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Although high-powered executives may deny it, sleep is actually a highly productive part of life. It may not show up on the corporate balance sheet, but it's essential to rest the mind, so it can be efficient and creative during the day. And sleep is just as important for the body. It gives muscles and joints time to recover from an active day and regroup for another go at the world.

But for at least 12 million Americans, it doesn't work that way. When they settle down for a good night's sleep, they have an irresistible urge to move their legs. The result is a miserable night of fragmented sleep, daytime sleepiness, personality changes and often a grumpy spouse. The problem is restless legs syndrome (RLS).

What RLS Feels Like

Leg discomfort is the first symptom of RLS. People usually describe the feeling as tingling, pricking, bubbling, tearing or burning. People say it's like "ants crawling up my legs" or "soda pop in my veins."

Most often, the discomfort is felt deep inside the calves, but it can also occur in the thighs or feet. In most cases, both legs are equally affected. A few patients report temporary relief from massaging their legs. In severe RLS, symptoms can also develop in the arms.

Most types of leg pain are triggered by activity and relieved by rest, but in RLS, it's the reverse. The symptoms begin during rest and are most intense when the sufferer is — or should be — the most comfortable. RLS typically begins in bed at night, but it can also develop when people settle into a chair.

The symptoms usually begin shortly after bedtime. As RLS becomes more severe, the discomfort begins earlier and earlier in the day, but always gets worse at bedtime.

The only way people with RLS can stop the ants crawling through their legs is to move about. They fidget, adjust their legs, and toss and turn in bed. The urge to move is irresistible. In severe RLS, patients have to get out of bed and pace the floor to get relief.

The result is a truly bad night's sleep that causes:

  • Morning headaches

  • Fatigue or exhaustion

  • Afternoon sleepiness

  • Poor concentration

  • Impaired memory and productivity

  • Personality changes that range from grumpiness to depression and even bizarre or inappropriate behavior

Double Trouble

About 80% of people with RLS also have a related disorder,periodic limb movement disorder (PLMD). The legs jerk spasmodically ("Elvis legs") every 30 seconds or so during the nondreaming phases of sleep. Unlike the creepy discomfort of RLS, the jerking movements of PLMD occur during sleep, so the patient doesn't know they are occurring — but his bed partner certainly does. And even if jerking legs don't wake a person up, they impair the quality of sleep (and, perhaps, the marriage).

Who Gets RLS — and Why?

RLS is very common. About 10% of all adults have it. Fortunately, only about a quarter of all people with RLS are affected seriously enough to require medical attention. RLS becomes more common as people get older, but it can begin surprisingly early in life. In early childhood RLS is often misdiagnosed as "growing pains" or attention deficit disorder. RLS is more common in females than males.

In most cases, the cause is unknown. About 50% of patients have a strong family history of RLS, and researchers have linked the disorder to specific genetic abnormalities. A genetic basis is particularly likely in patients whose symptoms begin before age 45 (early-onset RLS). RLS has also been linked to other medical problems. Iron deficiency is the most common, which is why RLS often develops in regular blood donors. It has also been linked to diabetes, kidney disease, varicose veins, rheumatoid arthritis and Parkinson's disease, among other problems. When an underlying disease is linked to this syndrome, it's called secondary RLS. But in most cases RLS strikes without rhyme or reason; then doctors call it primary RLS.

Reference: Sleep Disorders section on Better Medicine

More Information on Restless Legs Syndrome

Did You Know?

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A combination of moderate aerobic exercise and lower-body resistance training 3 times per week may reduce symptom severity by about 50%.