Active heart rate is a measurement of a person’s heart activity during exercise. People can use it to optimize their workouts by ensuring that their heart rate stays within the ideal range. This measurement can also indicate a person’s overall fitness level.

A person can quickly calculate their ideal active heart rate by subtracting their age from 220. This calculation provides the person’s maximum heart rate.

Their target heart rate will be between 64% and 76% of that number during moderate intensity exercise and in the range of 77–93% for vigorous intensity exercise.

In this article, we look at active heart rate in more detail, including what it means and how to measure it.

A man pausing during outdoor exercise on a basketball court to measure his active heart rate using a device on his wrist. He is wearing a green hat, earphones, and a blue sweater.Share on Pinterest
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A person’s heart rate is a count of how many times their heart pumps within 1 minute. People measure heart rate in beats per minute (bpm).

A person’s active heart rate measures how fast the heart is beating while they exercise. Active heart rate is typically much higher than resting heart rate, as aerobic exercise causes the heart to beat faster.

Active heart rates can vary from person to person. The measurement will change depending on:

  • the type of exercise
  • the intensity of the exercise
  • the person’s current level of fitness
  • the air temperature, as being hotter increases heart rate slightly
  • other factors, such as age, medications, or health conditions

Active heart rate is not the same as maximum heart rate. The maximum heart rate is the highest rate at which the heart can beat, and it varies by age.

People can measure their own heart rate during any given exercise by following the steps below:

  • Stop the exercise temporarily and immediately place the index and middle fingers firmly on the artery on the thumb side of the wrist.
  • Concentrate on feeling the pulse in the wrist.
  • When it is possible to feel the pulse, use a watch or the timer on a smartphone to count the number of times the heart beats in 60 seconds. Alternatively, count the beats for 30 seconds and multiply the number by two.

The number of beats per minute will tell someone their current heart rate, which can help them determine whether they are exercising at the right level of intensity.

People can also monitor their activity level via perceived exertion, which involves noticing physical signs of exertion in the body. For example, a person can consider how fast the heart rate feels and look for other signs of exertion, such as sweating and muscle fatigue.

Anyone experiencing drastic changes in heart rate, physical discomfort, or pain while exercising should stop the exercise and speak with their doctor.

The ideal active heart rate for someone will depend on their age. The following calculations can provide a rough guideline for the average adult.

Moderate intensity activity

A person needs to determine their maximum heart rate in order to calculate their ideal active heart rate. They can do this by subtracting their age from 220.

For moderate intensity exercise, the Centers for Disease Control and Prevention (CDC) recommend an active heart rate of 64–76% of the maximum heart rate.

Therefore, a person can take their maximum heart rate and multiply it by these percentages as decimals: 0.64 and 0.76.

For instance, if a person is 20 years old, the steps would be:

  • 220 – 20 = 200
  • 200 x 0.64 = 128
  • 200 x 0.76 = 152

So, for moderate intensity activity, a 20-year-old person would need to aim for a heart rate of 128–152 bpm.

Vigorous intensity activity

Vigorous intensity activity demands more work from the heart, so a person’s ideal active heart rate will be higher. The CDC recommends an active heart rate of 77–93% of the maximum.

A person can calculate the ideal range during vigorous intensity exercise by repeating the same steps as above but swapping the decimal numbers for 0.77 and 0.93.

For example, a 20-year-old person would calculate:

  • 220 – 20 = 200
  • 200 x 0.77 = 154 bpm
  • 200 x 0.93 = 186 bpm

They should, therefore, aim for an active heart rate of 154–186 bpm.

A low active heart rate can mean that a person is not exercising intensely enough to benefit from the activity. For example, if a person is walking or jogging slowly, their heart rate may not be within the ideal range.

People with no underlying conditions who notice that they have a low active heart rate may want to increase the intensity of their workout to get it within the recommended range.

However, if someone is new to regular exercise or has a health condition that affects their ability to exercise, it may be better to aim for the lower end of the range initially.

The American Heart Association (AHA) recommends that these individuals aim for 50% and gradually work upward as they develop more strength and stamina.

A high active heart rate can mean that a person is exercising too vigorously. If a person finds that their heart rate is higher than the recommended range, they should slow down or take a break.

Although it is beneficial for workouts to be somewhat challenging, it is not healthy to push the heart too hard.

Other factors can influence a person’s active heart rate, potentially pushing the rate lower or higher than is ideal. They include:

  • Overall health: A person’s general health status and current fitness level have a significant influence on heart rate. If a person is not used to exercise, their heart may have to work harder during physical activity, causing their heart rate to be higher.
  • Medications: Some medications, such as beta-blockers, can lower the heart rate. However, other medications can raise it.
  • Temperature: Heat and humidity can raise the heart rate by about 5–10 bpm, according to the AHA.
  • Emotion: Stress, anxiety, anger, and even happiness can also raise the heart rate.

A person’s body weight typically does not affect heart rate very much. People with obesity may have a slightly higher heart rate, though.

Getting the heart rate into a healthy range during exercise typically involves exercising in a way that is challenging but not strenuous. There are several ways people can keep track of this metric during exercise, including:

  • taking breaks to check the pulse
  • wearing a device on the wrist, such as a fitness tracker, that measures heart rate
  • using fitness equipment that measures the heart rate

People can also take note of how they feel during exercise. If a person’s bpm falls within a healthy range, and they feel that the current level of exercise is acceptable, they can continue as they were.

If the heart rate is too low or too high, people can try adjusting:

  • the speed of exercise
  • the number of repetitions
  • the type of movement, e.g., the stroke a person is using while swimming
  • the amount of resistance or elevation, if using an exercise machine

Anyone who notices that they have a very high or low heart rate, either at rest or during exercise, should speak with a doctor.

People should also contact a doctor if they experience other symptoms during or after exercise, such as:

  • dizziness
  • feeling faint
  • shortness of breath

It is essential to stop any form of exercise that feels uncomfortable or painful, even if the heart rate is within a healthy range.

Active heart rate is a measurement of a person’s heartbeat during physical activity. People can use it to determine whether they are exercising at the optimal intensity.

The healthy range will vary depending on the individual. If a person is concerned about their heart rate during or outside of exercise, they should speak with a doctor promptly.