In a release, the International Olympic Committee (IOC) explained how the swimmer admitted her guilt after buying a product online containing EPO, a blood-boosting drug particularly advantageous in endurance events. 

This followed re-analysis of urine samples in March this year of a test originally conducted in a pre-Games test in Kyiv on July 28, 2012, with the latter test at a laboratory in Cologne taking advantage of "improved analytical methods".

Beresnyeva's case was considered by an IOC disciplinary commission chaired by Switzerland's IOC member Denis Oswald.

The athlete, who won a 25 kilometres gold medal at the 2010 European Championships in Budapest, waived her right to attend a hearing, instead admitted to the violation following her "fatal mistake".

She admitted to ordering a medication called "Eprex", starting to take it in mid-June of 2012 and continuing to do so on a weekly basis until the beginning of the Games.

Although a blow, the result is also a triumph for the IOC's retesting programme, with samples being reviewed from as far back as the Athens 2004 Olympics, 

Samples were retested a year after the 2008 Beijing Games, with the five athletes caught including Bahrain's 1500m winner Rashid Ramzi. 

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