In the train ride or standing position after a day of work will appear calf and foot swelling, often not accompanied by pain at the same time, this situation belongs to the normal phenomenon. The main reason is that the standing time is too long, the body’s blood due to the influence of gravity, to the lower limbs flow more, while the venous valve insufficiency or muscle does not move, do not contract, no squeeze on the blood vessels, not able to promote venous return. As a result, the accumulation of blood in the lower limbs increases compared to normal, producing extravasation of tissue fluid and swelling of the feet or lower legs.