The Comber Greenway is a popular recreational area in east Belfast
A group of GPs in east Belfast have asked Transport Minister Conor Murphy to reconsider developing a rapid bus transit line along the Comber Greenway.
The 25 doctors said they feared the greenway could be damaged if the bus system goes ahead as planned.
They have written to Mr Murphy asking him to reconsider the plan.
Spokesman John Kyle said the greenway was a popular resource which provided significant health and environmental benefits to the area.
"The greenway has been a huge success in east Belfast and the residents here really have enjoyed it enormously and benefitted from it enormously," he said.
"Given the fact that we are facing what people talk about as an obesity and diabetes time bomb, and the need to integrate exercise into our lifestyle, this seems to us an ideal incentive to encourage people in east Belfast to be more active.
"The Department of Regional Development describe the greenway as seven miles of traffic free tranquillity, if you have buses racing up and down then it loses a huge amount of its attractiveness and its benefit."
A spokeswoman for the department said a report by independent consultants in 2008 had recommended the greenway route as the best place to develop the transit line.
"Rapid transit division within the Department for Regional Development are currently moving into the preliminary design stage of the project and are examining all the route options to confirm the findings of the strategic outline case," she said.
"At present they are carrying out the necessary on-site surveys.
"The preliminary design plans will form the basis of the public consultation stage when everyone will have an opportunity to view the design and raise any concerns they may have."