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The cardiovascular system is made up of the heart, veins, arteries, and capillaries. It is your body's transportation system, carrying food and oxygen to your body's cells. Your heart pumps blood through the system: oxygen-rich blood from the lungs goes out through the arteries and waste-filled blood comes back through the veins to be cleansed and recharged with oxygen. The cardiovascular system also retrieves blood from your legs and lower torso, carrying it upwards against the force of gravity. Inversion allows your body to work with gravity to ease the circulation process.