Lance Armstrong to admit doping in Oprah interview

After years of denial, cyclist Lance Armstrong plans to confess to doping during his long and successful career, which produced a record seven Tour de France titles.

Several sources say Armstrong will come clean in an interview with Oprah Winfrey, which will be taped Monday. The interview will air on Thursday.

Details of the interview have not been released, so it isn't exactly clear how much Armstrong will say about his role in what has been called the most comprehensive doping cover-up in sports history. According to a statement on her website, Winfrey's says it will be a "no-holds-barred interview."

So why now? Why admit to it after years of denial, libelous lawsuits and millions in donations to his Livestrong Foundation? Sources say Armstrong hopes to earn some sympathy for his foundation, which helps cancer victims battle their disease. He no longer sits on the board of the foundation. Armstrong, 41, also hopes to have a shot at returning to competition. The cancer survivor was a competitive triathlete after his cycling career ended, but received a lifelong ban from competing in any event sanctioned by the World Anti-Doping Agency after he was stripped of his titles.