Cramps are especially common in the muscles of the foot, fingers, and calves. Physiologically, a cramp is an abrupt contraction and spasm of muscles caused by circulatory disorders or physical exertion.
A frequent cause of a cramp may be an abortive movement or monotonous repetitive motion. Such cramps develop in people typing a lot on a PC or playing with a computer mouse, working on their feet, or exercising intensively.
Leg cramps are frequently caused by a lack of calcium and potassium salts in the body. This often occurs with intense exercise, taking diuretics, and dehydration.