The heart rate is one of the cardiovascular measurements employed during exercise to measure the strength of the heart relative to the exercise and the rate of recovery from the exercise. This is important in terms of specifying exercise intensities for different individuals. The maximal heart rate entails the maximum increase in cardiac output, which cannot be surpassed relative to an increase in the intensity of the exercise. According to Robergs and Landwehr (2), the maximal heart rate can be predicted using the equation, HRmax = 220-age.
This equation was developed in 1938 by Robinson and it is the most accepted formula in the prediction of the maximum heart rate. When starting any physical activity, there is a direct proportional increase in the heart rate with the level of intensity of the physical activity in question. This condition proceeds until the maximum intensity is reached. At this point, the heart rate begins to flatten gradually despite that the exercise continues and the intensity increases. This indicates that the highest point of the heart rate is approaching and this value remains constant until an individual gets exhausted. Moreover, an individual’s maximal heart rate remains constant each day (Robergs and Landwehr 3).
However, Robinson noted that the maximal heart rate can decrease annually relative to an increase in age as from 10-15 years. Therefore, the maximal heart rate depends on an individual’s age. Consequently, when the age of a person is subtracted from 220, we are then able to approximate the heart rate of such an individual.
However, a large error of prediction (Sxy=7-11 beats per minute) is involved in using the equation, HRmax=220-age. Besides, Robergs and Landwehr (4), reveal that the equation, HRmax=220-age was not developed using primary data and that the data used in developing the prediction equation was obtained from more than 11 published and unpublished studies (Robergs and Landwehr 6).
Due to the inherent errors in the equation, HRmax=220-age, other equations that predict the maximal heart rate relative to age were developed. A review of these equations also notes that there is a large inherent error of prediction when using these equations to predict the maximal heart rate. These errors are attributable to lack of a mode-specific method of HRmax prediction relative to age because most regression equations are mode-specific (Robergs and Landwehr 7). Besides, mode-specificity as one of the variables in the prediction of HRmax has not been accurately incorporated into most of the equations used to determine the maximal heart rate.
Therefore, because of the presence of other factors such as different exercise procedures and the motivating factors affecting different people during the exercise, there is the need to allow for prediction errors in the equations used to predict the heart rate. Here, the prediction error for accurate measurements of HRmax is equal to ±3 beats per minute (Robergs and Landwehr 7). And since HRmax is the basis of other cardiovascular measurements such as estimation of the exercise intensities and the volume of oxygen consumption during exercise (VO2max), there is a paramount need to consider the error of prediction involved in estimating the maximal heart rate.
On the other hand, the best equation for estimation of the heart beat is HRmax=208-(0.7 × age). According to this equation, when an individual is exercising at a constant rate and sub-maximal intensity, the heart rate increases steadily until it reaches a maximum, which is also the optimum heart rate. Subsequently, any further increments in the intensity will give rise to a new optimum heart rate that meets the demands of the circulatory system. This equation can be used on different populations of people under different circumstances.
Works cited
Robergs, Robert and Landwehr, Roberto. “The surprising history of the “HRmax=220 age” equation.” Journal of Exercise Physiology Online 5.2 (2002): 1-10.