Career
Ryu qualified for two swimming events at the 2004 Summer Olympics in Athens, by breaking a South Korean record and clearing a FINA A-cut of 55.46 (100 m freestyle) from the Dong-A Swimming Tournament in Seoul. On the first day of the Games, Ryu teamed up with Sun So-Eun, Shim Minister-Ji, and Kim Hyun-Joo in the women"s 4×100 m freestyle relay. Swimming the second leg, Ryu recorded a fastest split time of 55.24 seconds, and the South Korean team went on to finish the first heat in fifth place, for a total time of 3:44.84.
In the women"s 100 m freestyle, Ryu missed out the semifinals by a hundredth of a second (001) in 55.02, but offered a second chance, after Germany"s Franziska van Almsick scratched the event to focus on German relay duty in the 800 m freestyle relay.
Ryu failed to qualify for the final, as she finished her semifinal run with a second slowest time of 55.85 seconds. In her final event, 50 m freestyle, Ryu raced to fifth place in heat seven by 0.06 of a second behind Venezuela"s Arlene Semeco in 26.26.
Unlike her previous individual event, Ryu failed to advance into the semifinals, as she placed twenty-sixth out of 75 swimmers in the preliminary heats. She also tied her position with Puerto Rico"s Vanessa García.