FORTUNE — Fifteen years ago, Lance Armstrong launched one of the most successful nonprofit organizations to address the needs of people affected by cancer. Since then, Armstrong’s Livestrong Foundation has raised more than $470 million to help more than 550 organizations conduct cancer survivorship research or offer services to people affected by cancer.
That doesn’t include a big win Armstrong helped score for the foundation’s home state of Texas, where voters passed a referendum guaranteeing $3 billion in funding for cancer research.
So what happens now that there’s egg all over the public face of such a prominent athlete and cancer survivor who’s also built a business as an ambassador for global brands like Nike (NKE)?
As is the case with many a disgraced public figure, we should expect things like a tell-all book, a movie deal, and other income-producing endeavors that take full advantage of an attempted return to glory. For now though, stripped of all of his Tour de France titles, an Olympic bronze medal, and all of his brand sponsorships, Armstrong has hit career rock-bottom. He’s been exposed for using performance-enhancing drugs and some of his former teammates say that they were bullied by Armstrong to take them as well. He will need to put in a lifetime’s worth of diligent image rehab.
But it may not be the doping scandal that’ll prove hardest on Armstrong’s reputational comeback. Karen Friedman, author of Shut Up and Say Something: Business Communication Strategies to Overcome Challenges and Influence Listeners, argues that Armstrong’s repeated failure to take ownership of lying and cheating “causes a huge credibility problem” that may not be easily swept away by apologizing with Oprah Winfrey. “Over time, people tend to forgive, but not forget,” she says.
Then again, plenty of shamed high-profile personalities have found their way back into the hearts of fans and scored endorsements again. Take Kobe Bryant, whose reputation took a major nosedive after being accused of rape in 2003. “After his criminal troubles ended, he immediately resumed his on-court triumphs, access to reporters, and charitable work, while avoiding any further trouble,” says Jim Moorhead, author of The Instant Survivor: Right Ways to Respond to When Things Go Wrong. Years later, Bryant is a success both on the court and as the face of Sprite, McDonalds (mcd), Nike, Adidas, and other brands.
Armstrong’s competitive nature, which led him astray, might also help accelerate his path back into the public’s good graces, much like Michael Milken. The notorious former “junk bond king,” who went to federal prison for securities fraud in the early 1990s, is a cancer survivor like Armstrong. Milken devoted his considerable influence and wealth to cancer research, prompting a 2004 Fortune feature story proclaiming Milken as “The Man Who Changed Medicine.”
In the days following his Oprah appearance, “Armstrong must show whatever good comes from this week was not simply a one-time event managed by his lawyers and communications advisers,” says Erin Powers of Houston-based communications firm Powers MediaWorks. Armstrong will have to display patience and commitment to maintain good behavior going forward while legal challenges may make candor and full disclosure more difficult.
Perhaps the most courageous thing Armstrong could do next would be to speak out publicly against doping in sports. “He can do that in so many ways,” says Andy Tannen, senior vice president and director of Strategy and Development at MSL New York, a global public relations firm. “Through public speaking to young athletes and students and writing a book that explains why he did it and why it is wrong.”
Staying away from racing would also cement the fact that his apology was to publicize his regret and not to get back into competition, says George Sopko, vice president of Stanton PR & Marketing in New York. A self-imposed ban from competing publicly may be a high hurdle for Armstrong to jump, although it may be unavoidable if he wants to refocus the public’s attention towards his philanthropy and away from the doping scandal.
“Apologies are promises to change,” says Nick Smith, a professor of philosophy at the University of New Hampshire and author of I Was Wrong: The Meanings of Apologies.
“Like promises, we cannot judge them fully in the moments they are spoken.” Wrongdoers need time to search for their deepest values and to begin rebuilding their lives with habits that honor those principles. “This sort of persistent growth creates good people. Moral development does not occur within a news cycle.”
Harrison Monarth is the founder of GuruMaker–School of Professional Speaking. He’s also the author of The Confident Speaker and Executive Presence.