Olympic cross-country mountain bike gold medallist Sabine Spitz says she was offered EPO and other doping products by a sports doctor in 2003.
She told the German magazine Sport-Bild she would "rather ride behind the others" than dope.
Spitz said when, shortly afterwards, she became world champion " that showed me it is possible to win clean".
She added: "I want to be able to look at myself in the mirror every morning."
Spitz, 36, clarified in a separate press release that it was not a doctor from the Bund Deutscher Radfahrer (BDR, German federation). She did not name the doctor.
As a deterrent to doping, she suggested life-long bans or prison. "For me, doping is cheating and criminal. If there is a threat of imprisonment, then maybe people will think twice before they take some illegal product."
She also said she did not think Lance Armstrong's return would be beneficial to cycling. Spitz said tests from the 1999 Tour de France linked him to EPO use, and added: "I absolutely do not understand why he is welcomed back with open arms."