Image source: Mio

Heart rate zone training with Fitbit, Garmin, Apple devices

Most people who exercise will tell you they want to lose weight or simply get fitter. Not many people, however, know what their heart rate is, or where it really should be. This means that often, they are not training in the most efficient way to achieve their goals. All top athlete’s heart rate train, as they know this will help them to reach their top potential in the shortest amount of time possible.

Essential reading: Guide to lowering your resting heart rate with wearables

The human heart beats more than 3.5 billion times in an average lifetime. The heart rate is not a stable value and it increases or decreases in response to the body’s need in a way to maintain an equilibrium between requirement and delivery of oxygen and nutrients. A number of different metrics can be used to describe heart rate:

  • Resting heart rateThe basal or resting heart rate is defined as the heart rate when a person is awake, in a neutrally temperate environment, and has not undergone any recent exertion or stimulation, such as stress or surprise. The typical resting heart rate in adults is 60–100 beats per minute. For endurance athletes at the elite level, it is not unusual to have a resting heart rate between 33 and 50 bpm.
  • Target heart rate: For healthy people, the Target Heart Rate or Training Heart Rate (THR) is a desired range of heart rate reached during aerobic exercise which enables one’s heart and lungs to receive the most benefit from a workout. This theoretical range varies based mostly on age; however, a person’s physical condition, sex, and previous training also are used in the calculation.
  • Maximum heart rate: The maximum heart rate (HRmax) is the highest heart rate an individual can achieve without potential for severe problems through exercise stress, and generally decreases with age. Since HRmax varies by individual, the most accurate way of measuring any single person’s HRmax is via a cardiac stress test. In this test, a person is subjected to controlled physiologic stress (generally by treadmill) while being monitored by an ECG. Adults who are beginning a new exercise regimen are often advised to perform this test only in the presence of medical staff due to risks associated with high heart rates. For general purposes, a formula is often employed to estimate a person’s maximum heart rate. The most widely cited formula for is: HRmax = 220 − age.

Another way to test your heart rate is by getting a VO2 max test done. VO2 max is a measure of the maximum volume of oxygen that an athlete can use. It is measured in millilitres per kilogramme of body weight per minute (ml/kg/min). The test can cost upwards of $100. Luckily, there is now a range of wearables which can provide you with approximate values.

Heart rate zone training

Heart rate zone training with wearablesYour body has 5 heart rate zones:

  • Moderate activity (50-60% of HRmax): Warm-up.
  • Fat burn (60-70% of HRmax): Builds aerobic endurance and teaches the body to burn fat as fuel.
  • Aerobic/Endurance training (70-80% of HRmax): Builds cardiovascular fitness and muscle strength. The top of this zone is your Anaerobic Threshold or the point at which your body stops burning fat and starts burning glucose. If you are trying to lose body fat, its important not to train too hard.
  • Anaerobic/Hardcore training (80-90% of HRmax): Increases performance speed.
  • Maximum effort (90+% of HRmax): You can usually only stay in this zone for less than one minute at a time.

When you train, you don’t burn just fat calories – your body burns glucose, too. If you are looking to burn fat, the trick is to train in a way where you are burning the most amount of fat calories possible. To burn the largest amount of fat calories, you need to work out in zones 2-3 for the majority of your workouts. To move your Anaerobic Threshold up and improve cardiovascular endurance you need to train in zones 4-5 a couple of times a week.

Want to work on speed? Pick up the pace. Looking to blast fat? Ease up to drop back into your “Fat Burn” zone.

In order to heart rate train you need a heart rate monitor. If you are very serious about heart rate training, a chest rate heart rate monitor is still the way to go. You might also want to supplement that with a dedicated GPS running watch.

For the rest of us who only find time to run occasionally, there is an increasing number of every day activity trackers that track heart rate during exercise. It is best to assume that at high intensity activity most wearables dish out ballpark estimates of your readings. And remember, even if faulty readings occur only once in a while they can still be dangerous because they can cause you to overexert yourself.

With that in mind, here are a few of our favourite fitness trackers that will help you stay in the correct heart-rate zone for your goals. Alternatively, you can always go down the GPS sports watch route.

Jump to

Fitbit Charge 4 | Garmin Vivosmart 4 | Apple Watch 6 | Withings Steel HR Sport | Garmin Vivosport | Garmin Vivoactive 4 | Fitbit Versa 3

Fitbit Charge 4

Fitbit Charge 3 or Charge 2: should you upgrade?
Image source: Fitbit

Fitbit’s flagship fitness band is a sleek looking device that delivers solid performance. Charge 4 carries over all of the features found on its predecessor, and upgrades it with built-in GPS, NFC as default and Spotify control.

