Your veins are responsible for collecting blood from the circulation and returning it to your heart. If you have history of clot formation, or venous thrombosis, you may have a disease that affects the veins or blood. Exercise is a natural treatment for the prevention of thrombosis.
Vein Physiology
While arteries are capable of controlling blood flow by changing their diameter, your veins are essentially inert networks of pipes, which collect tributaries from small capillary vessels and direct blood back to the heart. Additionally, the pressure within veins is much lower than in the arteries. Both these features lead to increased stasis, or pooling of blood within veins. Physical activity acts to increase the pressure within veins, improving venous return of blood and decreasing the probability of clot formation.
Venous Thrombosis
According to "Harrison's Principles of Internal Medicine," this condition may present pain, swelling or tenderness in the leg. Venous thrombosis may occur for a variety of reasons, but there are three core factors predisposing to thrombosis: increased venous stasis, blood vessel damage and hypercoagulability -- or increased connective forces between red blood cells and platelets. These factors are often observed in patients on certain medications, with recent surgeries, and those undergoing cancer treatment. Additionally, an emergency complication of thrombosis is a pulmonary embolism, which presents with shortness of breath, chest pain while breathing, and coughing up blood.
Varicose Veins
This condition results from problems with the structure of veins; incompetent valves or weak venous walls may lead to the development of varicose veins. Symptoms include an aching, or pressure sensation in the legs after long periods of standing. Ankle swelling may occur as well as the appearance of dilated, tortuous veins on the surface of the skin. Poor venous return is the root cause of this condition; conservative treatment includes elevating legs periodically, avoiding long periods of standing, and wearing elastic band socks to increase the return of blood to the heart. Exercise is another intervention that would improve symptoms if you have varicose veins. This is because when you exercise, your muscles are contracting; this forces blood from the veins and, in this case, partially compensates for the malfunctioning venous valves.
Applications
With few flow regulatory mechanisms available, veins are highly susceptible to clotting, particularly during periods of little physical activity. According to the National Heart Lung and Blood Institute, hospital patients who have been in bed for long periods must be monitored for clotting in the legs due to increased blood pooling. Exercise can be helpful in preventing blood stasis and the manifestation of venous thrombosis.
References
- "Harrison's Principles of Internal Medicine, 17th Edition;" Joseph Loscalzo, M.D., Ph.D., et al; 2008
- National Heart Lung and Blood Institute: Deep Vein Thrombosis
