FITNESS instructors face a crackdown by councils, which are charging trainers for holding workout sessions in public parks.

At least three local authorities in Scotland – East Renfrewshire, East Lothian and North Lanarkshire – are asking commercial groups holding exercise classes in green spaces to apply and pay for a permit. Others are understood to be considering a similar policy.

The move has been welcomed by some industry experts, who claim it will prevent "cowboys" from setting up boot camps with little training.

But others have questioned how councils can police the scheme, and one instructor feared the charges were too high for small businesses set up to help people keep fit in a safe, group environment.

Donald MacGregor, who runs Scottish Military Fitness sessions in Kelvingrove, Bellahouston and Queens parks in Glasgow, said he was keen for a licensing scheme to be introduced.

He has met with Glasgow City Council to discuss the possibility of paying £50 per venue per month. A spokesman for the local authority stressed discussions were at a "very early stage".

Mr MacGregor said: "We have always campaigned for a licence because then you would be able to get rid of cowboys who are not operating properly.

"I'm willing to pay anything they want to charge me but they have to find out who is operating in the park and how they are going to police it. We need everybody to be batting from the same wicket."

The outdoor fitness industry has gone through a boom in recent years and almost every park now hosts boot camps, circuit classes and running groups.

Councils say the permits let them control the number of groups using parks and ensure instructors are trained and insured.

In East Renfrewshire and North Lanarkshire, fees depend on the number of participants and sessions. One group said it had been told it would be charged £500 a year to hold three classes a week in East Renfrewshire.

East Lothian charges £6.70 an hour, £25.60 for up to four hours and £50 for a full day.

One fitness instructor said it was a shame if small businesses were put off by the costs, "particularly at a time when we're supposed to be encouraging people to get fit and healthy".

But Andy McAllister, who runs Park Circuits in Glasgow, said permits were in place in parts of London, where the structure was "reasonably well priced".

He added: "I'm not into anybody training in parks if they are going to take away value, running over benches and damaging wildlife. But it has got to be fair.

"It is a bit disappointing if councils are looking at it just to get extra cash and without fully thinking it through."

Mr MacGregor questioned whether other groups using the parks would be asked to pay.

"The stipulation they have is if an organisation is making a profit from using the parks," he said. "But what about dog walkers? What about nurseries and schools?"

Edinburgh City Council requires professional dog walkers to sign a code of conduct requiring them to have public liability insurance and a spokeswoman said fitness groups may in future have to sign up to a similar scheme.

A spokeswoman for East Lothian Council said: "The fee covers the cost of facilities and booking allows us to ensure that their chosen area is available, that groups have the appropriate skills for the activities being undertaken, and that they have proper insurance, including public liability, in place."