Night cramps are “sudden, involuntary spasms that cause sharp pain.” They often affect the calves or feet and can last from a few seconds to several minutes, sometimes disrupting sleep.

One of the most common causes is dehydration. When the body lacks fluids, electrolyte balance is affected, making muscles more likely to cramp. Low levels of minerals like magnesium, potassium, or calcium can also increase the risk.

Physical habits matter too. Overexertion during exercise can strain muscles, while a sedentary lifestyle can lead to stiffness. Long periods of sitting, standing, or poor posture may also put stress on leg muscles, making cramps more likely at night.

Other triggers include nerve compression, pregnancy-related changes, certain medications, and alcohol use. Some health conditions—such as diabetes, thyroid issues, kidney disease, or circulation problems—can also contribute by affecting nerves or blood flow.

Relief usually focuses on simple actions. Stretching, massaging the muscle, or applying heat can ease the pain quickly. Walking or adjusting foot position may help stop the cramp. Preventing future episodes involves staying hydrated, maintaining proper nutrition, and keeping muscles active and flexible.