Here in Florida we train year round, we have heat indexes that reach into the triple digits so its important our athletes are familiar with what heat cramps are and how to prevent them.
Muscle cramps are common and may be precipitated by prolonged physical activity, high heat and humidity (black flag conditions), dehydration and/or poor conditioning. Cramps are characterized by the sudden onset of moderately severe to incapacitating pain in the muscle belly and may progress to involve other adjacent muscle groups.
The first treatment consists of immediate re hydration with a fluid containing electrolytes. After beginning re hydration, further treatment should consist of grasping and applying pressure to the muscle belly and immediately stretch the muscle until the cramp resolves. The calf muscle, for example, would be stretched by flexing the foot toward the head, whereas a thigh cramp would be treated by flexing the knee, bringing the foot to the buttocks.
I personally use Herbalife Drive C7 which replenishes the electrolytes lost when I train hard. Gatorade is good too just watch the sugar content. And the king is drink lots of water so you don't get dehydrated in the first place.