You’re sound asleep — then suddenly, a sharp, tightening pain shoots through your calf or foot.

You’re hit with a nocturnal leg cramp: an involuntary, often painful muscle contraction that strikes without warning, usually in the calf, foot, or hamstring.

These cramps can last from a few seconds to several minutes — leaving behind soreness and sleep disruption.

While nearly everyone experiences them now and then, research shows that certain groups are far more likely to suffer from night cramps — and some may even deal with them nightly.

Let’s explore who is most at risk, why they happen, and what you can do to find relief.