I've noticed that mine get worse if I don't drink enough water during the day. I usually have to wake my DH to rub my leg until the cramp goes away, which is a bad thing when he is on nightshift lol.

Also if I do a lot of leg crossing/squating/bending down during the day, I usually end up with the killer cramps that night as well.

I've been trying to have a nice shower before bed with the warm water running over my legs.

Nic