Bahrain sent a delegation to compete at the 2000 Summer Olympics in Sydney, Australia, which were held from 15 September to 1 October 2000. This was the fifth consecutive Summer Olympics the Kingdom took part in. The delegation consisted of four athletes: sprinter Mariam Mohamed Hadi Al Hilli, middle-distance runner Mohamed Saleh Naji Haidara and short-distance swimmers Dawood Yosuf Mohamed Jassim and Fatema Hameed Gerashi. Al Hilli and Gerashi's inclusion in the Bahraini delegation was the first time in history a Gulf Arab nation had sent female athletes to the Olympic Games. All four did not progress beyond the initial heats of their respective competitions. Bahrain's best performance came from Haidara and Jassim who placed seventh in the heats of the men's 800 metres and the men's 100 metres freestyle. Gerashi was disqualified for a false start in the women's 50 metres freestyle and Al Hilli came eighth in her heat in the women's 100 metres.
Yuliya Andreyevna Yefimova is a Russian competitive swimmer. She is the Russian record holder in the 200 metre individual medley, 50 metre breaststroke, 100 metre breaststroke, and 200 metre breaststroke. After making her Olympic debut in 2008, she went on to win the bronze medal in the 200 metre breaststroke in 2012, and silver medals in the 100 metre and 200 metre breaststroke in 2016. She is a six-time World Champion, winning the 50 metre breaststroke in 2009 and 2013, the 100 metre breaststroke in 2015, and the 200 metre breaststroke in 2013, 2017, and 2019. In 2019, she became the first woman to win the 200 metre breaststroke at a FINA World Aquatics Championships three times. She is a former world record holder in the long course 50 metre breaststroke. She has won 109 medals, including 48 gold medals, at Swimming World Cups.
Alia Shanee Atkinson, OD is a Jamaican five-time Olympian and a former competitive swimmer whose international competition career spanned 19 years, 2003 to 2021 inclusive, at the senior level. At short course World Swimming Championships, she is a ten-time medalist in individual events, including four gold medals, four silver medals, and two bronze medals. She won a total of 124 medals, of which 74 were gold medals, at Swimming World Cup circuits over the course of her career. She won 14 total medals in individual events, 11 gold, 1 silver, and 2 bronze, from her first three Central American and Caribbean Games, in 2006, 2010, and 2018.
Giedrius Titenis is a Lithuanian swimmer, who specialized in breaststroke events. He is a four-time Olympian, a multiple-time Lithuanian record holder in the men's breaststroke, and a double swimming champion in the same discipline at the 2011 Summer Universiade in Shenzhen, China. Titenis is also a member of Anykščiai Swimming Club, and is coached and trained by Žilvinas Ovsiukas.
Kenneth King-him To was a Hong Kong Australian swimmer who practised individual medley, freestyle, butterfly and breaststroke. He won 6 medals at the 2010 Summer Youth Olympics, was the male overall winner of the 2012 FINA Swimming World Cup and was a World Championships silver medallist. He was the holder of 16 Hong Kong national swimming records.
Rūta Meilutytė is a Lithuanian swimmer. An Olympic gold medalist, she is a world record holder in the short course 50 metre breaststroke and 100 metre breaststroke. She is a former world record holder in the long course 50 metre breaststroke and 100 metre breaststroke.
Roshendra Julienne Mercedes Vrolijk is an Aruban former swimmer, who specialized in sprint freestyle events. She is one of Aruba's first Olympic swimmers, alongside Davy Bisslik, and also a two-time Olympian.
Karar Samedul Islam is a Bangladeshi former swimmer, who specialized in breaststroke events. Islam competed only in the men's 100 m breaststroke at the 2000 Summer Olympics in Sydney. He received a Universality place from FINA, in an entry time of 1:09.51. He challenged six other swimmers in heat two, including two-time Olympians Juan José Madrigal of Costa Rica and Jean Luc Razakarivony of Madagascar. With one swimmer casting out of the race for a no false-start rule, Islam rounded out the field to last place in 1:14.93, almost ten seconds farther behind leader Madrigal. Islam failed to advance into the semifinals, as he placed sixty-fourth overall on the first day of prelims.
Antonio Manuel Leon Candia is a Paraguayan former swimmer, who specialized in breaststroke events. During his sporting career, he represented Paraguay, as an eighteen-year-old, at the 2000 Summer Olympics, and in all four editions of the FINA World Championships since 2001. Leon also trained for Deportivo de Puerto Sajonia, under his longtime coach and mentor Roberto Colmán.
Kieran Chan is a Papua New Guinean former swimmer, who specialized in breaststroke events. Chan competed for Papua New Guinea in the men's 100 m breaststroke at the 2000 Summer Olympics in Sydney. He received a Universality place from FINA, in an entry time of 1:14.40. He participated in heat one against two other swimmers Antonio Leon of Paraguay and Joe Atuhaire of Uganda. Diving in with a 0.95-second deficit, Chan enjoyed the race of his life to take only a second seed in a lifetime best of 1:13.34. Chan failed to advance into the semifinals, as he placed sixty-third overall on the first day of prelims.
