Harvard Women's Health Watch

In the journals: Exercise eases nighttime leg twitches

In the journals

Exercise eases nighttime leg twitches

Stress and worry — and sometimes a partner's snoring — can keep us up at night, but some women may be losing sleep for a less obvious reason. Periodic limb movement disorder (PLMD) may cause their legs to kick or jerk every 20 to 40 seconds for minutes to hours during sleep. Even when they are not awakened by these episodes, they may suffer from problems related to chronic sleep loss, including daytime drowsiness and lack of alertness, because normal sleep patterns are disrupted.

PLMD can be treated with medications, but a study indicates that exercise may also be effective. Brazilian researchers found that single sessions of intense exercise as well as longer-term regular workouts reduced leg muscle contractions and improved sleep in a small group of people with PLMD (Medicine & Science in Sports & Exercise, January 2009).

PLMD is less familiar than a related sleep-disrupting condition, restless leg syndrome (RLS). RLS affects about 10% of people ages 30 to 79, two-thirds of them women. Most people with RLS also have PLMD, but the reverse is not true. According to some estimates, as many as 30% to 50% of people ages 65 and over have PLMD. However, that figure is based on observation of leg twitches alone, and people whose legs twitch don't necessarily experience the brief, unconscious awakenings that disrupt sleep. Like RLS, PLMD can have various medical causes, including iron deficiency and diabetes. Some experts think abnormalities in nerve regulation are involved.

To continue reading this article, you must login.
  • Research health conditions
  • Check your symptoms
  • Prepare for a doctor's visit or test
  • Find the best treatments and procedures for you
  • Explore options for better nutrition and exercise
Learn more about the many benefits and features of joining Harvard Health Online »