Allyson Michelle Felix is a retired American track and field athlete who competed in the 100 meters, 200 meters and 400 meters. She specialized in the 200 meters from 2003 to 2013, then gradually shifted to the 400 meters later in her career. At 200 meters, Felix is the 2012 Olympic champion, a three-time world champion (2005–2009), a two-time Olympic silver medalist, and the 2011 world bronze medalist. At 400 meters, she is the 2015 world champion, 2011 world silver medalist, 2016 Olympic silver medalist, 2017 world bronze medalist, and 2020 Olympic bronze medalist. Across the short distances, Felix is a ten-time U.S. national champion.
Shaunae Miller-Uibo is a Bahamian track and field sprinter who competes in the 200 and 400 metres. She is a two-time Olympic champion after winning the women's 400 metres at the 2016 Rio Olympics and again at the 2020 Tokyo Olympics.
Phyllis Chanez Francis is an American track and field athlete. She won the gold medal at the 2017 World Championships in the 400 metres and 4 × 400 metres relay events.
The women's 400 metres event at the 2016 Summer Olympics took place between 13–15 August at the Olympic Stadium.
The Bahamas, officially the Commonwealth of The Bahamas, competed at the 2016 Summer Olympics in Rio de Janeiro, Brazil, from 5 to 21 August 2016. The nation's participation at these Games marked its seventeenth appearance as an independent nation.
The women's 400 metres at the 2015 World Championships in Athletics was held at the Beijing National Stadium on 24, 25 and 27 August. Christine Ohuruogu of Great Britain entered the competition as the defending champion.
Salwa Eid Naser is a Nigerian-born Bahraini sprinter who specialises in the 400 metres. She was the 2019 World champion with the third fastest time in history of 48.14 seconds, becoming the youngest-ever champion in the event and also the first woman representing an Asian nation to win that event at a World Championships. The mark places her only behind contested results of Marita Koch and Jarmila Kratochvílová. Over the distance, at only 19, Naser was the 2017 World silver medallist. She has also won, as a member of the Bahraini mixed-gender 4x400 m relay team, the 2019 World Championships bronze medal.
The men's 200 metres at the 2017 World Championships in Athletics was held at the London Olympic Stadium on 7, 9, and 10 August. The winning margin was 0.02 seconds.
The women's 200 metres at the 2017 World Championships in Athletics was held at the London Olympic Stadium on 8 and 10−11 August.
The women's 4 × 100 metres relay at the 2017 World Championships in Athletics was held at the London Olympic Stadium on 12 August.
The women's 4 × 400 metres relay at the 2017 World Championships in Athletics was held at the London Olympic Stadium on 12–13 August.
The women's 200 metres event at the 2020 Summer Olympics took place on 2 and 3 August 2021 at the Japan National Stadium. 41 athletes from 31 nations competed. In successfully defending her title, Elaine Thompson-Herah became the first woman in history to win both the 100 and 200 metres titles at successive games. Her winning time of 21.53 secs, moved her to second on the world all-time list behind Florence Griffith Joyner, and broke Merlene Ottey's 30-year-old Jamaican record. The winning margin was 0.28 seconds. Surprisingly, Thompson-Herah had the slowest reaction time in the final.
The women's 400 metres event at the 2020 Summer Olympics took place from 3 to 6 August 2021 at the Japan National Stadium. 45 athletes from 34 nations competed. Shaunae Miller-Uibo won the gold medal by 0.84 seconds in a personal best of 48.36 secs, a time which ranks her sixth on the world all-time list. In successfully defending her title, Miller-Uibo joined Marie-Jose Perec as the only women to win two Olympic 400 metres titles.
The women's 200 metres at the 2019 World Athletics Championships was held at the Khalifa International Stadium in Doha, Qatar, from 30 September to 2 October 2019.
The women's 400 metres at the 2019 World Athletics Championships was held at the Khalifa International Stadium in Doha, Qatar, from 30 September to 3 October 2019.
The women's 4 × 400 metres relay at the 2019 World Athletics Championships was held at the Khalifa International Stadium in Doha, Qatar, from 5 to 6 October 2019. In the final the Jamaican team were initially disqualified, but were reinstated as the bronze medallists upon appeal.
The women's 400 metres at the 2022 World Athletics Indoor Championships took place on 18 and 19 March 2022.
The women's 400 metres at the 2022 World Athletics Championships was held at the Hayward Field in Eugene, Oregon, U.S. from 17 to 22 July 2022.
The women's 400 metres at the 2022 European Athletics Championships took place in three rounds at the Olympiastadion in Munich, Germany, from 15 to 17 August 2022.
The women's 400 metres at the 2024 Summer Olympics was held in four rounds at the Stade de France in Paris, France, between 5 and 9 August 2024. This was the sixteenth time that the women's 400 metres was contested at the Summer Olympics. A total of 48 athletes were able to qualify for the event by entry standard or ranking.
