George Stimpson

The rate of heartbeat varies with the age, sex and mental and physical condition of the individual. It may be said in a general way that the heart of the normal man beats about 72 times a minute, 104,000 times a day, 38,000,000 times a year and 3,000,000,000 times in a lifetime. The extreme range of the human heartbeat is from 16 to 200. An electrocardiograph film showed that the heart of a man executed by a firing squad in Utah in 1989 increased its beat from 72 to 180 a minute during the few minutes before the shots were fired. The heart of a woman normally beats on the average about eight times a minute faster than a man's does, and that of a newborn baby about [page 9] twice as fast as that of an adult. Even in the womb the heart of a female child beats faster than that of a male child, a fact that sometimes es physicians to determine whether an unborn child is a boy or girl. This faster heartbeat of females occurs also in animals. The normal pulse of a bull is 46 a minute while that of a cow is 56. The heartbeat of birds is much faster than that of mammals and is so rapid that one cannot readily count it. Three gallons of blood a minute is sent from the right to the left side of the heart and about 4,320 gallons is pumped by the heart a day. The work done by the heart in 24 hours is equivalent to the force required to raise a ton to the height of 82 feet. The heart is always in motion, never resting in the generally accepted sense of the term. But muscles "work" only when they are contracting and it requires eight times as long for the heart to fill with blood when relaxed as it does to contract and force out the blood. Therefore it may be said that the heart works one-eight of the time and rests the other seven-eights. Oddly enough, more cases of coronary occlusion—stoppage of blood flow to the heart—occur while the victims are asleep or at rest than when they are awake and active. Many deaths attributed to heart trouble are really caused by infectious diseases.