(HealthDay News) -- A muscle cramp is a painful contraction that may make the muscle feel hard or bulging.
The U.S. National Library of Medicine offers this list of common triggers:
- Drinking too much alcohol.
- Not drinking enough water.
- Exercising heavily or having muscles that are fatigued from overuse.
- Having hypothyroidism, a thyroid gland that doesn't produce enough of a certain hormone.
- Having kidney failure.
- Taking certain medications.
- Being pregnant.
- Consuming insufficient amounts of calcium or magnesium.
