Hi, everyone. Was struggling with the cramps a while back.
Increased my exercises, and that's made a big improvement: walking 45 minutes 5X/week, and doing squats and deadlifts w dumbbells 2X/ week (besides upper body weight training).
Also my watch reminds me to stand up every so often while I watch TV or read, do puzzles, play bass, etc.
Hope this helps... please adjust your exercise to your own physical status and current level of fitness / health. And if any exercise hurts as you do it, stop doing it... and search for another one in its place that doesn't.
All the best!

/LarryG