At some point, the concept of the second heart of the human body began to circulate. The speed of knowledge dissemination in the information age is accelerated, and the process is inevitably distorted, intentionally or unintentionally, such as far-fetched in some mysterious healing theory. To understand the root, we have to start with the blood circulation of the human body.
The circulatory system is one of the cores of the functioning of life
Blood circulates throughout the body and triggers various chemical reactions. Once it stops, each organ is severely damaged within a short time and can never recover (5-6 min for brain tissue; 10-20 min for liver and kidney). And there are two components that maintain the functioning of this system: the heart and blood vessels.
1, the heart provides the power for the continuous flow of blood in the blood vessels, working continuously from the mother’s womb to leaving this world, we see it as a pumping organ composed of heart muscle tissue, referred to as the heart pump.
2, blood vessels are distinguished into arteries, veins and capillaries. Among them, the veins are the body’s blood storage reservoir, collecting blood flow back to the heart. The amount of blood stored in the veins can be up to 60-70% of the total blood volume.
The pathway of blood flow is heart – arteries – capillaries – veins – heart.
It is obvious that the heart alone is not enough to power such a large amount of blood flow back to the heart in the veins.
In addition to the heart itself, other forces that promote the return of blood to the heart.
1, change of body position: veins are most affected by gravity, when standing, the lower extremity venous blood storage volume increases, compared with lying down to increase 500 ml of blood. The amount of blood returned to the heart is the largest when practicing inversion, and the most test of the heart’s ability; so whether standing or sitting, the amount of blood returned to the heart is reduced when the limb is sagging. Patients with heart failure, doctors will be thousands of instructions to legs down, because the reduction in blood volume represents a reduction in the burden on the heart.
2, respiratory movement: respiratory movement has an autonomous rhythm, but also can be partially subjective control by the person. In the process of inspiration, the thoracic volume increases, the negative pressure increases, the need to absorb part of the venous blood to occupy the space, so it also indirectly becomes a booster of venous blood back to the heart.
3, the skeletal muscle squeezing role: human movement can not be separated from the skeletal muscle. In the contraction of the whole body muscles, experience the joy of movement, the veins between the muscles are squeezed, the blood will naturally accelerate the flow in the direction of the heart, accelerate blood circulation, and then promote the body’s metabolism. So remember, life is exercise, brisk walking is a good way to exercise.
It is worth noting that whether it is the heart or breathing movement is a certain autonomous rhythm, without the brain to deliberately control. Skeletal muscles are different, most of them receive instructions from our brain, so the veins want to achieve the purpose of transporting blood back to the heart, the movement of the whole body muscles is controllable and the easiest to achieve, that is to say, the initiative is in our own hands.
The initiative of skeletal muscle movement is in our hands!
There are 600-700 skeletal muscles that the human body can control, and of such a large number of muscles, the greatest influence on blood circulation comes from the lower legs.
Other mammals do not have calves as developed as humans, even the most similar to humans, the orangutan. As humans evolved from crawling on four feet to standing on two, with their hands free to create modern civilization, the calves bravely took more pressure and therefore provided more power.
Within the veins of the calf area, approximately every 5 cm, there exists a valve that prevents blood from flowing backwards, and the blood vessels and muscles together form a device that allows the venous blood flow to return to the heart in an orderly manner and avoid reflux, the essence of its role is similar to that of a heart pump, medically called a muscle pump or venous pump.
As an example.
If you stand still immediately after reaching the finish line of a long-distance running race, you lose the role of the muscle pump, and a large amount of venous blood immediately stays in the lower extremities and abdominal cavity, and the amount of blood returned to the heart decreases, so the heart can’t cook without rice, and the amount of blood pumped out decreases, and the blood supply to the brain decreases, causing temporary cerebral ischemia, and vertigo or even fainting occurs.
Therefore, from the perspective of blood circulation, the second heart of the human body is the calf!