This question has been asked so many times its getting out of hand.. Please check other threads, use the search option etc etc.. this is going to be locked and stickied so people can see it!
Edit (by Admin): Yeah, I'm with crawty on this one - and any such threads / questions belong in the LOCAL forums, not the main UK ones. Soemone in Yorkshire isn't going to know about gyms in Tyne and Wear. Ask your locals!