Fat burning is one of the main reasons people start workout out in general. It is also one of the more challenging things about exercising, especially since it requires a certain amount of prior knowledge to be done right. Many people try a lot of different strategies, from which some work and some simply don’t. What if I told you that you can use your heart rate monitor for fat burning? That’s right, tracking your HR and getting into the right heart rate zone can be one of the easiest ways to guide your body into using mainly fat-stored energy.
In this article, I will go through some of the ways to calculate your ideal fat-burning heart rate, show you which exercises are good to maintain it in that zone, and we will also discuss a few other things that you can do to help your body burn fats.
Figuring Out Your Fat-Burning Heart Rate Zone
The heart rate is a good metric to measure the intensity of your workout. When you are at rest, your heart rate should be between 60 and 100. When you start exercising, it will go up proportionally to the efforts you are putting in.
When your heart rate increases, it goes through 5 zones, with zone 5 being the higher and most intense. These heart rate zones are calculated as a percentage of your maximum HR (called HRMax which is 220 minus your age). Here are zones 1-5:
- Zone 1 – 50-60% of your HRMax
- Zone 2 – 60-70% of your HRMax
- Zone 3 – 70-80% of your HRMax
- Zone 4 – 80-90% of your HRMax
- Zone 5 – >90% of your HRMax
Different heart rate zones require your body to burn different types of nutrients for its fuel. Lower intensity training (in zone 1) only uses carbohydrates for energy. Extremely high-intensity workouts (in zones 4 and 5) also tap primarily into the carbohydrate fuel supply.
The difference between carbohydrates and fats when it comes to energy supply can basically be boiled down to the speed with which they are used by the body. Carbohydrates are extremely easily used by your body and can be turned into cell energy really fast. This is why your body uses them when you really push it to its limits. However, carbs aren’t very energy-rich compared to fats, which have more than twice the calories per gram. This is why your body prefers burning fats in zones in which your body needs a lot of energy but also has the time to process them.
The % of your HRMax where this can occur is anywhere between 60% and 70%, so in zone 2 of your heart rate.
Now, since you know in which zone you have to be, all you have to do is calculate your HRMax and figure out where your Zone 2 is. As I already pointed out, you can do that by taking 220 and subtracting your age from it.
For instance, if you are 30 years old, your HRMax is 190. Your Zone 2 is 60-70% of HRMax, meaning 114-133BPM (beats per minute).
You can use online calculators if you aren’t sure about your personal zones.
Heart Rate Measuring Tools
There are three methods that are most commonly used to measure your heart rate:
- Traditional tracking
- Wrist trackers (monitors)
- Chest strap monitors
Traditional tracking is what most physicians use to measure your heart rate when you visit the doctor’s office. It is done by placing your index and middle fingers over the carotid artery in your neck or the arteries in your wrist. You can also do that by placing your hand flat on your chest and feeling out your heart’s beats. Then, you can take a quick measure by counting the beats for 6 seconds and multiplying them by 10. You can also count beats over 10 seconds and multiply that by 6. The most accurate way to get your HR with just your hands is to count all the beats within a minute.
Wrist trackers are a valid alternative to measuring your HR manually. They are fairly accurate (depending on the quality of their sensor) and give you a live read on your pulse. There are also models that tell you in which HR zone you are training, based on the data that you’ve entered about you. You can learn how to get the most out of your fitness tracker on my full article on the topic.
These devices come with a plethora of other advantages as well. They can measure elevation changes, steps taken, calories burned during your workout, stairs climbed, and other metrics.
Chest straps monitors are my favourite out of all the methods of checking your heart rate. They are extremely accurate because they are placed directly over your heart and detect the vibrations from each of its beats. Their disadvantage is that they have to be connected to a wearable device or your phone. They can also be uncomfortable to some people or cause a sensation of tightness around your chest if not adjusted properly. Luckily, newer models are made out of soft materials and give you a surprisingly large amount of data about your workout.
If you are looking for a good waterproof fitness tracker, head over my Buyer’s Guide which has all the information you need plus the best models for this year!
Burn The Right Type Of Calories
Usually, the higher the intensity of your workout, the more calories will your body burn. While that is correct, there is one major detail that you need to take into account. I already mentioned that your body taps into different fuel sources depending on how much energy it needs and how fast it needs it.
Getting your HR near your HRMax limit will burn more calories but you won’t be burning primarily fat, which is the whole reason why the fat-burning zone is way lower than your maximum HR.
During intense workouts, your body will burn your short-term carbohydrate stores which were most likely accumulated during your last meal, which is one of the reasons you feel rather hungry after an HIIT (high-intensity intervals training).
To tap into your body’s stored fats source, you will need to keep lower intensity activities in your fat-burning zone for a longer duration. That will allow the body to utilize its fat-burning metabolic pathways and start reducing its stored fats.
Choosing The Ideal Workout
Choosing the proper intensity level and workout to get to your fat-burning zone depends on your skill level and experience. If you love running and have been doing it for a while, it might take a little more effort to reach 70% of your HRmax and maintain it for long enough.
Still, if you are a beginner, there are a lot of exercises which offer moderate heart rate that provides excellent fat-burning opportunities. These are:
- Walking your dog
- Taking the stairs
- Taking your bike to work instead of driving
These might not seem like a lot but can easily get untrained people to their second HR zone and if done for enough time can be an excellent choice for fat burning.
If you are a beginner runner, you need to run at a slower pace for longer periods in order to not let your heart go above 70%. Remember, the higher your heart rate goes, the fewer fats your body burns and the more it will prefer carbohydrates over fats.
Consider starting with a brief walk to warm your body up and show it that this won’t be an intense workout. The more you progress into running, the more you will be able to move and push yourself and still stay in the fat-burning zone of 65-75% of HRMax. This is because your heart will become stronger and stronger and it will take less and less effort to pump blood even when you’re exercising. This is why inexperienced people can get into their Zone 2 by just taking a long walk, while experienced runners will have to run for 20-30 minutes to reach more than 70% of their HRMax.
If you are new to running, you can follow a rule of not increasing your weekly mileage by more than 10% each week. This will pretty much be on par with your progress if you run regularly (3-4 times a week) and will prevent unwanted injuries.
If you want to train in your specific fat-burning zone through running, check out my article on how to create your own running plan based on your needs.
Using your heart rate monitor for fat burning might be one of the better training decisions you can take. In order to burn fats using heart rate zones, you will need to accurately measure your heart rate throughout the workout. This can be done in a lot of ways but the fastest method to get live data is through a heart rate monitor. These can be either a wrist fitness tracker or a chest-strapped monitor that measures your heart’s beats. When you have quick access to that data you will be able to accurately adjust your workout in order to stay within 65-75% of your maximum heart rate and let your body tap into its fat stores for its energy.