Learn the Easiest Way to Calculate Your Target Heart Rate Zone

Taking pulse
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When you're exercising in your target heart rate zone, you'll get the most benefits of your running or other cardiovascular activity. Your target heart rate is 50 to 85 percent of your maximum heart rate, measured in beats per minute (bpm). It is also known as the moderate-to-vigorous intensity zone. Knowing your target heart rate helps you pace properly for different types of runs.

Staying in this zone keeps you from overexerting yourself or not pushing yourself hard enough.

There are different ways to calculate your target heart rate zone, but the Karvonen Method is one of the most effective because it factors in your resting heart rate. Here's how to calculate your target heart rate zone using the Karvonen Method:

1. Measure your resting heart rate (RHR) when you first wake up. You can do this by taking your pulse for one minute while still in bed. To take your pulse, place two fingertips (not a thumb) on either the radial (on your wrist, at the base of your thumb) or carotid (neck, next to your larynx) pulse site. Take your pulse for three mornings and then average those three readings to get your average resting heart rate. Add the three readings together, and divide that number by three to get your resting heart rate, like this:

(72 + 76 + 74) / 3= 74

2. Determine your maximum heart rate (MHR).

A simple formula to get your maximum heart rate is to subtract your age from 220. This is your maximum heart rate, which is the fastest your heart can beat, measured in beats per minute. Your maximum heart rate decreases with age, so the formula adjusts for that difference. For example, the maximum heart rate for a 34-year-old would be:

220 - 34 = 186

3. Use this formula to determine your target heart rate:

Target Heart Rate = [(Maximum Heart Rate – Resting Heart Rate) × %Intensity] + Resting Heart Rate

Using the example above, here's how to calculate the target heart rate zone for a 34-year-old who has a maximum heart rate of 186 and a resting heart rate of 74:

50 percent target heart rate: [(186 − 74) × 0.50] + 74 = 130 bpm
85 percent target heart rate: [(186 − 74) × 0.85] + 74 = 169 bpm

In this example, the target rate heart zone would be 130 to 169 bpm.

How to Know When You're in Your Target Heart Rate Zone

The best way to measure your heart rate while running is to wear a heart rate monitoring device. The chest strap heart rate monitors are the most accurate. They can connect to phone apps, running watches, or activity trackers. In addition, more and more activity trackers and running watches have wrist-based LED heart rate detection. While this is an emerging technology that is less accurate, it may suit your needs.

The best kinds of monitors will alert you when you are in your chosen zone, are above it, or below it. They may do this with an audio or visual alert. If you are using a fitness app to track your workout you may be able to see how well you stayed in your heart rate zone.