Sponsors Nike, Anheuser-Busch and Trek dumped endorsement deals with Lance Armstrong on Wednesday as the doping-disgraced US cyclist stepped down as chairman of the Livestrong anti-cancer charity he founded. Trek, the company that made the bicycles Armstrong rode to seven Tour de France titles, announced Wednesday it was joining Nike and Anheuser-Busch in terminating its sponsorship contract with the disgraced rider. Armstrong was issued a life ban and stripped of his titles in August by the US Anti-Doping Agency (USADA), which last week revealed 1,000 pages of evidence against him, including testimony from 11 former teammates. "Trek is disappointed by the findings and conclusions in the USADA report regarding Lance Armstrong," a statement from the bicycle manufacturer said. "Given the determinations of the report, Trek today is terminating our long-term relationship with Lance Armstrong. Trek will continue to support the Livestrong Foundation and its efforts to combat cancer." In a statement earlier Wednesday, Nike expressed that "due to the seemingly insurmountable evidence that Lance Armstrong participated in doping and misled Nike for more than a decade", the sportswear giant decided to terminate their contract with him. And industry experts said Nike had no choice but to cut ties with Armstrong because it identifies itself with sporting excellence. David Carter, a sports business professor at the University of Southern California and executive director of USC's Sports Business Institute, said Nike could no longer afford to stand by Armstrong as it had other disgraced icons. "I think because his indiscretion cut to the very heart of competition in sport, if he lacks that kind of integrity there's no way a company like Nike can tolerate that," Carter said. Nike continued to stick with golf superstar Tiger Woods even as other sponsors dumped him in 2009 in the midst of a sex scandal that wrecked his marriage. Nike also supported NBA superstar Kobe Bryant when he faced a sexual assault charge in 2003, which was eventually dropped. NFL quarterback Michael Vick, vilified for his role in a dog-fighting ring, was dropped by Nike but re-signed after serving a prison sentence and resuming his gridiron career. "The other guys' problems were off the field of play," Carter said. Brewers Anheuser-Busch InBev, who used Armstrong in beer advertisements, said they would not renew a sponsorship deal with Armstrong when their current three-year endorsement contract ends in December. "We have decided not to renew our relationship with Lance Armstrong when our current contract expires at the end of 2012," said Paul Chibe, Anheuser-Busch vice president of US marketing. Both Nike and Anheuser-Busch said they would continue to support Livestrong, the charity Armstrong founded 15 years ago that has raised nearly $500 million. Armstrong stepped aside rather than see Livestrong impacted by the fallout from revelations that a doping scheme was at the heart of his Tour de France triumphs from 1999-2005, the worst scandal in a sport tarred by cheating. "To spare the foundation any negative effects as a result of controversy surrounding my cycling career, I will conclude my chairmanship," Armstrong said in a statement posted on the Livestrong website. Armstrong is set to attend a gala fundraiser on Friday in Austin, Texas, to celebrate Livestrong's 15th anniversary in what could prove to be an emotional moment in the public spotlight, his first since scandal details were revealed. "It has been a great privilege to help grow it from a dream into an organization that today has served 2.5 million people and helped spur a cultural shift in how the world views cancer survivors," Armstrong said. Carter said it was a move that was necessary if the charity was to continue its mission. "Obviously Livestrong will always be associated with Lance Armstrong, but he can't be the face of it," Carter said. "He understands that." More than 80 million of Livestrong's iconic yellow wristbands, launched in 2004 in collaboration with Nike, have been sold, donations that were in part inspired by Armstrong's now-tainted cancer comeback. Daniel Borochoff, president of the non-profit watchdog CharityWatch, agreed that Livestrong's future would depend on the organization distancing itself from the scandal. "What the organization needs to do is separate Lance Armstrong and all the charges of doping against him from the organization, and this helps to do it," he said. "The quicker they move away from him the better off they'll be." Borochoff's Chicago-based organization ranks Livestrong among its list of top-rated charities, based on criteria such as what percentage of the budget goes to programs. "A lot of charities started by sports stars don't amount to much... they can be poorly run -- this is a good one. This is a good organization," Borochoff said. However, the fact that it is so closely identified with Armstrong could put off potential donors, even though USADA's sanctions in August actually brought a spike in contributions. "When a scandal happens, reality starts to seep in later with some of these constant reports and 1,000 pages of documents and so forth -- people start to realize there is a problem here even if it was somebody's hero," Borochoff said. Carter noted that a surprising number of disgraced athletes manage to rehabilitate themselves in the eyes of fans and sponsors. Armstrong might be different, not only because he was already retired from top-flight cycling when he was banned but also because he has never admitted any wrongdoing. "The only way they come back is when they take personal responsibility and accountability for what they've done," Carter said. "He has not taken responsibility." Armstrong, who denies allegations of wrongdoing, chose not to fight the charges after losing a US federal court fight objecting to USADA's appeal process, saying he was weary from battling years of similar accusations. Armstrong had been an inspirational figure for millions after recovering from testicular cancer that had spread to his brain and lungs and then winning the world's most celebrated cycling event seven times in a row. USADA unveiled its evidence last week in a report to the International Cycling Union (UCI), which faces growing pressure to reveal how the 41-year-old American was able to escape detection for so long. UCI is considering the sanctions imposed by USADA. Rejecting them would likely set up a fight with USADA in the Court of Arbitration for Sport. Britain's Bradley Wiggins, this year's Tour de France winner, is among those trying to help healing cycling's shattered reputation, with his Sky team saying it will require all team members to sign a pledge they have never doped or be dropped from the squad. "We want a team in which riders are free of the risks of doping and in which fans -- new and old -- can believe without any doubt or hesitation," said a Sky statement. "We have been shocked by recent revelations of systemic doping in cycling's past. So we have taken steps to reaffirm our commitment to being a clean team." US federal agents looked into Armstrong for 18 months but closed their probe earlier this year without filing charges. But the unprecedented volume and detail of USADA's findings could lead US prosecutors and companies to consider fresh criminal and civil actions against Armstrong. "Lance Armstrong stepping down as chairman of the foundation and Nike dumping him were inevitable once the report came out," Ashley McCown, president of Solomon McCown, a Boston-based public relations firms specializing in crisis communications, told AFP by e-mail. "The findings in the report were too damning to ignore.... Lance is damaged goods and he should not expect any corporate sponsor to come knocking at his door any time soon."