WEDNESDAY, Oct. 17 (HealthDay News) -- A week after the release of more allegations of involvement in illegal blood doping in professional cycling, Lance Armstrong announced Wednesday that he is stepping down as chairman of LIVESTRONG, the cancer charity he founded.

In a statement posted on the foundation's website, Armstrong said, "I have had the great honor of serving as this foundation's chairman for the last five years, and its mission and success are my top priorities. Today, therefore, to spare the foundation any negative effects as a result of controversy surrounding my cycling career, I will conclude my chairmanship."

He said that LIVESTRONG Vice Chairman Jeff Garvey will take over as chairman.

The scandal over Armstrong's alleged involvement in doping continues to swirl around the seven-time Tour de France winner. On Oct. 10, the U.S. Anti-Doping Agency accused Armstrong of being a ringleader in a long-term doping conspiracy within professional cycling. According to The New York Times, 26 people, including nearly a dozen of Armstrong's teammates on the U.S. Postal Service team, have submitted sworn testimony detailing their own doping and his involvement in the practice.

"The U.S.P.S. Team doping conspiracy was professionally designed to groom and pressure athletes to use dangerous drugs, to evade detection, to ensure its secrecy and ultimately gain an unfair competitive advantage through superior doping practices," the anti-doping agency said. "A program organized by individuals who thought they were above the rules, and who still play a major and active role in [the] sport today."

Armstrong has consistently denied doping and, through his spokesman, told the Timesthat he had no comment on the agency's statement.

Armstrong's well-publicized battle with testicular cancer was the impetus for LIVESTRONG, which has been very successful in advocating for cancer research.

"Long before he became a household name, Lance Armstrong created a foundation to serve others facing the same fears and challenges he struggled to overcome as a result of his cancer diagnosis," Doug Ulman, LIVESTRONG president and CEO, said in the foundation's news release. "Today, thanks to Lance's leadership, that foundation has had the privilege of raising close to $500 million to serve people affected by cancer."

As for Armstrong, he said in the statement that "my family and I have devoted our lives to the work of the foundation and that will not change. We plan to continue our service to the foundation and the cancer community. We will remain active advocates for cancer survivors and engaged supporters of the fight against cancer."

More information

There's more on testicular cancer at the American Cancer Society.