Worried About Clots? Take a Hike

Whether you're stuck on an airplane or glued to a computer, staying put for hours can be risky.

Dangerous blood clots in the legs--what doctors call deep vein thrombosis--made headlines after striking airline passengers on long trips. But anyone who stays inactive for hours can face similar risks for blood clots.

"Even though the condition has been nicknamed 'coach class cramping,' the problem is mainly caused by being immobile for long periods of time, not by the amount of space allocated for each passenger," says David M. Capuzzi, M.D., Ph.D., a cardiologist in Wynnewood, Pa.

"Under normal circumstances, many of these passengers might not otherwise form blood clots," says Dr. Capuzzi. But cramped inactivity may invite clotting, "especially in those passengers who may be at high risk--even during trips as short as three to four hours."

Most cause no problems

Many clots cause no symptoms and vanish when the flier lands and moves on. But some clots break loose, lodge in lung arteries, and cause serious complications.

The blood flow through veins can slow for anyone who sits or stands for long periods with no movement, says Theodore R. Sullivan, M.D., a vascular surgeon in Abington, Pa. Driving instead of flying won't help. "It's especially important to stop, get out of the car and walk around about every two to three hours during a long trip," he says.

Dr. Capuzzi says your risk of clots may rise with a history of stroke, heart disease, cancer, smoking, high blood pressure, diabetes, diseased veins, faulty valves, or abnormal blood clotting in you or your blood relatives. Pregnancy and diuretics also raise risks.

"Get up and walk around," suggests Dr. Capuzzi. If you can't leave your seat, try heel raises, toe lifts, or flexing your feet--any kind of movement can help.

"If support stockings are prescribed for you, don't forget to wear them on a long trip. Otherwise don't wear clothes that are constrictive," says Dr. Capuzzi. "And, if you take prescribed blood thinners, continue to take them."

Watch for these signs

Call a doctor immediately if you have these symptoms:

• Swelling, pain, or both, often in one leg

• A dull ache, heaviness, and pressure in the lower legs

• Tight muscles, especially in the ankles and calves