Mate, good for you. Seems like you have been right in the wars me old mate? For what it’s worth my advice would be don't force yourself to do something just for the sake of it. However if it’s a positive and/or liberating experience and within your capabilities, go for it. You only live once. There’s nothing like raising the pulse and the old adrenaline levels for a bit of therapeutic rehabilitation? On a personal note, R or GT? Its a tester and one I am yet to resolve? Keep safe old mate.
It's the endorphins that I seek DC, don't we all?
There's nothing better (well almost, if you know what I mean!), than getting on your bike and going for a ride when the roads are dry, the suns out and your heads in the right place, but you are right we also have to take note of what our bodies are telling us, increasingly so.
Stay safe down there