Example2.1.8Target heart rate

According to the American Heart Association, maximum heart rate in beats per minute (bpm) is given by \(220 - a\text{,}\) where \(a\) is age in years.

  1. Determine the maximum heart rate for someone who is \(31\) years old.

  2. Target heart rate for moderate exercise is \(50\%\) to \(70\%\) of maximum heart rate. If we want to reach \(65\%\) of an individual's maximum heart rate during moderate exercise, we'd use the expression \(0.65(220-a)\text{,}\) where \(a\) is their age in years. Determine the target heart rate at this \(65\%\) level for someone who is \(31\) years old.