The 400 metres hurdles is a track and field hurdling event. The event has been on the Olympic athletics programme since 1900 for men and since 1984 for women.
The 110 metres hurdles, or 110-metre hurdles, is a hurdling track and field event for men. It is included in the athletics programme at the Summer Olympic Games. The female counterpart is the 100 metres hurdles. As part of a racing event, ten hurdles of 42 inches (106.7 cm) in height are evenly spaced along a straight course of 110 metres. They are positioned so that they will fall over if bumped into by the runner. Fallen hurdles do not carry a fixed time penalty for the runners, but they have a significant pull-over weight which slows down the run. Like the 100 metres sprint, the 110 metres hurdles begins in the starting blocks.
The 100 metres hurdles, or 100-meter hurdles, is a track and field event run mainly by women. For the race, ten hurdles of a height of 33 inches (83.8 cm) are placed along a straight course of 100 metres (109.36 yd). The first hurdle is placed after a run-up of 13 metres from the starting line. The next 9 hurdles are set at a distance of 8.5 metres from each other, and the home stretch from the last hurdle to the finish line is 10.5 metres long. The hurdles are set up so that they will fall over if bumped into by the runner, but weighted so this is disadvantageous. Fallen hurdles do not count against runners provided that they do not run into them on purpose. Like the 100 metres sprint, the 100 m hurdles begins with athletes in starting blocks.
Zuzana Hejnová is a retired Czech athlete who specialised in the 400 metres hurdles. She won the silver medal in the event at the 2012 London Olympics. Hejnová is a two-time World Champion, having claimed titles at the 2013 and 2015 World Championships in Athletics. She won bronze at the 2012 European Championships and silver for the 400 metres at the 2017 European Indoor Championships.
Maoulida Darouèche is a Comoran hurdler who specialises in the 400 metres hurdles and who has also competed in the javelin throw. Darouèche competed in the 2012 Summer Olympics and the 2016 Summer Olympics. At both Olympics he competed in the 400 metres hurdles. He has also competed in two World Championships, an African athletics championships and a Jeux de la Francophonie.
Karsten Warholm is a Norwegian sprinter who competes in the 400 metres and 400 m hurdles. He is the 2020 Tokyo Olympic champion, a three-time world champion and the world record holder in the latter event.
Jaheel Hyde is a Jamaican track and field athlete. He was the 2014 world junior champion in the 400 metres hurdles and the 2013 world youth champion in the 110 metres hurdles.
Oluwakemi "Kemi" Adekoya is a Nigerian-born track and field athlete who competes for Bahrain. She specialises in the 400 metres hurdles and has a personal best of 53.39 seconds – a Bahraini and Asian record. In January 2019, it was reported that Adekoya tested positive for an illegal steroid stanozolol in an out-of-competition test in November 2018 and was provisionally suspended. All of her results achieved after 24 August 2018 were also stripped.
The men's 110 metres hurdles event at the 2016 Summer Olympics took place between 15–16 August at the Olympic Stadium. Forty athletes from 27 nations competed. The event was won by Omar McLeod of Jamaica, the nation's first gold medal and second medal overall in the event. Orlando Ortega's silver was Spain's first medal in the men's high hurdles, while Dimitri Bascou's bronze was France's first medal in the event since 1976.
Kristi Castlin is an American track and field athlete who specializes in the 100 metres hurdles. She won a bronze medal at the 2016 Olympics. Her personal best for the event is 12.50 seconds, set on July 8, 2016, during the finals of the 2016 United States Olympic Trials, in which she qualified for the 2016 Summer Olympics by placing 2nd. She was the 2012 American champion in the indoor 60 metres hurdles and represented the United States at the 2012 IAAF World Indoor Championships. She shares the world record for the shuttle hurdle relay, with her time of 50.78 seconds set in 2013.
Javier Arturo Mc Farlane Olazábal is a Peruvian track and field athlete who competes mainly in the 110 metres hurdles and long jump. He holds the Peruvian National Record for 110 metres hurdles with 13.52 seconds.
Milan Trajković is a Serbian-born Cypriot athlete specialising in the sprint hurdles. He has won two gold medals at the Games of the Small States of Europe.
Nicholas Kiplagat Bett was a Kenyan track and field athlete who competed in the 400 metres hurdles. His personal best for the event is 47.79 seconds. He was a world champion in the event, having won in 2015, and a two-time bronze medallist at the African Championships in Athletics. He died in a road accident in Kenya at the age of 28.
Jaak-Heinrich Jagor is an Estonian hurdler. He competed in the 400 metres hurdles event at the 2015 World Championships in Beijing without qualifying for the final. His personal best in the 400 metres hurdles is 49.37 seconds set in Tallinn in 2015.
Sebastian William Gregory "Seb" Rodger is a British athlete specialising in the 400 metres hurdles. In 2013, he won a silver medal at the European U23 Championships and reached the semifinals of the World Championships. He also represented Great Britain at the 2016 Olympic Games in Rio de Janeiro, Brazil.
Dharun Ayyasamy is an Indian track athlete. He specialises in the 400 metres and the 400 metres hurdles events. He participated in the 4 × 400 metres relay event at the 2016 Summer Olympics.
Yeison Javier Rivas Rivas is a Colombian hurdler. He represented his country in the 110 metres hurdles at the 2016 Summer Olympics without advancing from the first round. In addition, he won multiple medals on regional level.
Ned Justeen Azemia is a Seychellois hurdler who specialises in the 400 metres hurdles. He is the current Seychellois record holder in the event. Azemia competed in the 2016 Summer Olympics in Rio de Janeiro in the 400 metres hurdles. He has also competed in two World Junior Championships, an African athletics championships and an African Youth Games. Azemia has also raced over the flat 400 metres distance.
Ronald Levy is a Jamaican male track and field athlete who competes in the 110 metres hurdles. He holds a personal best of 13.05 seconds for that event, set in 2017, as well as a 100 metres sprint best of 10.17 seconds. He was the gold medallist at the 2018 Commonwealth Games and represented his country at the World Championships in Athletics in 2017.
The men's 110 metres hurdles event at the 2020 Summer Olympics took place between 3 and 5 August 2021 at the Olympic Stadium. Approximately forty athletes were expected to compete; the exact number was dependent on how many nations used universality places to enter athletes in addition to the 40 qualifying through time or ranking. 40 athletes from 29 nations competed. Hansle Parchment of Jamaica won the gold medal, the nation's second consecutive victory in the event. His countryman Ronald Levy took bronze. American Grant Holloway earned silver, placing the United States back on the podium in the event after the nation missed the medals for the first time in Rio 2016.
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