How It Works
male and female joggers stretching and resting before a run

What is cramp?

male and female joggers stretching and resting before a run

A cramp is an involuntary contraction or shortening of muscle, and it’s often painful.

There are two main kinds of cramps: skeletal muscle and smooth muscle cramps. The former include leg spasms, which you might call a dead leg, charley horse or corker. Smooth muscle cramps, meanwhile, include menstrual or stomach cramps.

Skeletal muscle cramps have many different causes. You can bring them on by straining or overworking a muscle, or failing to stay hydrated when exercising, especially in hot weather. Health conditions like atherosclerosis (hardening arteries) in your legs can be the culprit because the muscles aren’t getting enough blood, plus deficiencies in some vitamins and minerals – like potassium – can also trigger this kind of cramp.

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