Chris Boardman, the former Olympic cycling champion, said the move would be better for tackling obesity than giving out gym passes.
Doctors can already write prescriptions for obese people to go to exercise classes.
But Mr Boardman – who won a gold medal in the 1992 Olympics – said forcing people to go to the gym put people off taking exercise.
He told the Sun: ‘The problem with those solutions is that they bolt on to your life so they’re a chore.
‘If you can build an activity almost subconsciously into getting around then it happens organically. And that’s sustainable.
Chris Boardman won a gold medal in the individual pursuit in the 1992 Olympics in Barcelona
‘If I want to go to the gym I come in some nights and I’m tired and I can’t be bothered. If when I come in I’ve just done three or four miles home, I’ve already done my exercise.
‘The vast majority of journeys in this country are less than five miles. Thirty per cent are less than two miles and still the preference is to make them by car.
‘So if it becomes part of the fabric of my life I’m going to do it.’
He added: ‘The Department of Health should be screaming at the top of its voice and banging on doors saying for God's sake if people want to ride bikes, get everything out of their way and we’re all going to benefit.’
Tam Fry, of the National Obesity Forum, backed Mr Boardman’s idea. He said cycling would help overweight Brits keep their weight down.
Mr Fry said: ‘Bicycling helps all the muscle groups. It is a brilliant exercise - but it has to be done responsibly. GPs will have to make sure patients have had the right training and wear helmets.’
Mr Boardman, one of British Cycling’s star advisors, has urged ministers to commit to spending £10 a person every year on improving cycling safety