Heart rate is measured by the number of times your heart beats in one minute. Your heart rate can give information about how hard your heart is working during a particular activity. Heart rate can be measured by taking your pulse at your carotid artery on the side of your neck, or at the radial artery on the thumb side of your forearm. Count the number of beats within 60 seconds.

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.

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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.

Maximum heart rate (or maximum beats per minute) is estimated by using the formula 220 minus your age, as in the following examples:

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.

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 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.

In general, a normal resting heart rate for adults is between 60 and 100 beats per minute.

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.

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.

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 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 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.

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 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 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.

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.

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.

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.

The best heart rate zone for you will be based on your exercise goals. If you're looking to improve endurance, aim for zone 3. If you're looking to increase speed for shorter bursts of activity, aim for zones 4 or 5.

Any intensity of exercise will burn calories and contribute to weight loss. However, exercising at a moderate intensity, in zone 3, will allow you to exercise for longer periods of time. This zone also increases the amount of fat burned for energy.

Exercise is the best way to improve your resting heart rate. As your heart becomes more efficient through aerobic training, your resting heart rate will decrease.