If you spend a lot of time on airplanes – especially long-distance flights – that recurring pain in your legs may be a warning that you're at risk of developing deep vein thrombosis (DVT) and becoming a medical statistic. At the time of publication, experts say that DVT annually affects approximately 80 people out of 100,000.

This potentially life-threatening condition is triggered by the formation of blood clots, typically within the thighs and calves, often causing pain in leg muscles. Leg pain that is concentrated in one leg or that lingers long after the flight is over, chest pain, or shortness of breath are indicators to see a health care provider.

Risk Factors

Although long periods of immobility are frequently associated with the development of DVT, other factors significantly escalate the risk. These include a family history of blood clots, blood circulation issues, or clotting disorders, taking estrogen birth control pills, hormone replacement therapy, obesity, varicose veins, smoking, recent surgeries and pregnancy. As you get older you also have an increased risk of DVT or thromboembolism.

Symptoms

The long periods of time and inactivity while sitting on a plane during air travel can cause your feet, ankles and legs to swell. This swelling occurs as a result of blood pooling in your lower extremities, which puts more pressure on the leg veins. Aching, muscle tightness and tenderness in the lower legs and thighs are typically the first symptoms of pain someone may experience. The skin surface may also feel warm or swollen when touched, coupled with areas of redness. In addition, you may experience a slight fever.

Prevention

A critical component of healthy flying, especially on long flights, is to move about the cabin when it is safe to do so. Simple exercises include walking back and forth, doing foot and knee lifts, and performing ankle flexes and rotations. Be sure to wear loose-fitting clothing that will comfortably allow movement and blood flow. If possible at the time of check-in, upgrade to a seat with extra leg room, an aisle seat, or to request an exit row, this seat will offer more space to stretch your limbs.

Limit the consumption of caffeine and alcohol, but stay hydrated by drinking plenty of water. Try not to fall asleep for more than a half-hour to avoid those cramping calf muscles. If the flight has a layover, don't head for the nearest place to sit down again; instead, engage in a brisk power walk through the terminal.

Treatment

The objective of medical treatment is to reduce the size of the clot before it can travel to or obstruct the blood vessels. You can take anticoagulant medications to thin your blood, or wear compression stockings that are designed to squeeze your ankles and calves and force the blood in your lower leg veins back toward the heart; this hosiery can also be worn in-flight as a preventative measure. In addition to physiotherapy treatments to improve circulation, there is a surgical procedure involving the insertion of a filter to trap blood clots and prevent them from entering the lungs.