Luckily don't suffer from Joint pains but do have an old injury to the knees. When they start playing up- It can get painfull and the best Remedy for me is to get out and ride. Still a bit of discomfort on the ride but If I do not exercise the Stiffness out- They will just sieze up completely. I find that walking helps a bit but that is boring.

Now starting on back pain- I do have this and the only way I can get comfortable is to ride. That stretched out position takes the load off the back and eases it completely.