What is my heart rate reserve or working heart rate? What is the Karvonen formula?
Your heart rate reserve is the gap between your resting heart rate and your maximum heart rate. For example, my maximum heart rate is 190bpm (four beats a minute higher than the rule of thumb based on my age predicts); and my resting heart rate is 48bpm. This means my heart rate reserve is: HRR = 190 – 48 = 142 bpm. To get the heart rate corresponding to the aerobic threshold, which is at 85% of my heart rate reserve, I have to add 85% of my heart rate reserve rate to my resting heart rate. So the heart rate corresponding to my aerobic threshold is estimated to be: AT = 48 + (0.85 x 142) = 169. This way of calculating a heart rate zone is known as the Karvonen formula.
