One size doesn’t fit all when figuring your target heart rate zone

Heart Rate

You’re probably familiar with the traditional method for figuring your Target Heart Rate (Target HR); 220 minus your age multiplied by the Target HR percentage. Well…the problem with this method is that it doesn’t factor in your level of cardiovascular fitness. For example, a 40 year old with a Resting Heart Rate (Resting HR) of 60 beats per minute (bpm) would have the same Target HR as a 40 year old with a Resting HR of 100 bpm.

The Karvonen Formula

If you want a more personalized and accurate Target HR you can use the Karvonen Formula. The Karvonen Formula is a Heart Rate Reserve (HR Reserve) formula, and it’s one of the most effective methods used to calculate Target HR. The formula factors in your Resting HR, therefore, you’ll need to find out what your Resting HR is by doing the following:
First thing in the morning, before getting out of bed, take your pulse on your wrist (radial pulse) or on the side of your neck (carotid pulse). Count the number of beats for 60 seconds. Now you have your Resting HR.

To find your Target HR using the Karvonen Formula you need to determine your Maximum Heart Rate (Max HR), Resting HR, and HR Reserve. The HR Reserve is simply the difference between Max HR and Resting HR.

The calculations for the Karvonen Formula variables are shown below:

220 minus (-) your age = Max HR
Your heart rate at rest = Resting HR
Max HR – Resting HR = HR Reserve
(HR Reserve x Training%) + Resting HR = Karvonen Formula

So with the Karvonen Formula, if you’re 40 years old with a Resting HR of 60 bpm, your 65%-85% Target HR training zone would be 138 to 162 bpm. And with the older traditional formula it would be…117 to 153 bpm. That’s a huge difference!

Karvonen Formula Solution:

Max HR = 180
Resting HR = 60
HR Reserve = 120

65% Target HR using the Karvonen Formula is (120 X .65) + 60 = 138 bpm
85% Target HR using the Karvonen Formula is (120 X .85) + 60 = 162 bpm

Here’s a tool that’s done all the calculations for you, all you need to do is put your age and resting heart rate…then click “calculate”. Karvonen Heart Rate Calculator

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