Two-time Tour de France stage winner Robbie McEwen of Australia said he could never forgive Armstrong, adding he "deceived everybody on the planet, us included."
World Anti-Doping Agency president John Fahey told The Associated Press in a telephone interview that Armstrong's assertion in the interview that he wasn't cheating when he took part in doping through his seven Tour de France wins "gives him no credibility."
Tennis' top-ranked player Novak Djokovic was even more succinct in his judgement, telling reporters at the Australian Open in Melbourne that Armstrong "should suffer for his lies all these years."
Speaking from Adelaide ahead of the pro tour-opening Tour Down Under, McEwen and fellow-riders were just as deceived as the public.
"We wanted to believe, like everybody, that the Tour (de France) was clean. We're all athletes out there suffering through the mountains and you like to think he was just training harder and working harder than we all were," McEwen said.
Armstrong told said in the interview with Oprah Winfrey that he "looked up the definition of cheat ... and the definition is to gain an advantage on a rival or foe. I didn't view it that way. I viewed it as a level playing field."
Fahey said that rationalization was not plausible.
"He was wrong, he cheated and there was no excuse for what he did," Fahey told The AP. "If he was looking for redemption, he didn't succeed in getting that."
McEwen also rejected Armstrong's justifications of his actions.
"The problem with people like Lance, or any other dug cheat, is that they think everyone else is doing it so they have to do it," he said. "In fact not everyone else is doing it."
McEwen was heartened that Armstrong's explanation of how he evaded detection for so long is a feat difficult to replicate in today's anti-doping environment.
"One of the big changes that has been made is the introduction of the biological passport and the whereabouts system, and that has made it, I would say, virtually impossible for this kind of thing to happen again," he said.
Fahey said that there was no doubt that drug-testing had improved markedly since Armstrong won the Tour de France from 1999 to 2005. Armstrong retired for two years before making a comeback in 2009, and the WADA code for drug testing adopted by most countries was instituted just before the 2004 Athens Olympics.
"Some of them (drug tests) may have been ineffective back then, but that has changed," he said.
Not everyone wanted to discuss Armstrong's confession, with many of the teams gathered in Adelaide remaining tight-lipped as they digested the interview and its implications.
Most riders and team directors contacted by the AP generally refused comment on Friday's interview.
Armstrong's former mechanic and personal assistant Mike Anderson however, who had to battle legal action after accusing Armstrong of drug use, couldn't bring himself to watch Friday's interview.
Texas-born Anderson settled in New Zealand after being fired from Armstrong's personal staff in 2005. In 2010 he told Sports Illustrated that while helping Armstrong clear out an apartment he shared with his former girlfriend in Spain he found a box labeled Androstenedione, a banned steroid.
Anderson said he took no satisfaction on Friday that Armstrong had finally admitted that he was the liar and that those he had accused of lying were telling the truth.
Stuart O'Grady, a 2004 Olympic gold medalist who has worn the Tour De France yellow jersey on two occasion, said while he was disappointed and let down by Armstrong's actions he was hopeful the eventual confession could be a healing influence for cycling.
"As much as it's been shocking for the cycling world, it's cycling that's suffered for years so hopefully through Lance's confessions we can start looking to the future and something good can come out of this," O'Grady said.
"The damage has been done, but what we can do now is look to the future. ... It's a great sport. It's our lives, not a hobby and it isn't going anywhere."
Djokovic said Armstrong's actions and now admissions meant he had "lost a lof of faith in cycling."
"It's a disgrace for the sport to have an athlete like this," Djokovic said after winning at the Australian Open on Friday.
"He cheated the sport. He cheated many people around the world with his career, with his life story. They should take all his titles away because it's not fair towards any sportsman, any athlete. It's just not the way to be successful."