As before, the device has an embedded optical heart rate sensor and its heart rate tracking is continuous and fairly accurate. It will also keep track of your resting heart rate throughout the day and display the result within the app.

Using your Fitbit tracker, start a workout as you normally would. As you begin moving, you’ll see three things: Your heart rate value, a heart, and two dashes. The location of the heart in relation to the dashes (or dots) tells you which zone you’re in.

After logging a workout, your Fitbit app shows a colorful graph depicting how much time you spent in the fat burn, cardio and peak heart rate zones. Knowing a little bit about how these zones were created can help you make the most of them.

Charge 4 also has a few new software based features you won’t find on its predecessor. This includes the ability to show training intensity on a map after a workout. This can either be in the form of pace or heart rate zones shaded throughout your route. Then there is something Fitbit calls Active Zones. This measures the intensity of your activity by rewarding you points for various heart rate zones.

Read more


Garmin Vivosmart 4

Garmin Vivosport or Vivosmart 4: activity tracker matchup
Image source: Garmin

Vivosmart 4 is a fitness tracker that packs quite a bit of high tech into its slim body. You’ll get the usual step, distance, calories, floors, heart rate and advanced sleep tracking and some more advanced metrics such as VO2Max.

Garmin has also slapped on some new features in the fourth generation device. In additional to all the usual fitness tracking smarts, Vivosmart 4 comes with a blood oxygen sensor and it will keep tabs on your body’s energy reserves to let you know when its time to push hard when to rest.

The fitness tracker is great when it comes to heart rate zone training. When you are done, the smartphone app will provide you with minute detail, including pace, heart rate (ave and max), time spent in zones, cadence, elevation, Vo2Max and more.

If you are into multi-sports and don’t mind spending a bit more, you can always opt for one if the company’s running watches.

Read more


Apple Watch 6

Heart rate zone training with wearables
Image source: Apple

The fitness tracking information on the Apple Watch is comprehensive in that it wants you to exercise for 30 minutes per day, stand for at least a minute for 12 hours and burn enough calories every 24 hours. It’ll also tell you steps and distance travelled, which is a staple of the tracker.

The latest Apple Watch was just launched. Series 6 owners will get blood oxygen readings, an improved S6 chip, a brighter always-on Retina display and more. Plus let’s not forget everything that comes as part of watchOS 7. Most notably, this includes sleep statistics for the first time.

Apple’s optical heart rate sensor is one of the best ones on the market. You can even tap into third-party apps for heart rate zone training such as Runkeeper, Strava and Runtastic. They also come with fully featured smartphone apps for more detailed information.

The Apple Watch is hands down the most advanced smartwatch you can buy today. But with each iteration, its is getting better at tracking your fitness, too. All it needs is a boost to battery life and the likes of Garmin and Fitbit will have lots to worry about.

Read more


Withings Steel HR Sport

Not everyone wants a sporty looking fitness tracker strapped to their wrist. Many people prefer a device that combines the look and feel of a traditional watch, with abilities that are evident in today’s smartwatches. This is where Steel HR Sport comes in.

Withings makes a return with Steel HR Sport
Image source: Withings

This is the second generation of the device. The upgraded version comes with the addition of Connected GPS, a Fitness Level assessment via VO2 Max estimation and better watch straps.

You still get basic fitness stats and heart rate monitoring. Real-time heart rate info is displayed on the watch during your exercise, and more detailed info including time spent in heart rate zones can be seen in the app. The watch also tracks resting heart rate, one of the most important metrics to assess overall health over time. Its swim-proof, too.

If you are looking for a classy smart device with discreet activity tracking features, the Withings Steel HR Sport is one of the best options out there.

Read more

Amazon | Withings*

Garmin Vivosport

Heart rate zone training with wearables
Image source: Garmin

Vivosport is an ultra-slim fitness band. It is slightly more expensive than Charge 3 but in addition to everything Fitbit provides the tracker comes with built-in GPS, all day stress tracking and counts reps and sets in the gym.

Along with your heart-rate zones when running, you’ll get everything you could possibly hope for 24/7 activity tracking. Garmin’s Elevate heart rate technology provides some of the best readings for a wrist-based monitor.

The GPS makes for more precise distance, time and pace tracking, along with route mapping for your runs. Vivosport will track your swims in the pool too.


