Olympics opening ceremony.
Kendall Ellis is an American sprinter. Ellis won gold in the 4x400 m relay and bronze in the Mixed 4x400 metres at the Tokyo Olympics. She competed in the 400 meters at the 2017 and 2019 World Championships, winning gold medals as a part of prelim 4×400 m relays. As a junior, Ellis took gold in the 4×400 m relay and bronze in the 400 meters at the 2015 Pan American Junior Championships.
Norway competed at the 2019 World Athletics Championships in Doha, Qatar, from 27 September to 6 October 2019.
Teahna Daniels is an American athlete competing in sprinting events. Representing the United States at the 2019 World Athletics Championships, she placed seventh in the women's 100 metres.
Aminatou Seyni is a Nigerien track and field sprinter.
Hawi Feysa is an Ethiopian track and field athlete who specializes in long-distance running.
Natalliah Whyte is a Jamaican track and field athlete who specializes in sprint. She represented the Jamaica at the 2019 World Athletics Championships, winning a gold medal in 4 × 100 metres relay.
Mercy Ntia-Obong is a Nigerian athlete. She competed in the women's 4 × 100 metres relay event at the 2019 World Athletics Championships.
Ida Kathrine Karstoft is a Danish athlete. She competed in the women's 4 × 100 metres relay event at the 2019 World Athletics Championships. Karstoft won the bronze medal in the 200 metres at the 2022 European Championships.
Chanice Porter is a Jamaican track and field athlete who specializes in long jump. She represented Jamaica at the 2019 World Athletics Championships, competing in women's long jump.
Paulien Couckuyt is a Belgian track and field athlete who specializes in middle-distance running and 400 metres hurdles. She represented Belgium at the 2019 World Athletics Championships, competing in women's 400 metres hurdles and women's 4 × 400 metres relay.
Mauricia Prieto is a Trinidad and Tobago track and field athlete who specializes in sprint. She placed fourth in women's 4 × 100 metres relay with the Trinidadian team at the 2019 Pan American Games, and also competed in women's 200 metres. Representing Trinidad and Tobago at the 2019 World Athletics Championships, she competed in women's 200 metres and women's 4 × 100 metres relay. In the 200 metres event she did not advance to compete in the semi-finals.
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