Frank Bruno has criticised the way people with mental illnesses are being treated by the NHS, saying that many are "needlessly suffering".
The former world heavyweight champion has launched a new campaign calling for changes to be made in the way patients are cared for.
Bruno, who has Bipolar Disorder and has been sectioned twice, says he wants to use his experiences to make sure others are treated in a better way.
The 50 year-old, an ambassador for mental health group, Rethink, said: "Being in hospital did not make me better, it just made me worse.
“In hospital people with mental health illness are encouraged to take their medication, lie down and keep quiet.
"I’d just like to ask people in charge of our mental health care what’s wrong with exercise and people moving around.
“When I was in hospital I am afraid to say a lot of the doctors and nurses simply weren’t interested enough in the patients.
"Some just didn’t give a s---. They turned up, got paid and went home.
“But the doctors and nurses need to remember the people they are dealing with are at a point of crisis in their lives.
"They need someone to talk to, to help them through – not just give them their drugs and show them back to bed.”
Bruno says he has concrete ideas on what changes need to be made, which he will be outlining in detail when he sits down with a senior Government minister.
He hopes that by speaking out about his own problems more people in similar situations will come forward to get help as official statistics have shown that one in four people will suffer from some mental health problems in their lives.
“I am determined to do all I can to help because I have seen the problems which are there in the service," he told the Mirror.
"I just want the opportunity to show people how we can make changes to the way these horrible illnesses could be treated.
“If I could help one person to not have to go through what I have been over the past 10 years then I would be happy.”
The Department of Health have responded to Bruno's invitation and said they were prepared to listen about his experiences and see if any lessons can be learned.