I have arthritis in my hands. I (like Barry) take the supplements and also I take Naproxen (Aleve).
As far as exercise, my hands probably get enough of that w/ woodworking.
For me, my big problem is ganglionic cysts. If the problem gets worse (which it hasn't so far) - I will go to the hand surgeon and he (or she) will shave off the bone spurs from the arthritis. I am resisting that notion.