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.
The 100 metres, or 100-meter dash, is a sprint race in track and field competitions. The shortest common outdoor running distance, the 100-meter (109.36 yd) dash is one of the most popular and prestigious events in the sport of athletics. It has been contested at the Summer Olympics since 1896 for men and since 1928 for women. The inaugural World Championships were in 1983.
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.
Tyler Christopher is a former Canadian sprinter who specialized in 400 meters. He is the Canadian record holder for the distance in outdoor competition.
Dame Valerie Kasanita Adams is a retired New Zealand shot putter. She is a four-time World champion, four-time World Indoor champion, two-time Olympic, three-time Commonwealth Games champion and twice IAAF Continental Cup winner. She has a personal best throw of 21.24 metres (69.7 ft) outdoors and 20.98 metres (68.8 ft) indoors. These marks are Oceanian, Commonwealth and New Zealand national records. She also holds the Oceanian junior record (18.93 m) and the Oceanian youth record (17.54 m), as well as the World Championships record, World Indoor Championships record and Commonwealth Games record.
Usain St. Leo Bolt is a retired Jamaican sprinter, widely considered to be the greatest sprinter of all time. He is the world record holder in the 100 metres, 200 metres, and 4 × 100 metres relay.
Moses Ndiema Kipsiro is a Ugandan long-distance runner who specialises in the 5000 metres. He was the bronze medallist in the event at the 2007 World Championships in Athletics. He represented Uganda at the 2008 Beijing Olympics, coming fourth over 5000 m.
The World Athletics Road Running Championships is a biennial international road running competition organised by World Athletics. The competition was launched as the IAAF World Half Marathon Championships in 1992 and held annually until 2010. It was renamed the IAAF World Road Running Championships in 2006 and reduced in distance to a 20K run, but reverted to the half marathon distance the following year and to the original competition name the year after that. The competition was renamed to its current title in 2020 after the governing body rebranded itself moving away from the long-standing International Association of Athletics Federations (IAAF) moniker and expanded to include additional races.
Dawn Harper-Nelson is an American track and field athlete who specializes in the 100-meter hurdles. She was the gold medalist in the event at the 2008 Beijing Olympic Games and the silver medalist in the 2012 London Olympic Games and the 2017 World Championships. Harper is the first American 100-meter hurdler to ever win gold at an Olympics and medal in the following Olympics. She is trained by Bob Kersee, husband of Jackie Joyner-Kersee, six time Olympic medalist also from her hometown of East St. Louis, Illinois. She is a member of the 2022 class of the UCLA Athletics Hall of Fame.
The women's 100 metres hurdles at the 2009 World Championships in Athletics was held at the Olympic Stadium 18 and 19 August.
Jackson Gill is a New Zealand track and field athlete who competes in the shot put. Gill throws with his right hand, using the spin technique. In 2010, he won gold in the shot put at the World Junior Championships at the age of 15 years, 213 days, which made him the youngest ever male gold medalist at the World Junior Championships. In 2012, he defended his title at the 2012 World Junior Championships.
Sheila Reid is a Canadian track and field Olympian who competes in cross country, middle and long-distance running events. She competed collegiately at Villanova University. Reid won the 2010 and 2011 NCAA Women's Cross Country Championship, and in June 2011 became the first woman to win the 5000 m and the 1500 m at the NCAA Women's Outdoor Track and Field Championship. She won the Honda Sports Award as the nation's top female cross country runner in 2011, repeated as the best female cross country runner in 2012, and also won the Honda Sports Award for Track and field in 2012.
The Central American and Caribbean Athletic Confederation (CACAC) is a confederation governing body of athletics for national governing bodies and multi-national federations within Central America and the Caribbean. Membership of the Confederation is open to all national governing bodies for the sport of athletics in any country or territory in the region which is affiliated to World Athletics. Other countries may be granted observer status and may, with permission of the Congress, be allowed to compete in open championships. They will, however, not be entitled to vote at the Congress.
The 2017 IAAF World Championships, the sixteenth edition of the IAAF World Championships, were held from 4 to 13 August at London Stadium in London, United Kingdom. London was officially awarded the championships on 11 November 2011.
Reid Coolsaet is a Canadian long-distance runner who competes in the marathon.
The NACAC U23 Championships in Athletics is an under-23 athletics competition held between the member associations of the North American, Central American and Caribbean Athletic Association (NACAC). Rules and regulations were approved at an extraordinary meeting of the members attending the XVIII Central American and Caribbean Games in Maracaibo, Venezuela held on August 18, 1998. First, the competition was open for athletes aged under-25. The Congress held on the island of Grenada on July 3, 2003, resulted in the reduction of the age limit for its bi-annual championships to athletes under-23 years of age in the year of competition.
Mohammed Ahmed is a Canadian long-distance runner. A three-time Olympian, he is his country's most successful athlete in long distance racing, being the first to medal in the 5000 metres at both the World Championships and the Olympic Games.
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