Heart rate is divided into different zones, which can be used to help you monitor the intensity of your activity. This article discusses different heart rate zones and how to increase your aerobic capacity—your body’s ability to use oxygen during exercise.

What Are Heart Rate Zones?

Heart rate zones are based on percentages of your maximum heart rate—the fastest your heart can pump with maximum exertion.

Maximum heart rate varies from person to person. To really know your maximum heart rate, you would have to measure it during all-out exercise, such as with an exercise stress test. However, a very rough estimate of your maximum heart rate can be made by using the simple formula 220 minus your age. You can then use this estimate as a rough guide for monitoring your heart rate zones.

Heart rate typically increases as the intensity of your activity increases. At higher heart rates, you are also burning more calories. Heart rate zones can be used to gauge your exercise intensity.

If you are 20 years old, your estimated maximum heart rate is 200 beats per minute (BPM). If you are 35 years old, it’s 185 BPM. If you are 50 years old, it’s 170 BPM. If you are 70 years old, it’s 150 BPM.

Using heart rate zones to monitor your activity level isn’t appropriate for everyone. If you take medications that regulate your heart rate—such as beta-blockers and calcium channel blockers—you won’t see it increase during exercise as it normally would.

Continuing to aim for a specific heart rate could lead you to overdo it. If you take these medications, consider using a different tool to assess your effort during exercise, such as the Borg Rating of Perceived Exertion (RPE) scale.

Resting Heart Rate

Resting heart rate is exactly what it sounds like. This is the number of times your heart beats per minute while you are at rest. It’s best to measure your resting heart rate first thing in the morning (before you’ve had your coffee or eaten), while you’re still in bed.

Find your pulse at the side of your neck or at the thumb side of your wrist. Place the pads of your index and middle fingers gently over the artery.

Once you feel your heart beat, count the number of beats for a full 60 seconds. You can count for 30 seconds and multiply by 2 (or count for 15 seconds and multiply by 4), but you’ll get the most accurate information by counting for a full minute.

A lower resting heart rate means that your heart doesn’t have to work as hard to pump blood to the rest of your body.

However, many things affect resting heart rate. If you’re stressed, your heart rate will likely be on the higher end. If you’re a long-distance runner, your heart pumps very efficiently and your resting heart rate might be around 40–50 beats per minute.

Target Heart Rate Zones

Heart rate zones are a useful tool for gauging your exercise intensity. First, you need to determine what your target heart rate is.

Target heart rate is calculated based on a percentage of your maximum heart rate. In general, you should exercise in the range of 50%–85% of your maximum heart rate. For a 20-year-old person with a maximum heart rate of 200, the target heart rate range during exercise is 100 to 170 beats per minute (calculated as 220 minus 20, then multiplied by 50% and 80%, respectively).

How do you decide what your target number is? If you’re just starting out, you should aim for the lower end of this range. You can also choose your target heart rate based on your exercise goals.

Target heart rate can be broken down into five different zones that help you achieve different exercise goals. Heart rate increases with each higher zone.

Zone 1: 50%–60% of Max Heart Rate

Zone 1 activities are considered “very light.” In this zone, you’ll be able to carry on a conversation while you are exercising. Examples of zone 1 exercises include walking at a leisurely pace and stretching.

Zone 2: 60%–70% of Max Heart Rate

Zone 2 activities are “light.” You can still talk while you’re exercising, but your pace has increased from zone 1. You might be walking at a brisker pace or jogging slowly.

Zone 3: 70%–80% of Max Heart Rate

In zone 3, your activity level is “moderate.” This level of exercise improves your lung and heart endurance—the length of time that you can continue to exercise without taking a break. If you’re running, you’re breathing harder. You can still speak, but you’re only able to do it one sentence at a time.

Zone 4: 80%–90% of Max Heart Rate

Zone 4 exercise is a “hard effort” activity. This type of exercise can’t be sustained for long periods of time. You’re breathing much harder, but can still speak one or two words if you have to. Zone 4 exercise improves speed and overall exercise performance for short bursts of activity, such as sprinting.

Zone 5: 90%–100% of Max Heart Rate

Zone 5 exercise is “maximum effort.” You are going “all out” at this point. You’re no longer able to speak and your activity will be very short—such as sprinting as fast as you possibly can.

How to Improve Your Aerobic Capacity

Unless you’re an athlete or training for a specific sport, you should aim for a moderate (zone 3) level of activity during exercise to improve heart health and aerobic capacity—your body’s ability to use oxygen efficiently.

The Centers for Disease Control and Prevention (CDC) recommends that adults get 150 minutes of moderate-intensity aerobic exercise per week. That can be easily accomplished by getting 30 minutes of activity, five days per week.

You might find it challenging to take your pulse during exercise. Using a device, such as a smartwatch, can help. However, heart rate monitors that use a chest strap are more accurate.

Summary

Heart rate is measured by the number of times your heart beats in one minute. Heart rate zones are based on a percentage of your (estimated) maximum heart rate and are generally separated into five zones. Exercise intensity increases as zones become higher. Heart rate zones can be used to help gauge your effort during exercise activities (and to also make sure you aren’t overdoing your workout).

Check with your healthcare provider before beginning a new exercise program. You can also discuss your medications and other underlying factors that might affect your heart rate to determine if zone training is appropriate for you.

A Word From Verywell

Being aware of your maximum heart rate can let you know that you’re pushing yourself during exercise while also respecting your boundaries. Staying within your target heart rate zone can help you improve your heart health and aerobic capacity—two things that can help you live a long, healthy life.