Ending years of denial, champion cyclist Lance Armstrong has formally admitted he cheated his way to his record seven Tour de France titles.

Now, many who once supported the athlete are outraged.

Journalist Pierre Ballester, co-author of 'L.A. Confidential: Lance Armstrong's Secrets' said even now he thinks Armstrong is withholding some truth.

"To me he even lied because when he said he went back in 2009 on Tour de France he said he never doped. On the USADA survey they just said the contrary."

Pierre Bordry, the former head of the French anti-doping agency, agreed the confessions didn't go far enough.

He wants more details about how the doping occurred in order to rescue the reputation of cycling as a sport.

And former Armstrong masseuse Emma O'Reilly, who tried to expose Armstrong's doping in 2003 but was sued by him for her efforts, wants a full out apology.

"One part of me was like, 'this is great', but the other part was 'you know what, the little runt'. I wanted to hit him across the head, drag him up to Manchester to apologise to people close to me, and eyeball them and apologise to them."

But she said she had no plans to sue.

Armstrong described himself as a "flawed character" when confessing his doping to Winfrey, but said he had never considered himself to be a cheat.