David Flowe said he doesn't care if Armstrong was involved in doping or if he even confesses to it.
"The man is an inspiration for those battling cancer," he said. "Quit being so judgmental of others especially someone who has done so much good for the world!"
Armstrong, 41, has been an icon for his cycling feats and celebrity, bringing more status to a sport wildly popular in some nations but lacking big-name recognition, big money and mass appeal in the United States.
He fought back from testicular cancer to win the Tour de France from 1999 to 2005. He raised millions via his Lance Armstrong Foundation to help cancer victims and survivors, an effort illustrated by trendy yellow "LiveSTRONG" wristbands that helped bring in the money.
Before the interview with Winfrey, the disgraced cycling legend apologized to the staff of his cancer charity, a publicist for Livestrong Foundation said.
Armstrong was tearful during the 15-minute meeting and didn't address the issue of steroid use in cycling, said Rae Bazzarre, director of communications for the foundation.
Bazzarre added that Armstrong offered to the staff a "sincere and heartfelt apology for the stress they've endured because of him."
He urged them to keep working hard to help cancer survivors and their families.
Banned for life
The USADA hit Armstrong with a lifetime ban after the agency issued a 202-page report in October that said there was overwhelming evidence he was directly involved in a sophisticated doping program.
The report detailed Armstrong's alleged use of performance-enhancing drugs and blood transfusions. The USADA said it had tested Armstrong fewer than 60 times and the International Cycling Union conducted about 215 tests.
"Show one failed test, just one," Ron Berg said, challenging the wave of public opinion against Armstrong. "You can't, because he passed them all. ... They hate him for his success and tried to fail him, they could not."
The agency did not say that Armstrong ever failed a test, but his former teammates testified as to how they beat tests or avoided them altogether.