Fortunately for me, my leg cramps are only occasional, so I haven't searched much for the root causes. Maybe less hydration that day, or more exercise?? Mostly, it seems, just being an old codger. But what always works for me, and others I've shared this info with, at the first hint of a cramp building, sit up and pull your big toe (cramping leg, of course) back towards your head, as hard as possible. If necessary, my other-side heel can do the toe bending instead of my hand. If done during the brief build-up phase, no cramp occurs. If I'm late, it stops the cramp (but residual pain continues for awhile). I don't see that very easy "cure" mentioned in this forum. No meds. No equipment. I cannot recall who shared this with me decades ago, and it always astounds me that it's not more widely known and practiced. Of course, some cramp causes are probably resistant to this simple treatment. Condolences to those who fall into that group. But "ordinary" cramps -- like from making it all the way to senior citizenship -- seem to respond for everyone I've shared this with. Sincere best wishes to all sufferers.