Implementing several simple measures can dramatically reduce the development of a clot in the deep veins of the leg which can result from sustained immobility during travel. All the measures are designed to counter three conditions that predispose an individual to blood clot formation:

	Reduced blood flow (stasis)
	Damage to the walls of the deep veins in the leg, which may result from vein dilation (stretching of the vein wall)
	Blood hypercoagulability (an increase in the tendency of blood to clot)

Reginald S.A. Lord (St. Vincent’s Hospital, Darlinghurst, Australia) recommends that all travelers over 40 should wear elastic support stockings, abstain from alcohol consumption, move around the cabin freely, drink plenty of non-alcoholic beverages and try to avoid hip and knee angulations for prolonged periods.9 Many doctors who have published on the topic have recommended the following precautionary steps to overcome these factors based on the travelers level of risk:^{3,4,5,6,8,13,14,15,16}

Low Risk Travelers
(Everyone on travel in sitting position greater than 5 hours)

Moderate Risk Travelers
(Over the age of 40, severe varicose veins, heart failure, chronic venous insufficiency, hormone therapy, obesity, pregnancy/postpartum)