Once you have determined your resting heart rate (RHR) (see part I) you can use it to calculate your target heart rate (THR) range. Here are three popular methods. Each will produce a workable starting target heart rate range, with a little variation.
1. Use a THR calculator. This is by far the quickest and easiest way. Click on one of the links below. Enter your age, click calculate and in seconds your THR range will appear. The first link uses only your age to make the calculation. The second one takes your fitness level into account, and probably produces a more accurate result.
2. Use a standard formula. Warning – this method involves math. You’ll need an old-fashioned pencil and paper and maybe a calculator. The most popular method is the Karvonen formula, which is based on your maximum heart rate (MaxHR), resting heart rate (RHR) and heart rate reserve (HRR). Here are the steps, with an example. We’ll use an example of a 40-year-old man with a resting heart rate of 60. Most methods start with the number 220, though some recommend that women use a starting point of 226.
1. 220 – your age = Max HR [220 – 40 = 180]
2. (MaxHR)-(RHR) = (HRR) [180-60=120]
3. (HRR) x (60% to 80%) = training range percent [120 x .6 =72%; 120 x .8 = 96%]
4. (Training range %) + (RHR) = your target training zone [72% + 60 =132; 96% + 60 = 156]
So for our 40-year-old male with a RHR of 60, his THR training range is 132-156 bpm (60-80%)
Using the heart rate calculator above, our same man would have a THR range of 108-144, so you can see that doing the actual math will give you a different range.
3. If you have a heart rate monitor, follow the directions on your monitor to determine your THR range. Some monitors use the same automatic calculation based on age as above; others determine a more personalized zone based on your own results during exercise.
Whichever of the three methods you use, you’ll arrive at a THR range that may or may not be right for you. Factors that influence what range is best for you is your current level of fitness, your physical ability and limitations, the type of exercise you are doing, and what you hope to achieve from your workout, whether it be for general health, weight loss, cardiovascular fitness or training for competitive events. Readers will likely need some trial and error plus additional research regarding your fitness goals, to arrive at the target heart rate that best suits your needs.
Next: How to measure your heart rate during exercise: to monitor or not.