Regarding Cramps: I have the tightness in hand, arm, leg and many times shoulders. For years my wife has been doing fascia blasting. she said let me do this to your hand and the relief was remarkable. She then did my shoulders and leg again it helped greatly. Now this is NOT a permanent fix, but it does provide relief for me. Look into this fascia blasting thing it helps me. Oh, and sometimes it does hurt but the relief is real.
I did also save up money to get her a small motorized "blaster" and that works even better. Yes, it was a present for her---but hey she's great and doesn't mind sharing.