NATIONAL NEWS (CNN) — Former pro cyclist Lance Armstrong will step down as chairman of the Livestrong cancer charity he founded in 1997 after recovering from the disease, organization spokeswoman Katherine McLane said Wednesday.
The move comes the same day that Nike, a key Armstrong sponsor, announced it was ending its contract with Armstrong amid "seemingly insurmountable evidence" that he participating in doping.
Armstrong said his decision was made to "spare the foundation any negative effects as a result of controversy surrounding my cycling career," according to a statement posted to the group's website.
Last week, the U.S. Anti-Doping Agency said it had uncovered overwhelming evidence of Armstrong's involvement in a sophisticated doping program while a professional cyclist. Armstrong has consistently denied the claims.
Nike said it would continue to support Livestrong initiatives.
Founding chairman Jeff Garvey will take over for Armstrong, the Texas-based organization said.
Armstrong said that he and his family would "continue our service to the foundation and the cancer community," but didn't specify in what role.
Armstrong founded the charity after his own treatment for testicular cancer that had spread to his brain and lungs. He came back from the disease seemingly stronger than ever, winning the first of his seven Tour de France titles three years after he was diagnosed with cancer.
His success became an inspiration for cancer patients worldwide, spreading his reach far beyond the insular world of cycling and cementing a place in celebrity culture, dating a rock star and appearing in movies. The bright yellow "LIVESTRONG" wristbands distribute by his charity became a potent symbol for perseverance in the face of adversity.
People should look to that legacy in assessing Armstrong, Livestrong President Doug Ulman said in praising the charity's founder.
"Lance's devotion to serving others whose lives were irrevocably changed by cancer, as his was, is unsurpassable," he said in the statement. "We are incredibly proud of his record as an advocate and philanthropist and are deeply grateful that Lance and his family will continue to be actively involved with the Foundation's advocacy and service work."
In its report, the anti-doping agency made public testimony from Armstrong's teammates and others involved in the U.S. Postal Service- and Discovery-sponsored cycling teams who said the seven-time Tour de France winner was among team members who used banned performance-enhancing substances and tried to hide it from testing officials.
Armstrong has said he never has failed a drug test and has consistently denied participating in any banned practices. Armstrong's lawyer, Tim Herman, called the report last week a "one-sided hatchet job" and a "government-funded witch hunt."
Last week, Ulman also defended Armstrong against the doping charges, issuing a statement saying USADA appeared to be "motivated more by publicity rather than fulfilling its mission." In that October 10 statement, he lauded Armstrong for his achievements "both on and off the bike."
McLane also noted the day of the report's release that donations to the charity had boomed since August, when Armstrong announced he was ending his legal fight to stop USADA's investigation.
According to Livestrong, Armstrong has helped raise nearly $500 million for cancer research, treatment and support in his role as Livestrong founder and helped "dispel the stigma and misconceptions about the disease."
-- CNN's Danielle Dellorto contributed to this report.