AP Source: Lance Armstrong Tells Winfrey He Doped Lance Armstrong has finally come clean. After years of bitter and forceful denials, he offered a simple "I'm sorry" to friends and colleagues and then admitted he used performance-enhancing drugs during an extraordinary cycling career that included seven Tour de France victories. Armstrong confessed to doping during an interview with Oprah Winfrey taped Monday, just a couple of hours after an emotional apology to the staff at the Livestrong charity he founded and was later forced to surrender, a person familiar with the situation told The Associated Press. The person spoke on condition of anonymity because the interview is to be broadcast Thursday on Winfrey's network. The confession was a stunning reversal for the proud athlete and celebrity who sought lavish praise in the court of public opinion and used courtrooms to punish his critics. For more than a decade, Armstrong dared anybody who challenged his version of events to prove it. Finally, he told the tale himself after promising over the weekend to answer Winfrey's questions "directly, honestly and candidly." Winfrey was scheduled to appear on "CBS This Morning" on Tuesday morning to discuss the interview. She tweeted shortly after the interview: "Just wrapped with (at) lancearmstrong More than 2 1/2 hours. The cyclist was stripped of his Tour de France titles, lost most of his endorsements and was forced to leave Livestrong last year after the U.S. Anti-Doping Agency issued a damning, 1,000-page report that accused him of masterminding a long-running doping scheme. Armstrong started the day with a visit to the headquarters of the Livestrong charity he founded in 1997 and turned into a global force on the strength of his athletic dominance and personal story of surviving testicular cancer that had spread to his lungs and brain. About 100 Livestrong staff members gathered in a conference room as Armstrong told them "I'm sorry." He choked up during a 20-minute talk, expressing regret for the long-running controversy tied to performance-enhancers had caused, but stopped short of admitting he used them. Before he was done, several members were in tears when he urged them to continue the charity's mission, helping cancer patients and their families. "Heartfelt and sincere," is how Livestrong spokeswoman Katherine McLane described his speech. Armstrong later huddled with almost a dozen people before stepping into a room set up at a downtown Austin hotel for the interview with Winfrey. The group included close friends and lawyers. They exchanged handshakes and smiles, but declined comment and no further details about the interview were released because of confidentiality agreements signed by both camps. Winfrey has promoted her interview, one of the biggest for OWN since she launched the network in 2011, as a "no-holds barred" session, and after the voluminous USADA report - which included testimony from 11 former teammates - she had plenty of material for questions. USADA chief executive Travis Tygart, a longtime critic of Armstrong's, called the drug regimen practiced while Armstrong led the U.S. Postal Service team "the most sophisticated, professionalized and successful doping program that sport has ever seen." USADA did not respond to requests for comment about Armstrong's confession. Hein Verbruggen, the former president of the International Cycling Union, said Tuesday he wasn't ready to speak about the confession.