The Heart Rate Zones Explained

Posted by Kayla at

Training at the right intensity is an important part of achieving your health and fitness goals.

We all know that our heart beats faster as the intensity of our workout increases, which will ultimately determine which fuel source and which energy system your body will use to generate energy. Being aware of exactly how hard you are working means that you can determine when to push yourself harder or take it down a notch. One way to do this is by being aware of which ‘heart rate zone’ you are training in.

Let me guess… you’re probably wondering what a heart rate zone is, right?

Heart rate zones are ranges that have been calculated using a percentage of your maximum heart rate (MHR), which can be calculated by subtracting your age from 220. For example, if you are 20 years old, then your MHR will be approximately 200 beats per minute. While it is possible to calculate your own heart rate zones on pen and paper, a simple way to do this is by using a heart rate monitor, such as the ones that are available in my online store.

These are the Polar FT4 and Polar FT60.

The FT4 allows you to manually set a target heart rate zone, and has visual and audible alarms which indicate when you are training outside of this zone. Zones can be set based on beats per minute (bpm) or as a percentage of your maximum heart rate. I strongly recommend the FT4 as your first heart rate monitor, particularly if you are after one that is easy to use, comfortable to wear and provides heart rate data and calorie expenditure.


Sweat with Kayla

The FT60 takes this to the next level! It includes a GPS Sensor Feature as well as a Heart Rate Monitor and Polar’s STAR Training Program. The STAR training program allows you to set a goal and the watch will provide you with weekly targets to reach. The targets are based on spending a certain amount of time in 3 different heart rate zones. If you are successful with completing the weekly targets without over- or undertraining, the program will change. Both of the watches are also water resistant!

Below I have provided a brief explanation of each of the main ‘heart rate zones’ and how they fit in with your health and fitness goals:

50-70% Low Intensity
This is the ideal range for warming up and cooling down before and after resistance training sessions as it helps to improve blood flow and circulation to your working muscles. It is also the desired zone for LISS (low intensity steady state training), such as walking. As fat metabolism requires oxygen, training in this heart rate zone ensures that you are able to take up ample amounts of oxygen, which can help with fat loss.

70-80% Moderate Intensity
This zone is great for developing endurance and burning calories. Due to energy demands, training in this zone will cause your body to rely on both carbs and fats for energy. Overall, this is a good zone for building general fitness.

80- 90% High Intensity
This zone is your anaerobic limit where your body is producing large amounts of lactic acid and is only able to maintain this level of intensity for a short period of time. It takes you out of your comfort zone and improves your VO2 Max which improves your body’s ability to utilise oxygen. Higher intensity workouts are usually a reflection of this zone, such as HIIT or my circuit workouts.

90-100% Maximum Effort
This is your upper limit of physical capacity and is the toughest zone for your body to work out in. It means you are working out as hard as you can, usually in all out sprints. This is the desired heart rate zone when completing your HIIT training. Most people can only sustain this zone for a short amount of time and it is usually only reached by advanced exercisers. If you have just started out you may not be able to reach this zone yet, and that is perfectly okay!

As you can see, being aware of your heart rate zone is an effective tool that can be used to maximise your fitness results. I encourage you to put this knowledge into practice over the next few weeks!

Kayla xx


* Results may vary. Strict adherence to the nutrition and exercise guide are required for best results.

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