What Causes Recurrent Cramps In The Legs?

Good morning, i am 57yrs old , a type 2 diabetic,a recent survivor of 12 small strokes of the brain which occured a year ago and two heart attacks September of 2016. I have a strange reocuring cramping of my feet and up my leg whenever I am laying down in bed and i turn over and stetch my toes and I catch a cramp that moves my toes on their own with rated 12 pain. What can I do besides trying to walk it out this pain latsts a few minutes before i can even move out of bed. And sometimes the pain even elevtes up my leg to my brain and I thank the Lord for grabbing ahold of me then with prayer it gets me thru and i m able to pass with a few minutes of releif ,but i still am in a managible cramp and i m able to put some ice on it an get some comfor t and sleep a little while what do I have to do to try and avoid or cope? I open to any and all suggestions YYYY@YYYY