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 4 × 100 metres relay or sprint relay is an athletics track event run in lanes over one lap of the track with four runners completing 100 metres each. The first runners must begin in the same stagger as for the individual 400 m race. Each runner carries a relay baton. Before 2018, the baton had to be passed within a 20 m changeover box, preceded by a 10-metre acceleration zone. With a rule change effective November 1, 2017, that zone was modified to include the acceleration zone as part of the passing zone, making the entire zone 30 metres in length. The outgoing runner cannot touch the baton until it has entered the zone, and the incoming runner cannot touch it after it has left the zone. The zone is usually marked in yellow, frequently using lines, triangles or chevrons. While the rule book specifies the exact positioning of the marks, the colours and style are only "recommended". While most legacy tracks will still have the older markings, the rule change still uses existing marks. Not all governing body jurisdictions have adopted the rule change.
The 4 × 400 metres relay or long relay is an athletics track event in which teams consist of four runners who each complete 400 metres or one lap. It is traditionally the final event of a track meet. At top class events, the first leg and the first bend of the second leg are run in lanes. Start lines are thus staggered over a greater distance than in an individual 400 metres race; the runners then typically move to the inside of the track. The slightly longer 4 × 440 yards relay, on an Imperial distance, was a formerly run British Commonwealth and American event, until metrication was completed in the 1970s.
Martyn Joseph Rooney is an English sprinter who specialises in the 400 metres event. He reached the 400 m final at the 2008 Summer Olympics and won bronze in the 4×400 metres relay. A mainstay on the anchor leg of the Great Britain and England 4 x 400 metre relay teams, at the 2009 World Championships in Athletics he won a silver medal with the Great Britain relay team, and bronze in the 2015 and 2017 World Championships.
Oscar Leonard Carl Pistorius is a South African former professional sprinter and convicted murderer. Both of his feet were amputated when he was 11 months old owing to a congenital defect; he was born missing the outside of both feet and both fibulae. Pistorius ran in both nondisabled sprint events and in sprint events for below-knee amputees. He was the 10th athlete to compete at both the Paralympic Games and Olympic Games.
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.
Ofentse Mogawane is a former South African sprinter who specialized in the 400 meters.
David Lekuta Rudisha, MBS is a Kenyan middle-distance runner who specialized in the 800 metres. He is a two-time back-to-back Olympic champion from the 2012 London and 2016 Rio Olympics, a two-time World champion from the 2011 and 2015 World Championships in Athletics, and world record holder at the event with a time of 1:40.91 set at the 2012 London Games on 9 August 2012. Rudisha is the first and only person to ever run 800 metres under 1:41, and he holds the three fastest, six of the eight fastest, and half of the twenty fastest times ever run in this event.
Michael Mathieu is a retired Bahamian sprinter from Freeport, Grand Bahama who specialized in the 200 metres and 400 metres. He was part of the Bahamian silver medal-winning team in the men's 4×400 metres relay at the 2008 Beijing Olympics, running second leg and recording a 44.0 split, and the gold medal-winning team at the 2012 Summer Olympics. He was also a part of second place relay team at the 2007 World Championships. He won the bronze medal in the 4x400 metres relay in the 2016 Summer Olympics.
David Kitur is a retired Kenyan runner, who specialised in 400 metres.
South Africa competed at the 2012 Summer Olympics in London, United Kingdom, from 27 July to 12 August 2012. This was the nation's eighteenth participation overall and sixth consecutive appearance at the Summer Olympics in the post-apartheid era. The South African Sports Confederation and Olympic Committee (SASCOC) sent a total of 125 athletes to the Games, 67 men and 58 women, to compete in 17 sports. Field hockey and women's football were the only team-based sports in which South Africa were representation at these Olympic Games. There was only a single competitor in archery, BMX cycling, judo, shooting and weightlifting.
The athletics competitions at the 2012 Olympic Games in London were held during the last 10 days of the Games, on 3–12 August. Track and field events took place at the Olympic Stadium in east London. The road events, however, started and finished on The Mall in central London.
The men's 4 × 400 metres relay competition at the 2012 Summer Olympics in London, United Kingdom. The event was held at the Olympic Stadium on 9–10 August. It was won by the Bahamas.
The Men's 4 × 400 metres relay event at the 2011 World Championships in Athletics was held at the Daegu Stadium on 1 and 2 September. Thursday and Friday. This is a change in schedule from previous years when all the relays were at the end of the program. This might necessitate a change in strategy to allow for team members involved in other events.
Athletics at the 2016 Summer Olympics were held during the last 10 days of the games, from 12 to 21 August 2016, at the Olympic Stadium. The sport of athletics at the 2016 Summer Olympics was made into three distinct sets of events: track and field events, road running events, and racewalking events.
Shane Victor is a South African sprinter who specializes in the 400 metres. He won a silver medal in the 4 × 400 m relay at the 2011 World Championships in Athletics in Daegu.
Shaun de Jager is a South African sprinter. He competed in the 4 × 400 m relay event at the 2012 Summer Olympics.
Blake Leeper is a United States Paralympic athlete, eight-time Paralympic Track and Field international medalist, world record holder and three-time American record holder.
Pieter Smith is a South African sprinter, who specialized in the 400 metres. He set his personal best time of 45.63 seconds by winning the 400 metres event at the 2009 South African Championships in Stellenbosch.
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.
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