Reference: AEROBICS 2019 Update: Best Practice Recommendations (see Page 20)

HRR (heart rate reserve) = HRmax (maximum heart rate) – HRest (resting heart rate)

HRmax predict:

• Without beta-blocker medication = 206.9 – (0.67 x age)
  
• With beta-blocker medication = 164 – (0.7 x age)
  

Target HR = HRest + (X% of HRR)