@Danidl - BTW, as a fellow sufferer of night calf muscle cramps, you might be interested to hear that they reduce with use of Dioralyte - odd but true. Usually after a long walk, I'm woken by uncontrollable, horribly painful, persistent and prolonged spasming calf muscles, for which there is no relief for quite some time. In desperation I thought I'd try Dioralyte, after learning bodybuilders swear by it's anti-muscle cramping effects. Calf muscles haven't cramped since I've started using it.