Paula Radcliffe has said she is "devastated that my name has even been linked" to wide-ranging accusations of cheating in sport.
The marathon world record holder issued a strongly worded statement after MPs on the Culture, Media and Sport Select Committee began an investigation into blood doping in athletics.
Committee chairman Jesse Norman was questioning David Kenworthy, chairman of UKAD, the UK's national anti-doping agency, when he seemed to raise suspicions about a prominent British marathon runner.
He asked Mr Kenworthy during the House of Commons hearing: "When you hear that the London Marathon, potentially the winners or medallists at the London Marathon, potentially British athletes are under suspicion for very high levels of blood doping.
"When you think of the effect that has on young people and the community nature of that event, what are your emotions about that, how do you feel about that?"
Mr Kenworthy said: "I think it is a tragedy if you and I are looking at a sporting event with a degree of cynicism about what we are seeing . I think it is our role to overcome that cynicism."
Radcliffe, 41, immediately hit back by issuing a statement saying: "I categorically deny that I have resorted to cheating in any form whatsoever at any time in my career, and am devastated that my name has even been linked to these wide-ranging accusations."
The hearing was set up after Dr Michael Ashenden helped produce a controversial analysis which suggested the International Association of Athletics Federations (IAAF) had turned a blind eye to hundreds of suspicious blood tests.
The claims by German broadcaster ARD and The Sunday Times appeared last month.
Radcliffe said: "I have campaigned long and hard throughout my career for a clean sport. I have publicly condemned cheats and those who aid them. These accusations threaten to undermine all I have stood and competed for, as well as my hard earned reputation. By linking me to allegations of cheating, damage done to my name and reputation can never be fully repaired, no matter how untrue I know them to be.
"Whilst I have the greatest of respect for anyone responsibly trying to uncover cheating in sport, and of course for Parliament itself, it is profoundly disappointing that the cloak of Parliamentary privilege has been used to effectively implicate me, tarnishing my reputation, with full knowledge that I have no recourse against anyone for repeating what has been said at the committee hearing."
The Sunday Times said it had gained access to a database containing more than 12,000 blood tests from 5,000 athletes, and that more than 800 individuals - and a third of medallists in endurance events at Olympics and World Championships between 2001 and 2012 - had suspicious blood test results which were not followed up by the IAAF.
Radcliffe said she had "wrestled long and hard with a desire to speak out with the true facts" concerning her results when the Sunday Times story broke but speaking about it then would have only fuelled false speculation.
She said: "I was made aware that I would be facilitating mass coverage of my name in connection with false allegations of possible doping, which would enable further irreparable damage to be done to my reputation. As a result of today's parliamentary hearing I can no longer maintain my silence."