Konstantinos "Kostas" Kenteris, also spelled as Konstadinos "Costas" Kederis is a Greek former athlete. He won gold medals in the 200 metres at the 2000 Summer Olympics, the 2001 World Championships in Athletics and the 2002 European Championships in Athletics, making him the only European sprinter to win the gold medal in all three major competitions and the only European World Champion in the 200 metres races. Additionally, he has won two gold, three silver and two bronze medals in the European Cup, as well as three gold medals in the 200 metres at the Athens Grand Prix Tsiklitiria. He is also a 14-time golden medalist at the Greek Athletics Championships and a five-time golden medalist at the Greek Indoor Athletics Championships. He withdrew from the 2004 Summer Olympics, held in his home country, after a doping violation.
Kerron Stephon Clement is a Trinidadian-born American track and field athlete who competes in the 400-meter hurdles and 400-meter sprint. He held the indoor world record in the 400-meter sprint, having broken Michael Johnson's mark in 2005.
Sanjay Claude Ayre is a retired Jamaican sprinter who specialized in the 400 meters. Ayre won a silver medal at the 2000 Summer Olympic Games. Ayre is a 2004 IAAF World Indoor Championship Gold medalist and a three-time World Outdoor Championship medalist.
Bertland "Bert" Cameron is a retired Jamaican sprinter who mainly competed over 400 metres. He represented Jamaica at three consecutive editions of the Summer Olympics. Cameron won the 400 m title at the first World Championships in Athletics. He was also the 1982 Commonwealth Games champion in the event and won a number of gold medals at regional competitions. He helped the Jamaican runners to a silver medal in the 4×400 metres relay at the 1988 Seoul Olympics.
David Gillick is an Irish international track and field athlete. He began his education in Our Lady's Boys School and attended St Benildus College secondary school in Kilmacud. He studied at Dublin Institute of Technology before moving to Loughborough University in the United Kingdom to train as a full-time athlete with coach Nick Dakin. Gillick specialises in the 400 metres and he won the European Indoor Championship in 2005 and 2007, as well as the Irish National Outdoor Championship in 2006 and 2007. He set the Irish Indoor record of 45.52 seconds in the 2007 final. The time also beat the Irish outdoor record of 45.58 and was within the Olympic 'A' qualifying standard for the 2008 Games. On 4 July 2009 he ran 44.77 seconds in a race in Madrid to set a new national record. He is also the 2009 Irish national 200 m champion.
Richard Thomas Buck is a former British sprinter who specialised in the 400 metres event. He is from York, and trains in Loughborough. Buck's current club is City of York A.C.. Previously, he had an 18-month spell at Scarborough A.C. He has been trained by his grandfather, Geoff Barraclough, and is now coached by Nick Dakin.
Willie James Smith III was an American athlete who was the national champion 400 metres runner in 1979-80, and a gold medal winner at the 1984 Olympics in the 4 × 400 m relay.
Yousef Ahmed Masrahi is a Saudi Arabian track and field athlete, who specialises in the 400 metres sprint. His personal best time for the event is 43.93 seconds, set in 2015, and is the Asian record.
Christian Taylor is a retired American track and field athlete who competed in the triple jump and has a personal record of 18.21 m, which ranks 2nd on the all-time list.
Jacques Borlée is a former Belgian athlete, and the father and coach of athletes Olivia Borlée, Kevin, Jonathan and Dylan Borlée. He was voted European Athletics Coach of the Year in 2011.
Omar Cisneros Bonora is a Cuban track and field athlete who competes in the 400 metres hurdles. He is the Cuban national record holder for the event with his personal best of 47.99 seconds. He won gold medals in the hurdles and 4×400 metres relay at the Pan American Games in 2011.
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.
Mehdi Zamani is an Iranian track and field sprinter who specialises in the 400 metres, who was banned for two years for doping.
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.
Dylan Borlée is a Belgian sprinter who competes in the 400 metres. He is a member of the Borlée family.
Mohammad Hossein Abareghi is a male Iranian sprinter. He failed a doping test for the steroid stanozolol, and was banned from the sport for four years, beginning in August 2015.
Inaldo Justino de Sena is a Brazilian former male track and field sprinter who specialised in the 400 metres. He represented his country at the World Championships in Athletics in 1995 and took a bronze medal at the 1994 IAAF World Cup. He won two gold and four silver medals at the Ibero-American Championships in Athletics during his career.
Suziann Reid is an American-Jamaican former track and field sprinter who specialized in the 400-meter dash. She set a personal record of 50.74 seconds for the distance in 1999. She was a silver medalist with the American women's 4 × 400-meter relay team at the 1999 World Championships in Athletics. She was part of the World Championship team twice more, in 2001 and 2005, and helped the United States to silver at the 2002 IAAF World Cup and gold at the 2001 Goodwill Games.
Christopher O'Donnell is an Irish track and field athlete competing in sprinting events. He was part of the Irish Mixed 4x400m team who won a gold medal at the 2024 European Athletics Championships. He represented Ireland at the Tokyo 2020 Olympic Games in the Mixed 4 × 400 m relay, where he was part of the first ever Irish team to run in an Olympic final, and competed in the same event at the Paris 2024 Olympic Games. He was also part of the team who reached the final of the 2022 and 2023 World Championships. He is the current Irish U20 record holder in the 400m, his personal best of 45.26 seconds sits joint-2nd on the Irish all-time list and he is a 5-time National 400m champion.
Charlie Dobson is a British sprinter, specialising in the 400 metres and the 4 x 400 metres relay. An Olympic bronze medalist and European champion in the relay, Dobson made his senior indivudual breakthrough in 2024; he won a silver medal in the 400 metres at the 2024 European Athletics Championships, and won the 400 metres event at the 2024 British Athletics Championships. In September 2024 he won his first individual and global title, when he was the surprise winner in the 400 metres final of the 2024 Diamond League in Brussels.
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