A combination of things will help. Magnesium phospate and calcium mostly. So yep, a banana. Or a banana smoothy with milk/yoghurt would be good.
Magnesium is a muscle relaxant so whenever you've got muscle cramps/twitches, it's likely that taking some extra mag phos with calcium will be of benefit
"Making the decision to have a child - it's momentous. It is to decide forever to have your heart go walking around outside your body." -Elizabeth Stone