Thank you all for your thoughtful and informative replies. Unfortunately, I can't handle the exercises. I am old and have gotten both feeble and brittle. I tried, gently to be sure, some moves I found on line. Now, in addition to the usual sharp arthritic pains I have in several joints, I have deep aches, almost like bruises, deep in the joints.
The best advice I'd have for anyone who is not old is 'get in shape, NOW'. Later will be harder.