I got a membership to the hospital gym from my GP, it didn't work out too well for me because the facilities weren't that great and it was quite a way for me to travel, so I ended up going to a new gym and paying anyway
I think they may be able to give half price memberships at certain gyms, I think that may have been an option when I asked but then my BMI is in the highest possible part of the scale so it is probably BMI dependant, perhaps lower if you have co morbidities such as diabetes or heart disease.
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