Heart Rate
In a normal, healthy individual the typical resting heart rate is between 60-80 beats per minute (BPM). It is not uncommon, however, to see significant fluctuations in these normal values with relatively healthy individuals. For example, sedentary individuals may have a resting heart rate of over 100 BPM while some conditioned athletes may have rates as low as 28-40 BPM. The vast discrepancies between the high and low values primarily reflect the efficiency of the heart. The heart of a trained individual has adapted to become capable of ejecting more blood with each beat. When one begins to exercise, the nervous and endocrine system respond by influencing the heart’s beating frequency and force. In response to exercise, heart rate will rise in a predictable manner. The speed of the heart rate will increase in proportion to the increasing workload. The workload may be measured in total oxygen uptake, as it is directly related to the workload. Total oxygen uptake is measured in liters per minute. It is a direct measurement of how much oxygen is being extracted by the tissues, which is used for energy production to perform work. As noted earlier, there is a proportional increase in heart rate as workload increases.
Statistically speaking, the maximum heart rate is predictable based on a person’s age. Max heart rate decreases about one beat per year starting at roughly 10-15 years of age. To estimate maximum heart rate one would take the number 220 and subtract it from the person’s age. Note that this is an average and heart rate may fluctuate +/-12 BPM per individual.
Maximum Heart Rate Estimate: 220 – age