Nataliya Khudyakova is a Ukrainian swimmer, who specialized in freestyle events.
Susana Aylen Clement Quezada is a Cuban track and field athlete, who specialized in the 400 metres. She won gold medals for the national relay team at the 2009 Central American and Caribbean Championships in Havana, and also, at the 2011 Pan American Games in Guadalajara, Mexico.
Carline Muir is a Canadian sprinter, who specialized in the 400 metres. She won the bronze medal for the 400 metres, and ultimately, led her national team to claim the sprint relay title at the 2009 Summer Universiade in Belgrade, Serbia. She is also a three-time junior national champion, a two-time silver medalist at the Canadian Track and Field Championships.
Adrienne Power is a Canadian sprinter, who specialized in the 200 metres. She won two bronze medals for both the 200 metres and 4×400-metre relay at the 2010 Commonwealth Games in Delhi, India.
Konstadinos Anastasiou is a Greek sprinter, who specialized in the 400 metres. Anastasiou competed for the men's 4 × 400 m relay at the 2008 Summer Olympics in Beijing, along with his teammates Stylianos Dimotsios, Dimitrios Gravalos, and Pantelis Melachroinoudis. He ran on the anchor leg of the second heat, with an individual-split time of 46.63 seconds. Anastasiou and his team finished the relay in seventh place for a seasonal best time of 3:04.30, failing to advance into the final.
Dimitrios Gravalos is a Greek sprinter, who specialized in the 400 metres. He won the gold medal for the 400 metres at the 2003 European Junior Championships in Tampere, Finland, with a time of 46.54 seconds.
Pantelis Melachroinoudis is a Greek sprinter, who specialized in the 400 metres. Melachroinoudis competed for the men's 4 × 400 m relay at the 2008 Summer Olympics in Beijing, along with his teammates Stylianos Dimotsios, Konstadinos Anastasiou, and Dimitrios Gravalos. He ran on the third leg of the second heat, with an individual-split time of 45.15 seconds. Melachroinoudis and his team finished the relay in seventh place for a seasonal best time of 3:04.30, failing to advance into the final.
Dimitra Dova is a Greek sprinter, who specialized in the 400 metres. She won the gold medal for her category at the 2005 Mediterranean Games in Almería, Spain, with a time of 52.67 seconds, defeating her compatriot Phara Anacharsis by three hundredths of a second (0.03).
Mitsuhiro Abiko is a Japanese sprinter, who specialized in the 400 metres. Abiko competed in the men's 4 × 400 m relay at the 2008 Summer Olympics in Beijing, along with his teammates Kenji Narisako, Dai Tamesue, and Yoshihiro Horigome. He ran on the starting leg of the second heat, with an individual-split time of 46.70 seconds. Abiko and his team finished the relay in sixth place for a seasonal best time of 3:04.18, failing to advance into the final.
Sayaka Aoki is a Japanese track and field sprinter and hurdler, who specializes in the 400 metres sprint and 400 metres hurdles. She competed for her country as part of the Japanese women's 4 × 400 metres relay team at the Summer Olympics in 2008 and the World Championships in Athletics three times. She has been a four-time medallist in the relay at the Asian Athletics Championships, including a gold medal in 2011. She won her first major international medal in the hurdles – a bronze – at the 2017 Asian Athletics Championships.
Mayu Kida is a retired Japanese sprinter, who specialized in the 400 metres. Kida competed for the women's 4 × 400 m relay at the 2008 Summer Olympics in Beijing, along with her teammates Sayaka Aoki, Satomi Kubokura, and Asami Tanno. She ran on the third leg of the first heat, with an individual-split time of 52.72 seconds. Kida and her team finished the relay in last place for a seasonal best time of 3:30.52, failing to advance into the final.
Emmily da Silva Pinheiro is a Brazilian sprinter, who specialized in the 400 metres.
Josiane da Silva Tito is a Brazilian sprinter and middle-distance runner.
Maria Laura Almirão is a Brazilian sprinter, who specialized in the 400 metres. She is a two-time Olympian and a five-time medalist for the 400 metres and sprint relay at the Ibero-American Championships.
Yoel Armando Tapia Gómez is a Dominican sprinter, who specialized in the 400 metres. He won two medals for the national relay team at the 2007 Pan American Games in Rio de Janeiro, Brazil, and also, at the 2011 Pan American Games in Guadalajara, Mexico.
Kia Davis is a Liberian-American sprinter. She is a multiple-time national record holder in the sprint and hurdles, a three-time USA Track & Field national indoor finalist for the 60 m hurdles, and holds a dual citizenship for Liberia and the United States in order to compete internationally for her categories. She also won the silver medal, as a member of the U.S. team, in the women's 4 × 400 m relay at the 2006 IAAF World Indoor Championships in Moscow, Russia.
Jolanta Kajtoch is a Polish sprinter, who specialized in the 400 metres. Wojcik competed for the women's 4 × 400 m relay at the 2008 Summer Olympics in Beijing, along with her teammates Grażyna Prokopek, Anna Jesień, and Monika Bejnar. She ran on the second leg of the first heat, with an individual-split time of 51.72 seconds. Wojcik and her team finished the relay in sixth place for a total time of 3:28.23, failing to advance into the final.
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.
Pedro Juan Mejía Eusebio is a Dominican sprinter, who specialized in the 400 metres. He won two bronze medals, as a member of the Dominican Republic national team, in the men's 4 × 400 m relay at the 2007 Pan American Games in Rio de Janeiro, Brazil, and at the 2008 IAAF World Indoor Championships in Valencia, Spain.
Jovon Toppin is a Trinidadian sprinter, who specialized in the 400 metres. Toppin competed for the men's 4 × 400 m relay at the 2008 Summer Olympics in Beijing, along with his teammates Ato Modibo, Cowin Mills, and Stann Waithe. He ran on the second leg of the second heat, with an individual-split time of 45.92 seconds. Toppin and his team finished the relay in fifth place, for a seasonal best time of 3:04.12, failing to advance into the final.
Nigeria 
