Cyclist Lance Armstrong admitted to doping during an interview with Oprah Winfrey on Monday, the talk-show host said Tuesday. Winfrey said, “We were mesmerized and riveted” by Armstrong’s answers. “He did not come clean in the manner I was expecting.” Armstrong reportedly plans to testify against cycling officials who allegedly knew about his drug use. Armstrong also is believed to have issued a mea culpa to the staff of his charity, Livestrong, and called members of the cycling community to apologize for allegedly lying and misleading them. Winfrey also announced the interview had been spread over two nights, and will now air Thursday and Friday.