Everything You Need to Know About Heart Rate Training Zones

by Zach Nehr

Blog ▸ Everything You Need to Know About Heart Rate Training Zones

One of the best ways to measure your training is heart rate – it is a straightforward metric that you can count with your own hand. Heart rate is an excellent representation of how hard you are working, and you can use heart rate training zones to measure your training efforts and intervals.

However, heart rate can be tricky – it varies from person to person, and many typical methods for calculating heart rate training zones are oversimplified and inaccurate. Some measurements use arbitrary numbers based on age or theoretical maximum heart rate.

We’ve created the heart rate training zone calculator below based on a superior method of calculating training zones that, in our experience, get far more accurate results for running, triathlon training, and cycling training zones. Check it out!

In the rest of this post, we’ll also cover much more – First, you’ll plug your numbers into our Heart Rate Training Zones Calculator. Then, we’ll explain the approaches to heart rate-based training and which we think is best. Lastly, we’ll help you use your numbers to create your own heart rate-based training plan.  

Heart Rate Training Zone Calculator

What Are Target Heart Rate Training Zones?

Target heart rate zones are a structured way of gauging your exercise intensity based on your heart rate. The most common model for heart rate zone training is the five-zone model, where Zone 1 is the lowest heart rate and Zone 5 is the highest. However, remember that this is not the exact method we use to calculate your heart rate training zones – more on that below in Karvonen Heart Rate Training Zones.

Here is a quick breakdown of primary heart rate training zones: 

  • Zone 1: <60% of max heart rate (HRmax)
  • Zone 2: 60-70% of HRmax
  • Zone 3: 70-80% of HRmax
  • Zone 4: 80-90% of HRmax
  • Zone 5: 90-100% of HRmax

Later in this article, we will describe each of these zones in greater detail. We’ll also tell you the best heart rate training zones and what zone you should target for weight loss.

Of course, you’ll need to know your maximum heart rate to move on to the next step.

How to Calculate Your Maximum Heart Rate

It has been wildly disproven that your maximum heart rate equals 220 minus your age. HR is so individual that it’s difficult to simplify it into an equation. 

The Tanaka method has shown more accurate results for predicting maximum heart rate. In comparison, the Gulati method is explicitly designed for women.  

Three common methods for calculating your maximum heart rate:

  • Tanaka method: 208 – (0.7 x age)
  • Gulati method (for women): 206 – (0.88 x age)
  • Max heart rate test

You should perform a maximum heart rate test to get the most accurate number for your maximum heart rate. The test will be painful, but it will be over fast! Our test is for runners, but you can also perform a similar test for cycling.

Max HR Test Protocol

Use a heart rate chest strap – as opposed to a wrist-based heart rate monitor – to get accurate data during the following test:

  • 2 miles easy jog warm-up
  • 1 mile at a strong tempo pace to bring the HR up
  • 400m at maximum effort
  • 400m where you push harder at every 100m intervals to get the maximum HR possible

Find the maximum heart achieved during this run (in beats per minute bpm), then enter 2bpm higher than the highest heart rate you achieved during this test. We like to enter two beats per minute higher because you could probably have pushed a little harder if there was a gun to your head.

You can perform a similar protocol on the bike with a cycling maximum heart rate test. A ramp test done on an indoor trainer is the best max heart rate test for cycling, as it allows you to continually build your effort until exhaustion. Again, use a heart rate chest strap to get accurate data for this test:

  • 5mins easy warm-up
  • Start by riding at 100W for one minute
  • Increase your target power by 20W every minute until failure
  • 5mins easy cool-down

Note: if you don’t have a power meter, try starting with the first minute at a super easy pace. Use RPE to gauge your effort, starting at a 1 out of 10 and increasing your effort by one notch per minute.

Dig deep in the final minute of your test and pedal until you can’t turn the cranks anymore. Your peak HR from this test is your max heart rate for cycling.

Everything You Need to Know About Heart Rate Training

Once you know your maximum heart rate, it’s time to use your newfound knowledge to use the calculators, craft a training plan, and get faster! Here’s what we’ll cover in the rest of this article:

  • Drawbacks of Traditional Training Zone Calculators
  • Karvonen Heart Rate Training Zones
  • Best Heart Rate Training Zones
  • Different Approaches to Heart Rate-Based Training
  • Polarized vs Pyramidal Training
  • How to Build a Heart Rate-Based Training Program

Drawbacks of Traditional Training Zone Calculators

As we’ve mentioned, most heart rate training zone calculators like the MAF Method or Age-Related Methods generate zones based on some or all of the following factors:

  • Age
  • Maximum heart rate in a max HR test
  • Your answers to some yes/no questions

The problem with these methods of calculating training zones is that the factors that go into the calculations are entirely arbitrary and, in our experience, generate inaccurate results in roughly 20-30% of the users of the calculators. We have a better option.  

Karvonen Heart Rate Training Zones

We use the Karvonen Formula to generate the heart rate training zones we recommend for endurance athletes because it appears to be far more accurate for many athletes. This method generates very similar training zones to those found in lab results. We have yet to meet an athlete who didn’t see it as accurate or more precise than typical calculators.

