(NEW YORK) -- Amid mounting evidence that he allegedly used performance-enhancing drugs, Lance Armstrong announced on Wednesday that he was stepping down as the chairman of Livestrong, his cancer-fighting foundation.
In a statement, the cyclist said he came to his decision "to spare the foundation any negative effects as a result of controversy surrounding my cycling career."
Just last week, the U.S. Anti-Doping Agency released a report in which 11 of Armstrong's former teammates allege they helped him take performance enhancing substances.
The USADA, which banned Armstrong for life from professional competition and stripped him of his seven Tour de France titles, went on to say that Armstrong, his coaches and teammates "ran the most sophisticated, professionalized and successful doping program that sport has ever seen."
Livestrong Vice Chairman Jeff Garvey will take over as the foundation's chairman, Armstrong said.
Meanwhile, in other news, Nike announced on Wednesday that it has terminated its contracted with Armstrong.
In a statement, the sports apparel giant said: "Due to the seemingly insurmountable evidence that Lance Armstrong participated in doping and misled Nike for more than a decade, it is with great sadness that we have terminated our contract with him. Nike does not condone the use of illegal performance enhancing drugs in any manner."
Nike added that it still plans to support Livestrong initiatives "created to unite, inspire and empower people affected by cancer."
One of Armstrong’s other partners, the apparel company Oakley, says that it will stand with Armstrong for now: “As we have stated in the past, Oakley does not approve in any way the use of illegal substances for enhancing performance in sports. Our policy with our athletes is to support them until proven guilty by the highest governing body of sport or court of law. We are reviewing the extensive report from the USADA, as well as our relationship with Lance, and will await final decision-making by the International Cycling Union."
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