The veins transport the blood back to the heart. Valve valves in the veins prevent the blood from flowing back in the wrong direction. In addition, the "muscle pump" supports the return of the blood: As with a water hose that is squeezed, the muscles compress the leg veins with each movement and thus the blood continues.
Facts and figures about veins
But about every second German is no longer healthy legs. The upright walk man has the other mammals ahead, but he also brings him disadvantages. Thus, the blood circulation is demanded maximum performance, because the blood has to return from the toes to the heart: through the veins and against gravity flow 9, 000 liters daily. That's equivalent to over 500 boxes of mineral water that you wanted to raise to the table.
The blood flow through the veins
The blood does not flow back from the body to the heart just because the heart is pumping. The blood in the veins is also transported to the heart, because the vein walls contract together with their muscles.
So that the blood does not come off the way, the veins have valve-like locks, also called venous valves. These check valves open only at a pressure from below and quit at a return flow from above immediately. The venous muscle pumps on the sole of the foot, the ankle and the calf are also involved in the return of the blood to the heart. As you run, your muscles will repeatedly press on your veins, helping to push the blood toward your heart.
Well conceivable, therefore, that some burdens are poison for the veins, such as the constant standing in many occupations. By gravity, the blood pushes down and thus constantly against the valves and walls in the deep veins of the legs. The venous walls are no longer able to cope with the strain after some time and give way. Due to the enlargement, the venous valves do not close properly and only a part of the blood is transported back. Another part is pushed into superficial veins, which also expand.
It comes to varicose veins. There, the blood flow is slowed down, the blood builds up and water is forced out of the bloodstream into the surrounding tissue (edema). Especially in the evening, the legs are heavy and swollen, pain, tingling or itching. Over time, the venous walls also take damage. They lose their elasticity and become susceptible to inflammation and blood clots (thrombosis).
Causes of weak veins
The development of venous disorders is particularly favored by the following risk factors:
- sedentary lifestyle
- Predominantly standing or predominantly sedentary activity (legs motionless in the vertical)
- Taking birth control pills, especially in smokers and women over 30 years
- Blood congestion through surgery
- increased coagulation tendency
- hereditary venous and connective tissue weakness