My foot is spasming, why?

It keeps on twitching and cramping up. And i don't know if it's from going on the treadmill or a vitamin deficity. Any ideas what's causing it?My foot is spasming, why?
Any muscular spasming or charlie horses could be sign of a potassium deficiency. But you cannot take much potassium, or try to self-regulate it with megavitamin as you might C or B12, say. Eat a couple of bananas and a couple of glasses of orange juice a day to try to correct it.
(NOTE: Most potassium vitamins from the pharmacy have a fraction of your daily value... again, it is easy to get a dangerous level of potassium, which can directly effect the heart.)
Take some calcium/magnesium tablets for a week. Cut down on tea, coffee and alcohol. Drink plenty of water.
You will be all right.