Is there not a gym in Davids Road?
The plans for the new pool, which we hope will eventually be built, would include gym / fitness equipment and hopefully other facilities as well if there is room and money. With this coming in the next 5-10 years it will discourage anybody else opening up a gym in the immediate area.
If somebody did want to open a gym there are a couple of possible locations. Heron House has a couple of empty floors and the old post office could be converted, although it might be a bit small.
In the meantime, perhaps you could help Johnc by transporting raw meat over Canonbie hill.