Andrzej Stanisław Badeński was a Polish sprinter who specialized in the 400 metres. He won a bronze medal in that event at the 1964 Summer Olympics, and won the gold medal in that event at the European Indoor Championships in 1968 and in 1971.
Louis Jacobus van Zyl, better known as L. J. van Zyl, is a South African athlete competing in the 400 metre hurdles. He is the South African record holder in the event with a personal best of 47.66 seconds, which he achieved twice, three months apart. His time ranks him in the all-time top 25. He is a three-time African Champion in the event and competed for his country at the 2008, 2012 and 2016 Summer Olympics.
Rabah Mahhamed Yousif Bkheit is a Sudanese-born British track and field athlete, who initially competed for Sudan before obtaining British citizenship.
David Kitur is a retired Kenyan runner, who specialised in 400 metres.
Deon Kristofer Lendore was a Trinidad and Tobago sprinter who specialised in the 400 metres. He won a bronze medal in the 4 × 400 metres relay event at the 2012 Summer Olympics, and won medals at the Pan American Junior Athletics Championships, World Athletics Championships and World Athletics Indoor Championships. Lendore died in a car collision in Texas, United States, on 10 January 2022.
Jereem Richards is a Trinidadian track and field sprinter who specializes in the 200 metres and 400 metres events. He won the bronze medal in the 200 m at the 2017 World Championships in Athletics and gold for the 400 m at the 2022 World Indoor Championships. Richards took 200m titles at both the 2018 and 2022 Commonwealth Games. He was part of the Trinidad and Tobago team that won the bronze medal in the men's 4 × 400 m relay at the 2012 World Indoor Championships and a gold medal at the 2017 World Championships in Athletics.
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.
Karsten Warholm is a Norwegian sprinter who competes in the 400 metres and 400 m hurdles. He is the 2020 Tokyo Olympic champion, silver medalist at the 2024 Paris Olympics, three-time world champion and world record holder in the latter event.
Matthew Hudson-Smith is a British track and field sprinter who specialises in the 400 metres and is the 5th fastest athlete of all-time over the distance. In September 2024 he was ranked as the number one 400m runner in the world and has won six British titles, five Diamond League events, two individual European titles, an individual Olympic silver medal, World Championships silver and bronze individual medals and an individual Commonwealth silver medal. He has also won a number of relay titles including an Olympic bronze medal, World Championships bronze medal, two European gold medals, one European silver medal, one European bronze medal and a Commonwealth Games gold medal. Hudson-Smith also holds the European and British 4x400m records (2:55.83) along with the GB Team who ran in the final of the men's 4x400m event in the Paris 2024 Olympics.
Janieve Russell is a Jamaican track and field athlete who competes mainly in the 400 metres hurdles and the 400 metres sprint. She won an Olympic bronze medal in the 4 × 400 m relay in Tokyo 2021, where she also finished fourth in the 400m hurdles final in a personal best of 53.08 secs. She is a four-time Commonwealth Games gold medallist, winning the 400m hurdles title in 2018 and 2022, and the 4 × 400 m relay in 2014 and 2018. She has also won two relay silvers at the World Championships and a relay gold at the World Indoor Championships.
Vernon Larnard Norwood is an American track and field athlete who specializes in the 400 meters.
Luiz Altamir Lopes Melo is a Brazilian swimmer.
Abderrahman Almoubarrake Samba Alsaleck is a Qatari male track and field athlete who specialises in the 400 metres hurdles. He was born and raised in Saudi Arabia but chose to represent Mauritania – his father's homeland – before eventually switching allegiance to Qatar and moving to Doha in 2015. He became eligible to compete for his adopted country in May 2016. He was the second person to run the 400m hurdle event in less than 47 seconds.
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.
Alexander Doom is a Belgian sprinter specializing in the 400 metres. In 2024, he became the first male athlete to win the individual 400 metres and 4×400 metres relay at the same World Athletics Indoor Championships He has won several medals in international competitions with the Belgian 4 × 400 metres relay team and holds a personal best of 44.15 over the 400 metres.
Jonathan Jones is a sprinter from Barbados.
Sean Bailey is a Jamaican athlete.
Alexander (Alex) Beck is an Australian Olympic athlete. He is a three time defending National champion.
Imaobong Nse Uko is a Nigerian athlete. She competed in the mixed 4 × 400 metres relay event at the 2020 Summer Olympics. The 17-year-old won the 400 metres at the 2021 World Under 20 Championships.
Zakithi Nene is a South African sprinter, who specializes in the 400 metres.
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