Heart Rate Reserve (HRR)
Heart Rate Reserve (HRR) is the difference between your Maximum Heart Rate (HRmax) and Resting Heart Rate (HRrest). Exercise intensity can be evaluated by calculating your heart rate as a percentage of HRR. The calculation to work out %HRR is (HRex – HRrest)/(HRmax – HRrest), where HRex is the exercise Heart Rate. So a HRmax of 180, a HRrest of 40 and HRex of 140 would be (140 – 40)/(180 – 40), which is 71%. Using %HRR is better than a percentage of HRmax, as it reflects the relative intensity more accurately. For example, if two athletes both have a HRmax of 180, but one has a HRrest of 40 and the other 70, at a HR of 140 they would both have the same %HRmax, but one is at 64 %HRR and the other is at 71 %HRR. However, for HRR to be of value, you have to test your HRmax, as it cannot be calculated. Most Heart Rate Monitors will display your %HRR if you input your HRmax and HRrest.
