Hearth rate reserve (hrr)

Hearth rate reserve (HRR) is the difference between resting heart rate (HRrest) and maximum heart rate (HRmax).
Exercise HR = % of target intensity (HRmax – HRrest) + HRrest

For example: Target intensity 70 % HRR for a person with HRmax 201 bpm and HRrest 50 bpm

Exercise HR= 70% (201-50=151) + 50
Exercise HR=155 bpm