As we know, running is an aerobic exercise which promotes and improves cardiovascular health and endurance. Indeed, running – along with cycling, swimming and cross-country skiing – is right at the top of the list of the very best forms of aerobic exercise. These sports are often referred to as ‘pure’ aerobic activities.

heart rate running machine

Aerobic literally means ‘with oxygen’ and refers to sports and exercises that require oxygen to be spread around the body as quickly as possible to fuel the muscles. The oxygen is moved via the blood and therefore your heart rate quickens and quickens to pump this fuel to the muscles working hard during the activity. As a result, regularly increasing your heart rate through exercise will strengthen your heart and reduce your chances of having any health problems in that area, as well as improving lung health and capacity.

In this article, we’ll take a look at all things heart-related while running, including:

What is ‘heart rate’?
How do I calculate heart rate?
What is a safe or unsafe heart rate?
What are heart rate training zones?
How does heart rate training work?

Read on to find out, and do some maths!

lady running through the streets monitoring heart rate

What is heart rate?

Your heart rate is the amount of times your heart beats per minute (bpm). For adults, a normal heart rate is between 60 and 100bpm while resting. Everyone has a different heart rate and it changes over time.

How do I calculate heart rate?

You can measure your own heart rate pretty simply. Just place two fingers over your pulse at your wrist and count the beats for 1 minute. Alternatively you could get a fitness tracker watch, which will do it all for you. 

What is a safe or unsafe heart rate?

As mentioned above, a normal heart rate for an adult should be between 60 and 100bpm when resting. 

If your heart rate is faster than this when resting, this could be a condition known as tachycardia. If your heart rate is faster than 100bpm and you feel dizzy, or very tired, or feel palpitations, you should contact a GP and get checked over. There are many causes of having a fast heart rate, including banal things such as an infection that can be easily treated, so don’t panic if you’re over 100bpm! 

If your heart rate is slower than 60bpm when resting, it could be a condition known as bradycardia. Again, there are many causes of this condition, which shouldn’t set alarm bells ringing, but should warrant having a quick check-up with a GP. For some very fit athletes, their heart rate can drop as low as 40bpm while resting.

What are heart training zones?

Heart training zones, or target heart rate training zones, is the bpm you are aiming to reach while training. According to the British Heart Foundation, this shouldn’t exceed 70% of your maximum heart rate

close up of runner running up steps with orange and grey trainers

You can calculate your maximum heart rate by subtracting your age from 220. So for example, I’m 39 years old. 220 - 39 = 181. My maximum heart rate is 181bpm

Therefore, according to the BHF my target heart rate training zone should be 70% of 181. Do you remember how to do maths? I don’t. So I simply type into Google ‘what is 70% of 181?’ and Google tells me that it is 127.6. And I can stop sweating, thanks Google!

As a result of this rather shameful mathematics, I am now aware that when I go out running, cycling or exercising, I should be aiming to train at 127bpm and not more. However, I could and probably would train at 115-120bpm to stay cautious and also give my heart a solid workout.

Of course, this is where a fitness watch comes in extremely useful as you don’t want to be counting your heart rate via the pulse on your wrist while running, although it is possible. 

Having a fitness watch will simplify this as well as make you aware when you’re pushing yourself too hard or not hard enough.

Steps to measure your heart rate training zone:

  1. Calculate your maximum heart rate: (220 - your age = maximum heart rate)
  2. Calculate 70% of your maximum heart rate: ask Google
  3. Consider subtracting 10 to 15 from this if you’re a beginner
  4. Use a fitness watch to monitor your heart rate while exercising

Once you are comfortable and confident with training at this level, and are feeling ready to push harder to promote heart health and stamina, you can start mixing up heart rate training zones. 

What are the heart rate training zones? 

Zone 1       - very light     - 50 to 60% Max Heart Rate

Zone 2       - light             - 60 to 70% MHR

Zone 3       - moderate    - 70 to 80% MHR

Zone 4       - hard            - 80 to 90% MHR

Zone 5       - maximum    - 90 to 100% MHR

How does heart training work?

Heart training differs from other forms of training techniques because it focuses on your heart beats per minute over a period of time rather than distance covered or speed.

Here's an example of heart rate training if you were running for one hour:

  • Zone 1 for 10 mins
  • Zone 2 for 30 mins
  • Zone 3 for 10mins
  • Zone 4 for 8mins
  • Zone 5 for 2mins Stop

Heart training has many benefits, but may not be as effective for improving speed or covering distances, although in time it will improve these things as a matter of course. Better cardiovascular health, lung capacity and overall fitness will get those times up and increase your stamina in the long run.

Heart training benefits:

  • Cardiovascular health improvement 
  • Increase in endurance 
  • Reduction of recovery time
  • Less tiredness after running
  • Less chance of minor injuries
  • 70% (and above) of maximum heart rate is the fat burning zone
  • Promotes the body into using fat for fuel (important for long-distance running) 


Heart rate training zones are a great way for beginners to improve their fitness without running into trouble. However, for more experienced runners, heart rate training should be incorporated into your training schedule to monitor and improve cardiovascular health and endurance for upcoming races or long-distance challenges.