The low and high target heart rate zones for the 46-year-old teacher with a resting heart rate of 78bpm are;
Low target heart rate = 87 bpm
High target heart rate = 131 bpm
We are told that the resting heart rate of the 46 year old teacher is 78 bpm.
Now, the formula for calculation of the estimated maximum age-related heart rate is;
Maximum age related heart rate = 220 – person's age
For this 46 year old man;
Maximum age related heart rate = 220 - 46
Maximum age related heart rate = 174 bpm
Now. since his resting heart rate is average at 78 bpm, then the low and high target heart rate will be gotten from the formula;
Low target heart rate = 50% × Maximum age related heart rate
High target heart rate = 75% × Maximum age related heart rate
Thus;
Low target heart rate = 50% × 174
Low target heart rate = 87 bpm
High target heart rate = 75% × 174
High target heart rate ≈ 131 bpm
Read more about target heart rate at; https://brainly.com/question/770092
