Night cramps (often called nocturnal leg cramps) are sudden, painful muscle contractions that usually affect the calf, foot, or thigh while you’re sleeping. The exact cause isn’t always clear, but common reasons include:
- Muscle fatigue or overuse from exercise or standing for long periods.
- Prolonged sitting or sleeping in a position that keeps the foot pointed downward, shortening the calf muscle.
- Dehydration, which may contribute in some people.
- Low levels of certain minerals (such as magnesium, potassium, or calcium) can be a factor, though they’re not the cause in most otherwise healthy people.
- Certain medications, including some diuretics and cholesterol-lowering drugs, may increase the risk.
- Pregnancy, especially in the second and third trimesters.
- Underlying medical conditions, such as diabetes, nerve disorders, kidney disease, or poor circulation.
To help prevent night cramps:
- Stretch your calf and hamstring muscles before bed.
- Stay well hydrated throughout the day.
- Avoid sitting or standing in one position for long periods.
- If you exercise intensely, include a cool-down and gentle stretching afterward.
- Wear supportive footwear if you’re on your feet a lot.
If you get a cramp, gently straighten the affected leg and pull your toes toward your shin. Walking around or massaging the muscle and applying warmth can also help it relax.
If your cramps are frequent, severe, affect only one leg with swelling or redness, or are accompanied by muscle weakness, it’s a good idea to see a healthcare professional to look for an underlying cause.
