(NEW YORK) -- Lance Armstrong, formerly cycling's most decorated champion and considered one of America's greatest athletes, confessed to cheating for at least a decade, admitting on Thursday that he owed all seven of his Tour de France titles and the millions of dollars in endorsements that followed to his use of illicit performance-enhancing drugs.
After years of denying that he had taken banned drugs and received oxygen-boosting blood transfusions, and attacking his teammates and competitors who attempted to expose him, Armstrong came clean with Oprah Winfrey in an exclusive interview, admitting to using banned substances for years.
"I view this situation as one big lie that I repeated a lot of times," he said. "I know the truth. The truth isn't what was out there. The truth isn't what I said.
"I'm a flawed character, as I well know," Armstrong added. "All the fault and all the blame here falls on me."
In October, the U.S. Anti-Doping Agency issued a report in which 11 former Armstrong teammates exposed the system with which they and Armstrong received drugs with the knowledge of their coaches and help of team physicians.
The U.S. Postal Service Cycling Team "ran the most sophisticated, professionalized and successful doping program that sport has ever seen," USADA said in its report.
As a result of USADA's findings, Armstrong was stripped of his Tour de France titles. Soon, longtime sponsors including Nike began to abandon him, too.
Armstrong said he was driven to cheat by a "ruthless desire to win."
He told Winfrey that his competition "cocktail" consisted of EPO, blood transfusions and testosterone, and that he had previously used cortisone. He would not, however, give Winfrey the details of when, where and with whom he doped during seven winning Tours de France between 1999 and 2005.
He said he stopped doping following his 2005 Tour de France victory and did not use banned substances when he placed third in 2009 and entered the tour again in 2010.
"It was a mythic perfect story and it wasn't true," Armstrong said of his fairytale story of overcoming testicular cancer to become the most celebrated cyclist in history.
Armstrong would not name other members of his team who doped, but admitted that as the team's captain he set an example. He admitted he was "a bully" but said there "there was a never a directive" from him that his teammates had to use banned substances.
"At the time it did not feel wrong?" Winfrey asked.
"No," Armstrong said. "Scary."
"Did you feel bad about it?" she asked again.
"No," he said.
Armstrong said he thought taking the drugs was similar to filling his tires with air and bottle with water. He never thought of his actions as cheating, but "leveling the playing field" in a sport rife with doping.
Armstrong passed more than 500 drug tests during his career. In some cases, however, he was found to have used substances, including EPO, years after he retired when new tests could find previously untraceable drugs.
However, he denied a claim by former teammate Floyd Landis that he organized a cover-up and paid off officials when, in 2001, he allegedly failed a test prior to the Tour de Suisse.
Armstrong used his wealth and influence to go after any of his teammates or crew members who attempted to expose him. He sued a team masseuse and as well former teammate Frankie Andreu and his wife, Betsy Andreu, who claimed to have overheard Armstrong telling a doctor that he used multiple banned substances.
Armstrong said he believed he would not have been caught had he not come out of retirement in 2008, just after former teammate Floyd Landis was caught doping and stripped of the 2006 Tour de France title.
He said, however, that his "fate was sealed" when George Hincapie, the only teammate with whom he competed in all seven winning Tours de France, was forced to testify against him to USADA.
Minutes after the interview concluded, Livestrong -- the cancer foundation that he founded -- released a statement expressing disappointment in their former leader.
"We at the LIVESTRONG Foundation are disappointed by the news that Lance Armstrong misled people during and after his cycling career, including us. Earlier this week, Lance apologized to our staff and we accepted his apology in order to move on and chart a strong, independent course," the statement read.
"Our success has never been based on one person -- it's based on the patients and survivors we serve every day, who approach a cancer diagnosis with hope, courage and perseverance," it continued.
Also on Thursday, before the Winfrey interview aired, the International Olympic Committee stripped Armstrong of his 2000 Olympic bronze medal.
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