Human Body

Blood and Circulation

How hard does the heart work?

The heart squeezes out about 2 ounces (71 grams) of blood at every beat and daily pumps at least 2,500 gallons (9,450 liters) of blood. On the average, the adult heart beats 70 to 75 times a minute. The rate of the heartbeat is determined in part by the size of the organism. Generally, the smaller the size, the faster the heartbeat. Thus women’s hearts beat six to eight beats per minute faster than men’s hearts do. At birth the heart of a baby can beat as fast as 130 times per minute.


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