You need 1200-1500mg of Calcium and 400-600 mg of magnesium a day to help with the cramps. Your products say 1000mg cal / 500mg magnesium - if that is for one pill then I would not recommend taking 4 of them, If that is what 4 pills give you then I would say take 2 in the morning, one with lunch and one a hour before bed. The one before bed will help with the 'night cramps' that happen.

Nat