Until 2003 Tsoumeleka was a largely unknown athlete, and she only finished seventh at the World Championships that year. To everybody's great surprise, she won the Olympic gold medal race held in her own country ahead of Russia's Olimpiada Ivanova (silver) and Australia's Jane Saville (bronze).
In the 2008 Beijing Olympic Games, she finished 9th in 20 km walk. After the end of the Games, a urine sample she had given on August 6 tested positive for erythropoietin, when subjected to a new test for CERA. Tsoumeleka expressed doubts about the validity of the procedure, and then announced her immediate retirement from the sport. On April 29, 2009 it was announced that Tsoumeleka had tested positive for CERA in a test on a blood sample provided during the 2008 Olympics. Her "B" sample also tested positive for CERA. On November 18, 2009 the International Olympic Committee decided to disqualify Tsoumeleka from the Women's 20 km Walk event of the 2008 Olympic Games where she placed 9th.
|2002||European Championships||Munich, Germany||9th||20 km|
|2003||European U23 Championships||Bydgoszcz, Poland||1st||20 km|
|World Championships||Paris, France||7th||20 km|
|2004||Olympic Games||Athens, Greece||1st||20 km|
|2005||World Championships||Helsinki, Finland||DSQ||20 km|
|2008||Olympic Games||Beijing, PR China||DSQ||20 km|
|World Race Walking Cup||Cheboksary, Russia||14th||20 km|