Your heart beats about 100,000 times every day and pumps 7,570 liters (2,000 gallons) of blood.

The heart is a muscle with four sections called chambers. The top chambers are the atria and the bottom ones are the ventricles. Every heartbeat has two steps. First, the atria squeeze blood down into the ventricles. Then, the ventricles squeeze to push blood to the lungs and the rest of the body.An electrical signal starts each beat in a spot called the sinoatrial node. This signal travels through the heart to make the muscles contract in the right order. A resting heart usually beats 60 to 100 times per minute. When you exercise, it beats faster to give your muscles more oxygen.The heart pumps blood through a massive network of tubes called blood vessels. In an adult, these vessels are about 100,000 kilometers (60,000 miles) long. This is long enough to wrap around the Earth two times. The heart creates enough pressure to spray blood up to 9 meters (30 feet) away.The heart weighs only about 300 grams (11 ounces) but does more work than any other muscle. It is very good at taking oxygen from blood to keep itself running. Other muscles use about 25% of the oxygen they receive. The heart uses up to 80% of the oxygen it gets because it never stops working.