What is a cardiovascular system



All human blood flows through within 60 seconds
- that's 5 to 6 liters - once the organism.

The heart

The heart, a hollow muscle, lies immediately behind the breastbone, the apex of the heart points to the bottom left. The heart consists of a left and a right half. Each of the two halves of the heart, separated by a septum, has a smaller atrium and a larger chamber. Between the atrium and the chamber and at the exit of the chambers there is a heart valve to control the blood flow. When doing light activity, an adult's heart beats about 60 to 80 times per minute.

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The great circulatory system
The oxygen-enriched blood in the lungs reaches the left atrium and from there into the left ventricle. The contraction of the heart chamber (systole) pumps the blood through the aorta into the arteries and transports it into the body. The capillary releases oxygen and nutrients and absorbs carbon dioxide and waste products. Then the deoxygenated blood is transported back to the heart in the veins. When the blood enters the right ventricle via the right atrium, the great circulatory system ends.

The small pulmonary circulation
The right atrium picks up the oxygen-poor blood from the body and routes it to the right ventricle. It pumps this through the pulmonary artery into the lungs. This is where the uptake of oxygen and the release of carbon dioxide take place. The oxygen-enriched blood reaches the left atrium and the left ventricle via the pulmonary vein. Here the pulmonary circulation ends and the body circulation begins.

Blood and blood pressure
The blood vessels (arteries, veins) form a closed transport system. The means of transport is blood. It takes over the supply of the body with nutrients as well as its disposal of metabolic products. In order to maintain the blood circulation, a certain pressure - the blood pressure - must be present. When the heart contracts, the pressure increases. This pressure increase is called systolic blood pressure, it is the first higher value mentioned when measuring blood pressure. When the heart slacks, the pressure drops. The pressure during the relaxation phase is called diastolic blood pressure, it is mentioned in the second place when measuring blood pressure and corresponds to the lower value.

Sports heart
A sports heart is the enlarged, also hypertrophied, healthy heart of the trained endurance athlete. It is characterized by increased capillarization, througha strengthened heart muscle, through the increase in the heartbeat volume at rest and during exertion (lowering of the resting and exertion pulse), through a reduction in the oxygen requirement of the heart muscle at rest, through a higher exercise capacity and through less exertion at a given stress level. The sports heart offers increased performance requirements for endurance loads.