Heart Rate

Heart rate is considered one of the four vital signs. Usually it is calculated as the number of contractions (heart beats) of the heart in one minute and expressed as "beats per minute" (bpm). See "Heart" for information on embryofetal heart rates. When resting, the average adult human heart beats at about 70 bpm (males) and 75 bpm (females); however, this rate varies among people and can be significantly lower in endurance athletes. The infant/neonatal rate of heartbeat is around 130-150 bpm, the toddler's about 100–130 bpm, the older child's about 90–110 bpm, and the adult's about 80–100 bpm. 75 beats per minute translates to 4500 beats an hour, 108,000 beats per day, or about 39,420,000 beats in a year. The pulse is the most commonly used method of measuring the heart rate. This method may be inaccurate in cases of low cardiac output, as happens in some arrhythmias, where the heart rate may be considerably higher than the pulse rate. Listening to heart beats using a stethoscope, a process known as auscultation, is a more accurate method of measuring the heart rate.