Aruba sent a delegation to compete at the 2004 Summer Olympics in Athens, Greece from 13 to 29 August 2004. The delegation's participation in the Athens Olympics marked Aruba's fifth appearance at the Summer Olympics since the Dutch colony's debut at the 1988 Summer Olympics in Seoul, South Korea. Four athletes competed across three sports. None of the track or swimming athletes advanced past the first round in their events, and as of Athens, no Arubans had medaled in any events. Roshendra Vrolijk bore Aruba's flag at the ceremonies.
Elaine Chan Yu-ning is a two-time Olympic swimmer from Hong Kong, specialized in freestyle events. At age sixteen, Chan first competed at the 2004 Summer Olympics in Athens, where she finished forty-seventh in the women's 50 m freestyle, with a time of 27.48 seconds. Following her remarkable performance at the Olympics, Chan granted a full scholarship to the Ohio State University in Columbus, Ohio, where she trained with the college swimming team for 18 months. In 2007, Chan returned to Hong Kong to pursue her education with a bachelor's degree in economics and finance at the University of Hong Kong, while she trained with the national team in preparation for the Olympics. She qualified for the 2008 Summer Olympics in Beijing, and competed for the second time in women's 50 m freestyle. She swam in the seventh heat of the competition, with a time of 26.54 seconds, bettering her personal best from the previous Olympics, but finishing only in forty-fourth place.
Martha Matsa is a Greek swimmer, who specialized in sprint freestyle events. She is a two-time Olympian, and a member of the swimming team for HAN Thessaloniki.
Ragnheiður Ragnarsdóttir, also known as Ragga Ragnars is an Icelandic actress and former swimmer, who specialised in sprint freestyle events. She is a multiple-time Icelandic record holder in both long and short course freestyle. After retiring from swimming, Ragnheiður studied acting and played the role of Gunnhild on the TV series Vikings from 2018 to 2020.
Sandra Kazíková is a Czech former swimmer, who specialized in sprint freestyle events. She posted a long-course national record time of 25.99 seconds, by winning the 50 m freestyle at the 2008 Czech Winter Championships in Pardubice. Kazikova is also a member of the swimming team for Slavia VŠ Plzeň, and is coached and trained by Ivana Felgrova.
Yelena Alexeyevna Skalinskaya is a Kazakh former swimmer, who specialized in sprint freestyle and breaststroke events. She is a five-time national champion and record holder in the same stroke. Skalinskaya is a member of the swimming team for Maryland Terrapins, along with her fellow country teammate Marina Mulyayeva.
Raichin Antonov is a Bulgarian former swimmer, who specialized in sprint freestyle events. He is a multiple-time Bulgarian record holder and champion in the 50 and 100 m freestyle. He is also a former member of the swimming team for the Missouri State Bears under head coach Jack Steck, and a business graduate at the Missouri State University in Springfield, Missouri.
Agnese Ozoliņa is a Latvian former swimmer, who specialized in sprint freestyle events. She is a three-time Olympian, a multiple-time Latvian and Baltic record holder, and a seven-time All-North Coast Atlantic Conference swimmer. She is also a varsity swimmer for the Kenyon Ladies, and an economics graduate at Kenyon College in Gambier, Ohio.
Maria Tregubova is a Moldovan former swimmer, who specialized in sprint freestyle events. She is a two-time Olympian and a member of the swimming team for Olimpia Chişinău.
Melanie Slowing de Montenegro is a Guatemalan former swimmer, who specialized in sprint freestyle events. Slowing qualified for the women's 50 m freestyle, as a 31-year-old, at the 2004 Summer Olympics in Athens, by breaking a Guatemalan record and posting a FINA B-cut of 26.89 from the Central American and Caribbean Championships in Mexico City. She topped the fourth heat by less than 0.04 of a second ahead of Moldova's Maria Tregubova in 27.44. Slowing failed to advance into the semifinals, as she placed forty-sixth overall out of 75 swimmers on the last day of preliminaries.
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.
Menaka Srimani de Silva is a Sri Lankan swimmer, who specialized in sprint freestyle events. She held a Sri Lankan record from the national championships in 2003 (28.28), until it was eventually broken by 13-year-old Kimiko Raheen nine years later (2012).
Sade Daal is a Surinamese swimmer, who specialized in sprint freestyle events. Daal qualified for the women's 50 m freestyle, as a 15-year-old, at the 2004 Summer Olympics in Athens, by receiving a Universality place from FINA, in an entry time of 29.14. She challenged seven other swimmers in heat four, including 31-year-old Melanie Slowing of Guatemala. She rounded out the field to last place in 29.27, just 0.13 of a second off her personal best. Daal failed to advance into the semifinals, as she placed fifty-fourth overall out of 75 swimmers on the last day of preliminaries.
Ermelinda Zamba is a Mozambican former swimmer, who specialized in sprint freestyle events. Zamba qualified for the women's 50 m freestyle at the 2004 Summer Olympics in Athens, by receiving a Universality place from FINA, in an entry time of 30.33. She cleared a 30-second barrier, and posted a lifetime best of 29.34 to lead the third heat, edging out Madagascar's Aina Andriamanjatoarimanana in a close race by one hundredth of a second (0.01). Zamba failed to advance into the semifinals, as she placed fifty-fifth overall out of 75 swimmers on the last day of preliminaries.
Eva Donde is a Kenyan swimmer, who specialized in sprint freestyle events. She held Kenyan records in long and short course 50 m freestyle, until they were both broken by Achieng Ajulu-Bushell in 2009. Donde is also a member of Otter Club, and is trained by her longtime coach Whitney Pragassa.
Tracy Ann Route is a Micronesian former swimmer, who specialized in sprint freestyle and butterfly events. She is a two-time Olympian, and holds numerous Pacific age group records in the freestyle and butterfly. She was the first woman to represent the Federated States of Micronesia at the Olympics.
Christal Ariana Clashing O'Reilly is an Antiguan swimmer, who specialized in sprint freestyle events. She also completed a Trans-Atlantic crossing as part of an all-woman team. As a one-time Olympian (2004), she is coached and trained by her mother Edith O'Reilly Clashing, who founded the Wadadli Aquatic Racers (WAR), an elite swim club in Antigua. Her sister Karin O'Reilly Clashing competed in the 50-metre freestyle at the 2012 Summer Olympics in London.
Han Choi is a Malawian swimmer, who specialized in sprint freestyle events. Choi became one of the first Malawian swimmers to compete at the 2004 Summer Olympics in Athens. She qualified for the women's 50 m freestyle, by receiving a Universality place from FINA in an entry time of 32.33. She challenged six other swimmers in heat two, including 14-year-olds Sameera Al-Bitar of Bahrain and Christal Clashing of Antigua and Barbuda. She posted a lifetime best of 31.62 to earn a fourth spot by 0.62 of a second behind joint winners Al-Bitar and Ghazal El Jobeili of Lebanon. Choi failed to advance into the semifinals, as she placed sixty-ninth overall on the last day of preliminaries.
Evelyn Ikelau Otto is a Palauan former swimmer. She swam for Palau at the 2004 Summer Olympics and at the 2003 World Championships.
Amira Edrahi is a Libyan swimmer, who specialized in sprint freestyle events.
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