Your training or target heart rate (THR), is your desired heart rate at any given time during exercise. The higher your target heart rate, the harder you are working. You can choose to use many methods to calculate this rate.
The first and most common method to find your training heart rate is to use the “220 minus age” formula. Start by calculating your Heart Rate Maximum (HRM) by subtracting your age from 220. Your training heart rate is then figured as a percentage of this maximum rate. Higher percentages of your maximum means you’re working harder. For example, to find 70% of your HRM, you would multiply that number by .70, and that number would be “70% of your heart rate max”. This is a quick and easy way to figure out your target heart rate but it is not the most reliable because it does not take into account your individual fitness level. To get a more individual reading that attempts to consider your fitness level, you can use formulas like the “Karvonen Formula”. This system takes into account your resting heart rate which can be a predictor of fitness. This formula is:
THR (target heart rate) = ((HRM – resting HR) x %Intensity) + resting HR
To find your HRM in the formula, you would subtract your age from 220. To get your resting heart rate, take your pulse before you get out of bed in the morning for one minute. For best results, do this 3 mornings in a row and use the average.
Example: subject is 40 years of age and has a resting heart rate of 70 beats per minute (BPM), aiming for 50% of their Heart Rate Max:
50% Intensity: ((180 – 70) x .50) + 70 = 125 BPM
In our audio workouts, when you hear Carolyn cue you for a certain percentage of your Heart Rate Max, you can calculate target zones for those percentages to help you stay at the right intensity level. Using a commercial heart rate monitor will make this much easier for you.
Carolyn will cue for intensities between 50% and 95% in her workouts