The blood that travels through the arterial system has the advantage of the heart muscle to provide force, but the venus system must use another process to move against gravity back to the heart. This system is the venus pump system. Using a system of one way valves and muscle contraction, the blood moves slowly against gravity to the heart. If a person stands or sits for long periods of time without any muscle contraction, these valves can be damaged from pooling of the blood. This leakage causes the blood to pool near the surface and triggers the development of varicose veins and spider veins.
Experts say that spider veins occur mostly on the legs and face and are also known as telangiectasia. They begin in a woman’s 40s and 50s and are formed when superficial veins near the skin surface leak tiny amounts of blood.