Garmin Vivoactive 4

Heart rate zone training with wearables
Image source: Garmin

Vivoactive 5 is Garmin’s all purpose smartwatch, or as we like to put it a Swiss knife of activity tracking. The previous versions came only in one size but Garmin has now introduced two, a 45mm stainless steel model and a 40mm model for small wrists (4S). There’s also Venu, the exact same device but with a fancier AMOLED display.

Heart rate zone information is displayed on the always-on screen along with other detailed statistics. All in all, you’ll find 15 built-in sports profiles including new ones for snowboarding, cardio, yoga, elliptical and stair stepper. Vivoactive 4 will also let you mix it up by creating customized workouts. Other new features include VO2Max, stress/workout tracking, Pulse Oxygen readings, Body Battery and more.

Read more


Fitbit Versa 3

Heart rate zone training with wearables
Image source: Fitbit

Versa 3 was announced a couple of weeks ago. The main addition with the third generation is a slightly larger display and built-in GPS.

When it comes to features, this is a timepiece that puts fitness first. It includes everything you would expect from a Fitbit device, along with capturing real-time stats on 20 different types of activities including swimming.

The AMOLED display measures 1.58 inches, allowing for 336 x 336 pixel resolution inside a 40mm case. Its predecessor has a 1.39 inch screen with a 300 x 300 resolution.

The built-in GPS is a big step up as earlier devices in the Versa range only have Connected GPS which require your smartphone to tap into the satellite signal for location. Built-in GPS means you can go phone-free running or cycling.

Read more


Like this article? Subscribe to our monthly newsletter and never miss out!

*Disclosure: We are a review site that receives a small commission from sales of certain items, but the price is the same for you. We are independently owned and all opinions expressed here are our own. See our affiliate disclosure page for more details.

Dusan Johnson

Dusan is our dedicated sports editor which means he gets to indulge his two passions: writing and gadgets. He never leaves his house without a minimum of two wearable devices to monitor his every move.

4 thoughts on “Heart rate zone training with Fitbit, Garmin, Apple devices

  • I was a Pebble smartwatch owner when they went belly up. I was waiting on their Steel 2 with a HR monitor so when I got my refund (from the kickstarter campaign) I did a ton of research and found the Polar M600 was the best choice for me. It has a great battery life. I work out daily, sometimes just a 30 min of intervals on the treadmill but often an hour or more at the soccer field. With all of that tracking I still get 2 days of battery life. It’s waterproof and will measure my HR under water if I go do laps, and it’s a smartwatch running Android 2.0 so I can read and answer emails, text, answer calls, control my music, and track my sleeping as well (I use Sleep As Android and love it).

    Polar has a great app as well (Polar Flow) and it reminds me if I’ve sat for an hour that I need to move. The interface is great and the data is far greater than anything I got from the Misfit app (on the Pebble) or from S Health and Google Health. It not only gives you info about your activity but also about recovery, allows you to build custom workouts, and includes a social media component that, if there were more local users that do similar workouts, would be valuable.

  • Hi, I got here because I was trying to find info regarding max hear rate and how long can one stay in zone 5 because I just went into a cross country skiing 15 km competition and according to my heart rate chart for that event (see below), my avg heart rate for the 1h 22m race would have put me in Z5 at 167 bpm (with a peak at 181 bpm). I’m way above what you have on your chart. I’m 54 years old and based on previous exercises, I did set my MHR at 183 bpm, which is way higher than the 220-age and 206.9-(0.67xage) methods. First one would be 166 bpm and second 171 bpm.

    The link below is a chart of my heart rate for that race. As you can see, during the whole climbing phase (the green line), my HR was above 165 (my Z5 for a MHR of 183) and most of the time in the 170+. Am I miscalculating my MHR here or can I really stay in Z5 for over half an hour? I didn’t think it was possible. BTW, my resting HR is 55 bpm if it matters.


    • Hi there – looking at the chart – it seems very high to me. Are you sure the readings are correct? Having said that, I am not a doctor or even remotely qualified to give out medical advice…!! To be safe, I would consult a medical professional as the values do seem pretty high. My resting heart rate is similar to yours but it rarely goes above 160 when running.

      • Hi, thanks for the quick reply. I believe my heart rate chest tracker is accurate. Last Summer, I had a similar result while cycling and I took my pulse manually two different time while stopped at a red light and was within +-5 heart beats both times (accounting for accuracy error while taking pulse rate for just 10 seconds and multiply by 6).

        That was the chart at that time:

        I do have a doctor appointment in early March and I’ll ask him to recommend me someone to test my max hear rate/blood pressure professionally.

        Thanks again.


Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.