Jerome Young is an American former track and field sprinter who specialized in the 400-meter dash. He won gold medals with the United States 4 × 400-meter relay team at the 2001 World Championships in Athletics and 1997 World Championships in Athletics, but was later stripped of these medals due to doping and was ultimately banned from the sport. He also was the heats runner for the relay team at the 2000 Summer Olympics, where the Americans won gold, but this medal was rescinded as well.
Michael Blackwood is a Jamaican male track and field athlete, who specialized in the 400 meters, his personal best being 44.60 set during his win at the 2002 IAAF World Cup. He was chosen as the Jamaica Sportsman of the Year in 2002, in that same year he was the world number one rank by IAAF in the 400 meters. He is the brother of Catherine Scott who earned a silver medal in the 2000 Sydney Olympic Games. Blackwood won the NAIA national 400 meters title in 1997. He is the winner of Jamaica 400 meters national championships three times. Blackwood holds the Big 12 conference record in the 400 meters since 2000 in the time of 44.69. He is an alumnus of The University of Oklahoma.
Leslie Djhone is a French track and field athlete who competes in the 400 metres and 4 x 400 metres relay.
Marek Plawgo is a Polish athlete. He mainly competes in the 400 meters hurdles, but he also starts in the 400 meters and the 4 x 400 meters relay.
Nicola Clare Sanders is a former British track and field sprinter. She began her career as a 400 metres hurdles specialist before concentrating on the 400 metres from 2006 onwards. Her 400 metres personal best is 49.65 seconds. She holds the British indoor record with 50.02 seconds, which ranks her as the fifth fastest woman of all-time indoors.
Diane Lynn Dixon is an American athlete who competed mainly in the 400 metres. She was born in Brooklyn, New York. She has an Olympic gold medal for running with the American 4x400 meters relay team at the 1984 Olympics, running in the preliminary rounds.
LaShawn Merritt is an American track and field athlete who competes 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 ninth fastest of all time.
Seiji Inagakiis a retired Japanese athlete who specialized in the 400 metres hurdles.
Hiroyuki Hayashi is a retired Japanese sprinter who specializes in the 400 metres.
Asami Chiba, or Tanno, is a Japanese sprinter who specialises in the 400 metres. She is the Japanese record holder in the event, and has also broken the national record in the 4×400 metres relay on multiple occasions. She is a member of Natureal Athlete Club in Japan and is coached by Kazuhisa Kawamoto.
Adam Piotr Kszczot is a retired Polish middle-distance runner who specialised in the 800 metres. His achievements include silver medals at the 2015 and 2017 World Championships in Athletics, gold at the 2018 World Indoor Championships as well as silver and bronze at the 2014 and 2010 World Indoor Championships respectively. Kszczot won three gold medals in the 800 m at both the European Outdoor and Indoor Championships. He twice competed at the Olympic Games, in 2012 and 2016, narrowly missing the final on both occasions.
Alysia Montaño is an American middle distance runner. She is a six-time USA Outdoor Track and Field Championships 800 metres champion. She gained significant publicity for the 2014 race that she competed while 8 months pregnant.
Brenda Taylor is an American track and field athlete who specialises in the 400 meter hurdles. She reached the final of the event at the 2004 Summer Olympics. She also competed at the 2001 World Championships in Athletics and won a medal at the 2003 IAAF World Indoor Championships in the 4×400-meter relay.
Dmitriy Anatolyevich Bogdanov is a Russian middle-distance runner who specializes in the 800 metres. His personal best times are 1:44.33 minutes in the 800 metres and 46.50 seconds in the 400 metres.
Clayton Murphy is an American middle-distance runner. He won the bronze medal in the 800-meter run at the 2016 Olympic Games. He was the gold medalist in the 800-meter run at the 2015 Pan American Games. He ran collegiately for the University of Akron, before signing with Nike in June 2016 and joining the Nike Oregon Project.
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.
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.
Dominique Blake is a Jamaican track and field athlete. Blake won a gold medal at the 2010 Central American and Caribbean Games and was accidentally awarded a bronze medal at the 2012 Summer Olympics. She was banned for 4+1⁄2 years after testing positive for methylhexanamine and returned to athletic competition in 2017.
Athing Mu is an American middle-distance runner. She is the youngest woman in history to hold Olympic and world titles in an individual track and field event. At the age of 19, Mu won the gold medal in the 800 meters at the 2020 Tokyo Olympics, breaking a national record set by Ajeé Wilson in 2017, and a continental under-20 record. She took a second gold as part of the women's 4 × 400 m relay. She was the 800 m 2022 World champion, becoming the first American woman to win the world championship title over the distance.
Gregor Grahovac is a Slovenian athlete born in Ljubljana.
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