Muscle cramps are most common in people over age 65, affecting more than two-thirds of that age-group.

CNN: What causes muscle cramps?

Cramps (tightening of a muscle) happen most frequently in calf or thigh muscles but may affect other muscles such as those in the hands, feet, abdomen or rib cage.

CNN: What causes muscle cramps?

Your doctor may suggest a stretching program, certain exercises, over-the-counter or prescription pain relievers or muscle relaxants for severe or repeated cramps.

CNN: What causes muscle cramps?