Britain's Olympic heavyweight champion Audley Harrison last night suggested that many boxing trainers knew little about how to regulate their fighters' weight as they prepare for championship fights, and that dehydration is the principle reason why boxers suffer major health problems.

Although no one has confirmed that Paul Ingle suffered significant difficulties making the nine stone featherweight limit for his International Boxing Federation title defence against South African Mbulelo Botile in Sheffield on Saturday, Harrison said Ingle looked "drained" even before the fight began.

Ingle is receiving intensive care in Sheffield's Royal Hallamshire hospital, where he remains in a sedated coma following emergency surgery to remove a blood clot on his brain after he was knocked out in the 12th round of his fight.

There has been widespread criticism of Ingle's corner, his trainer Steve Pollard and manager Frank Maloney, for allowing their exhausted fighter to go into the last round, after being knocked down in the 11th, but Harrison hinted the damage might have been caused by Ingle's preparations.

"In a year's time we may be saying this was just an isolated incident. But Paul didn't look strong. Trainers have to realise they must bring fighters' weight down gradually.

"Dehydration is something that all fighters and trainers have to understand. I don't know of a heavyweight ever having problems of this sort. They never have to worry about their weight, and never get brain injuries like this.

Harrison (29), who is having further talks with the BBC to discuss his likely professional debut in April, nevertheless defended Ingle's corner for not pulling their fighter out.

"Paul built his career on a warrior's style: digging deep, no retreat, no surrender. When he hopefully gets better, Paul Ingle will say that's my style and I didn't want them to pull me out."

But the world's number one amateur, whose win in Sydney brought Britain its first Olympic boxing gold medal since 1968, said he had not been put off from turning professional.

"The risks are you can go in the ring and loose your life. It's something we're all fully aware of. It makes you question your desire. I've had 20 plane journeys in the last two months, but if a plane before mine crashes, I'll still get on the next one to reach my destination. And my destination is to be heavyweight champion of the world."

Harrison maintains the sport cannot be made any safer and said: "We have these blips in the sport and I hope Paul makes a full recovery.

"But really when you compare this issue and Spencer Oliver a few years ago, then statistically boxing is a very safe sport.

"If you compare how many boxers become injured in comparison to other sports then you really have to say, although there is a risk involved and the boxer could lose their life, statistically the risks are very few and far between."

As an amateur Harrison was required to wear a headguard when he fought in Sydney in the summer. Some believe if fighters wear headguards it will avoid a repeat of another Ingle situation, but Harrison does not agree.

There are calls for fighters to wear headguards again - but Harrison does not believe the equipment will prevent serious injuries happening in the ring.

He told BBC Radio 5 Live: "Statistics actually show that headguards, while stopping superficial injuries like cuts to the head, don't prevent you from getting knocked out.

"You still get knocked out in amateur boxing like you do as a professional. So really the headguard is really there to satisfy the public image, but in terms of safety it's actually quite questionable. That's my argument for not bringing headguards into the pro game."