Jenny Rose Guerrero is a Filipino former swimmer, who specialized in breaststroke events. She represented the Philippines, as the youngest ever athlete of the squad, at the 2000 Summer Olympics, in Sydney. She won two medals at the 2001 Southeast Asian Games in Kuala Lumpur, and later became a top 8 finalist at the 2002 Asian Games in Busan, South Korea before her official retirement in 2005.
Nicolas Fink is an American five-time world champion in breaststroke events. He is a world record holder in the short course 4×100 meter medley relay and 4×50 meter mixed medley relay. He is the Americas record holder in the short course 50 meter breaststroke, 100 meter breaststroke, and 200 meter breaststroke as well as the American record holder in the long course 50 meter breaststroke. In the 50 meter breaststroke, he won the World Short Course titles in 2021 and 2022 and World Long Course title in 2022. In the 100 meter breaststroke, he is the 2022 World Short Course gold medalist. In the 200 meter breaststroke, he is the 2021 World Short Course gold medalist.
Adam George Peaty is an English competitive swimmer who specialises in the breaststroke. He won the gold medal in the 100 metre breaststroke at the 2016 Summer Olympics, the first by a male British swimmer in 24 years, and retained the title at the 2020 Summer Olympics in 2021, the first British swimmer ever to retain an Olympic title. He is also an eight-time World Champion, a sixteen-time European Champion and a four-time Commonwealth Champion. According to FINA itself, Peaty is widely regarded as the dominant breaststroke swimmer of his era, and the most dominant sprint breaststroke swimmer of all time.
Anton Mikhailovich Chupkov is a Russian competitive swimmer. He is the European record holder in the long course 200 metre breaststroke and the Russian record holder in the long course 100 metre breaststroke. He formerly held the world record in the long course 200 metre breaststroke. At the 2015 European Games he won four gold medals in individual and relay events. He won the bronze medal in the 200 metre breaststroke at the 2016 Summer Olympics. He won the gold medal in the 200 metre breaststroke at the 2017 and 2019 World Aquatics Championships.
Michael Charles Andrew is an American competitive swimmer and an Olympic gold medalist. He was the 2016 world champion in the 100 meter individual medley. At his first Olympic Games, the 2020 Summer Olympics, he won a gold medal and set a world record as part of the 4x100 meter medley relay, placed fourth in the 100 meter breaststroke, fourth in the 50 meter freestyle, and fifth in the 200 meter individual medley. Andrew's swims in 2021 at the 2020 Olympics made him the first swimmer to represent the United States at an Olympic Games in an individual breaststroke event as well as another individual event other than an individual medley in the then-125-year-history of swimming at the Summer Olympics. He has won 78 medals at Swimming World Cup circuits.
Kaylene Corbett is a South African swimmer. She competed in the women's 100 metre breaststroke event at the 2017 World Aquatics Championships. At the 2022 Commonwealth Games, she won the bronze medal in the 200 metre breaststroke.
Ilya Syarheyevich Shymanovich is a Belarusian swimmer. He is the world record holder in the short course 100 metre breaststroke and a former world record holder in the short course 50 metre breaststroke. At the 2018 World Championships he won two silver medals, one each in the 100 metre breaststroke and the 50 metre breaststroke. He won two gold medals, one in the 50 metre breaststroke and one in the 200 metre breaststroke, and a silver medal, in the 100 metre breaststroke, at the 2021 European Short Course Championships. At the 2021 World Short Course Championships he won the gold medal in the 100 metre breaststroke.
Lydia Alice Jacoby is an American professional swimmer. She was the first Alaskan to qualify for an Olympic Games in swimming, competing at the 2020 Summer Olympics in Tokyo in 2021, where she won the gold medal in the 100-meter breaststroke with a time of 1:04.95, which was the fastest time ever achieved by a female American swimmer in the event in the 17–18 age group. Later in the year, she was the overall highest scoring female American competitor at the 2021 FINA Swimming World Cup. In 2022, she became the fastest female American swimmer in history in the 100-yard breaststroke for the 17–18 age group with a national age group record time of 57.54 seconds. In 2023, she further lowered the record to a time of 57.45 seconds, then 57.29 seconds, and set a national age group record of 2:04.32 for the girls 17–18 age group in the 200-yard breaststroke. She is the 2023 NCAA Division I champion in the women's 100-yard breaststroke.
Vladislav Gerasimenko is a Russian competitive swimmer. He is a world junior record holder in the long course 4×100 metre medley relay, swimming a 59.53 for the breaststroke portion of the relay. He is a four-time medalist at the 2018 Summer Youth Olympics and a five-time medalist at the World Junior Swimming Championships, spanning breaststroke and freestyle disciplines. He competed at the 2021 European Short Course Swimming Championships, placing sixteenth in the preliminaries of the 50 metre breaststroke.
Kirill Strelnikov is a Russian competitive swimmer. He won a gold medal in the 4×50 metre medley relay at the 2021 World Short Course Championships and the 4×100 metre medley relay at the 2013 World University Games, swimming the breaststroke leg of both relays in the final. At the 2021 European Short Course Championships he won a bronze medal in the 4×50 metre mixed medley relay, swimming the breaststroke leg of the relay in the preliminaries.
Uganda