Deep vein thrombosis (DVT) is a condition in which blood clots occur in a deep vein in your body (usually the legs). If that clot travels to the lungs, it can cause a deadly pulmonary embolism.

Travel is one of the major factors that can contribute to DVTs, because sitting still for hours — whether in a car, train, or plane — can cause the blood to pool in your legs, and lead to the formation of clots.

When you travel by car, it is imperative to take advantage of every rest stop you come across to get out and stretch your legs. And if you’re on a train or plane, you need to get up and walk around frequently.

This sounds simple, but it’s your best protection.

If you’ve experienced any type of blood clot in the past, talk to your doctor about special precautions to take, such as wearing compression stockings.

In addition, taking aspirin during your trip can help prevent blood clots. Discuss that option with your physician before you set out.