Athletes have "lost faith" in their governing body after a report said "corruption was embedded" within the IAAF, said British runner Jo Pavey.
The European 10,000m champion questioned whether the sport can police itself with the IAAF accused of helping to cover up doping in Russia.
"As athletes at the moment we've all lost confidence in the IAAF," she said.
But she joined former British athletes including Paula Radcliffe and Roger Black in backing president Lord Coe.
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A report commissioned by the World Anti-Doping Agency and released on Thursday was heavily critical of the organisation, but author Dick Pound said he "could not think of anyone better" than Coe to lead reform.
Admitting the IAAF - the International Association of Athletics Federations - was a "failed organisation" and that the sport was at a crossroads, 59-year-old Coe said: "We have to make sure we redouble our efforts to be very clear with people that we are not in denial."
World marathon record holder Radcliffe believes the 2016 Rio Olympics will be cleaner than the London Games four years ago, while 1996 Olympic 400m silver medallist Black believes the sport can move forward.
But fellow former British athlete Kriss Akabusi questioned how Coe, who was vice-president for eight years before taking over from the shamed Lamine Diack, could not have known about the extent of systematic doping.
"I find it very difficult for Lord Coe to say he's got absolutely no clue," said the ex-400m runner, who won two bronze medals at the 1992 Olympics.
"The only way is if a vice-president is in a titular position that has no real contact with the sport."
Key points from probe into 'corrupt' IAAF
- Former IAAF president Diack was "responsible for organising and enabling the conspiracy and corruption that took place in the IAAF".
- Diack sanctioned the fraud and the extortion of athletes carried out by the actions of the illegitimate governance structure he put in place.
- The corruption was "embedded" in the IAAF. "It cannot be ignored or dismissed as attributable to the odd renegade acting on his own," the report says. It was "increasingly clear" that far more IAAF staff knew about the problems than has so far been acknowledged.
- There was "no appetite" from the IAAF to deal with the problems, said Pound.
- The IAAF Council, which included Coe, "could not have been unaware of the extent of doping in athletics".
- Coe's right-hand man, Nick Davies, who stepped aside from his role as the director of the president's office last month, was "well aware of Russian 'skeletons' in the cupboard".
- Pound recommends a "forensic examination" of the processes behind the awarding of the 2021 World Athletics Championships to Eugene in the United States.
'It goes so much deeper than Russia'
Pavey, 42, aims to compete at the Olympics for a fifth time later this year but described the report as "absolutely devastating".
"As athletes at the moment, we've all lost confidence in the IAAF and we don't trust them to police our sport as far as anti-doping and looking after the interests of clean athletes," she said.
"It's a frustrating time and it makes you want to call for something independent, where the sport isn't policing itself on anti-doping issues, because I think we've lost a lot of faith.
"I think it's going to take longer than until Rio to restore faith. There's been action taken against Russia, but it goes so much deeper than Russia."
Russia's athletics federation was provisionally suspended from international competition, including the Olympic Games, in November for its alleged involvement in widespread, "state-sponsored" doping.
Despite her concerns about the organisation itself, Pavey believes Coe can help bring about change.
"It's an opportunity for him to turn it around, he's passionate about taking our sport forward and hopefully we can look forward to a brighter future," she said.
'We are a failed organisation' - Coe
Coe has the task of rebuilding trust in athletics while facing questions over why he did not know about the scandal that was unfolding while he was vice-president.
On Wednesday, he said there had been no "cover-up", yet Pound clearly indicated there had been, although he insisted he did not believe the double Olympic 1500m champion had lied.
"There are no tomorrows for athletics, we are at a crossroads," Coe said, calling for the sport to move on from the "horror show".
Coe apologised if his language had occasionally been "clumsy" and said he understood the seriousness of the situation.
"The overall issue about whether or not we are in an organisation that has failed, I tell you we have," he said.
"I know that. We are a failed organisation.
"I'm sorry if my language has in any way demonstrated a sort of a lack of understanding about the depth of this."
Speaking to BBC Radio 5 live, Akabusi said Coe needed people alongside him who would challenge his own thinking, adding: "Lord Coe will be looking at it as a chance for a new start. The sport can't get any lower, can it?"
Radcliffe warned against blaming Coe for the current crisis, suggesting he might consider walking away if criticism of him persisted.
"If we attack and attack, then he might say it is not worth it," she said. "It is then athletics' loss."
The views around athletics
Paula Radcliffe, Women's marathon world record holder
"It is extremely damaging but extremely good that this has come to light and is not still going on in the background.
"Athletes in Rio will be taking part in a much cleaner Olympics than London 2012 was.
"We have to move forward from this, restore integrity and the ability of the public to watch athletics and believe in what they are seeing."
Roger Black, 1996 Olympic 400m silver medallist
"It's another bad day for athletics, but hopefully we can really look forward now and the majority of people believe Seb Coe is the right man to do the job.
"We're British so there is a degree of bias here, but who else would do this job? The sport is in an absolute mess, though, and it has to be done rigorously and properly to turn it round and it's going to take a long time."
Darren Campbell, 2004 Olympics 4x100m relay gold medallist
"First and foremost, we have to root out all that rot and restore the public's faith in the sport. We have to involve the public.
"Lord Coe has to restore the faith. He is the man at the top."
Craig Reedie, Wada president
"It is hugely disturbing that individuals at the highest levels of the IAAF were abetting and covering up doping for their own financial gain.
"This flagrant disregard for the law and anti-doping rules undermines trust amongst clean athletes, and indeed the public, worldwide.
"Given their criminal nature, the actions of these individuals are now in the hands of the French justice system."