Final answer:
The Age-predicted method is easier to calculate and may be used in group settings or maximum effort exercises, but it is not as accurate due to the simplistic linear formula it relies on.
Step-by-step explanation:
The method that is not as accurate as HRR, easier to calculate, and may be used in group personal training or exercises where you would push to max HR is the Age-predicted method (d). Maximum heart rates (HRs) decrease with age, and can be roughly estimated by subtracting the individual's age from 220 bpm. So, for example, a 40-year-old would have a maximum HR of around 180 bpm, and a 60-year-old would have a maximum HR of about 160 bpm. However, this method accounts for only 1.5 percent of the HR variation, showing that the relationship between age and maximum HR is not simply linear.