How Heart Rate Monitors Work & Their Benefits To Training

What’s a heart rate monitor?
Heart rate monitors do just that, monitor your heart rate. They aren’t a new invention and technology has come a long way since their first incarnation, you don’t need to carry a huge monitor with you as you run that emits the infamous ‘beep’ tone. Luckily for the fitness community, the technology can now fit onto a strap your wear around your chest. They have grown in popularity in recent years within the fitness community, since technology has now enabled heart rate training to be open to the masses.

How do heart rate monitors work?
Believe it or not, heart rate monitors aren’t random number generators. When your heart beats, a small electrical signal is sent through the heart muscles causing a contraction – or one heartbeat. It is possible to detect this electrical signal through the skin, which is why your heart rate monitor chest strap needs to be in contact with your skin. If you want to get scientific – Electrocardiography is the name given to the recording of electrical activity of the heart.

This electrical signal is picked up by the electrodes that are in the shiny plastic part on the back of the chest strap, they pick up the signal which is then sent to the clip on transmitter. Most heart rate monitors will also contain a microprocessor that constantly monitors and calculates the heart rate. This signal is then continuously transferred wirelessly, usually by Bluetooth 4.0, Radio Waves or ANT+ to a receiver. To get a heart rate reading you need a transmitter and a receiver – the black clip on sensor is the transmitter, your phone acts as the receiver with Runtastic interpreting and displaying the data.

If you’re having problems with the reading from your heart rate monitor:

  • Ensure the sensor pads on the strap are moistened slightly with water or ECG gel for a good connection (this is usually taken care of with sweat once you’ve begun exercising)
  • Stay away from strong magnetic fields as this can interfere with the signal
  • Chest hair can prevent a good reading
  • Move the strap up, down, left or right a bit if you’re having issues with the reading
  • Ensure the strap is tight enough and the electrodes don’t move during activity
  • Old batteries can cause an inconsistent reading

How are heart rate monitors beneficial to training?
Heart rate monitors are highly beneficial to training since your heart rate is a reliable way of telling you just how hard you’re working. With a heart rate reading you will be able to tell if you’re working too hard, if you’re not working hard enough or if you’re overtraining – if you’re heart rate is unusually high on a slow recovery run, it’s time to take a few days off training. It can even motivate you, especially if you find out that your usual pace is way below what you’re actually capable of!

When you run with a heart rate monitor, you will be aiming to work out in a specific ‘zone’, or percentage of your max working heart rate to ensure you’re benefitting from your training. Don’t get the calculator out just yet, we’ve done the maths for you when it comes to working out your heart rate training zones!

If you go to, then the My Body tab followed by the Heart Rate Measurement tab, you will see the zone names with numbers underneath that are specific to you. These are worked out based on your age, resting heart rate and maximum heart rate.

The heart rate zones are as follows*:

If you are a beginner or have not exercised in a while, use the easy zone. This zone will increase your fitness levels and burn fat as well.

Fat Burning
If your aim is endurance training, use the fat burning zone. This zone will help improve the supply of energy to the working muscles. Your heart will benefit and stored body fat will be burned.

If you want to increase your cardiovascular capacity and your pace, the aerobic zone is right for you; here you will improve your muscle strength and continue to burn stored body fat.

If increasing your anaerobic threshold (AT) is what you want, use the anaerobic zone. Training in this zone will delay the point (AT) where your body cannot remove lactic acid from the working muscles quickly enough.

Red Line
Do not train in the red line zone unless you are a serious athlete, here you will increase your pace and develop speed, but be careful, you should only train in this zone for short intervals.

* If you feel the numbers for these zones aren’t correct then you can update them manually in the Runtastic App by going to Settings > Heart Rate > Edit your Heart Rate Zones.

Most training will be carried out in the Easy, Fat Burning or Aerobic zone, with the Anaerobic zone likely to be used when you do interval training.

When using a heart rate monitor with the Runtastic app, your heart rate is recorded throughout the entire workout with the option of audio feedback every mile or km with your average heart rate for that split. When you have completed your activity, you’ll be able to see how your heart rate changed over each mile or km split (along with your pace) in the pace graph tab, average heart rate for each split and the average heart rate for the whole session.

Heart Rate Monitor Runtastic

There is also a heart rate tab on the activity summary screen (on the right), that will display your heart rate reading in a pie chart, showing what percent of your activity was in each of the mentioned zones. As well as your average and max heart rate for the session. On you will also be able to see your heart rate statistics in the form of a pie chart, showing distance or time in each heart rate zone.

Runtastic isn’t the only app that can be used with a heart rate monitor! You can also use a heart rate monitor with the Runtastic Six Pack app.

As you get fitter the numbers and your zones will change since your heart gets larger and more efficient when you’ve been training for a while, so be sure to take regular readings!

So now you know how a heart rate monitor works and why they’re beneficial to training, let us know in the comments below if you a heart rate monitor has benefited your training!

Please note: We’re looking forward to your feedback and suggestions in the comments section, but we can’t answer support inquiries on the blog. Please open a support ticket if you require support, thanks!



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