The Karvonen Formula seems to be a superior method of generating training zones because it’s based on the athlete’s physiology. Depending on your fitness level, you may have an abnormally high or low heart rate. At the same time, training and this formula accounts for that.

Instead of assigning training zones based on random numbers, the Karvonen Formula takes your unique physiology into account. The critical difference between the Karvonen Formula and other heart rate training zone calculators is the addition of resting heart rate.

Our heart rate training zone calculator uses both maximum and resting heart rate to generate your heart rate training zones. Assuming you know your maximum heart rate, you need to know your resting heart rate.  

Karvonen Formula

The Karvonen Formula uses your max HR, threshold HR, resting HR, and percentage of exercise intensity to create your unique zones. This is the exact formula:

Threshold heart rate = [(Maximum heart rate – Resting heart rate) x %Intensity] + Resting heart rate

THR = [(MHR – RHR) x %Intensity] + RHR

For example, this is what your zones would look like with a maximum heart rate of 180bpm and a resting heart rate of 70bpm.

  1. Zone 1: 125-136bpm
    • Warm Up Zone
    • 50-60% Intensity
  2. Zone 2: 136-147bpm
    • Fat Burn Zone
    • 60-70% Intensity
  3. Zone 3: 147-158bpm
    • Aerobic Zone
    • 70-80% Intensity
  4. Zone 4: 158-169bpm
    • Anaerobic Zone
    • 80-90% Intensity
  5. Zone 5: 169-180bpm
    • VO2max Zone
    • 90-100% Intensity

How to Find Your Resting Heart Rate

Wear a fitness watch with a built-in heart rate monitor for a few nights while you sleep. Take the lowest overnight resting heart rate you measured while sleeping and enter that as your resting heart rate.

silver aluminum case apple watch with red sport band

Best Heart Rate Training Zones

Here’s where we start putting it all together. We’re going to run you through each of the heart rate training zones from 1 to 5 and tell you exactly when to use them

  • Zone 1:
    • Very light exercise, used for warm-ups, cool-downs, and active recovery
    • 30-40% of total annual training time
  • Zone 2:
    • Light exercise, burns fat and builds endurance
    • 40-50% of total annual training time
  • Zone 3:
    • Moderate intensity exercise that improves aerobic fitness and muscular strength
    • 10-15% of total annual training time
  • Zone 4:
    • High-intensity exercise that improves aerobic and anaerobic thresholds
    • 5-10% of total annual training time
  • Zone 5:
    • Very high-intensity exercise that develops fast-twitch muscle fibers. Only meant for short-duration sprints and anaerobic efforts 
    • 5-10% of total annual training time

Zone 1

Zone 1 is the easiest training zone that is reserved for easy training and recovery rides. You can also target Zone 1 in long-duration training sessions, especially for the longest workout in your training week. 

Zone 2

Zone 2 should also feel easy, but it is noticeably harder than Zone 1. In Zone 2, you will feel like your foot is constantly on the gas, but only lightly. The vast majority of endurance training occurs in Zone 2 for two reasons:

First, Zone 2 is hard enough to stimulate more fitness gains, mitochondrial growth, etc., compared to Zone 1. Second, Zone 2 is still below your aerobic threshold, which is the point at which blood lactate begins to increase markedly. Above your aerobic threshold, you burn much more energy, damaging your muscles and adding significantly more fatigue to your body.

Of course, this damage can be good when handled in small doses (more on this in a minute). But for most of your endurance training, you should target Zones 1 and 2 below your aerobic threshold – this will allow you to continue training every day without building up too much fatigue. 

Zone 3

You will find your triathlon race pace somewhere around Zones 3 and 4, or maybe even Zone 2 for an Ironman. Zone 3 will be your “tempo” pace, as many athletes prefer to call it. This is a moderate intensity that you can hold for a couple of hours, but it is incredibly draining.

man in blue tank top running on track field during daytime

Zone 4 

Within Zone 4 is your lactate threshold, or the point that blood lactate begins to build up at an unsustainable pace. Your heart rate lactate threshold (LT) can be comparable to your functional threshold power (FTP) on the bike – your LT or FTP is the hardest pace that you can sustain for an hour. These intervals are very hard, and most Zone 4 workouts consist of intervals lasting around 8-20 minutes. 

Zone 5

Zone 5 consists of very hard, short-duration intervals designed to increase your anaerobic capacity and sprinting ability. You may have heard of 30/30s – a session consisting of alternating 30 seconds “on” at VO2max and 30 seconds “off” in Zone 1. These sessions are very painful but short. 

Most Zone 5 workouts target your VO2max which is a training zone above your anaerobic threshold. At your maximum, you can only hold your VO2max for a few minutes, which is why Zone 5 intervals are so short. Not all endurance athletes use Zone 5 training, but it is increasingly popular among short-distance triathletes and time-crunched athletes. 

Best Training Zones For Weight Loss

Zones 1 and 2 are the best heart rate training zones for weight loss since they burn the highest percentage of fat compared to carbohydrates. In Zones 3, 4, and 5, you will burn more calories because of the higher intensity, but these workouts will also be much more fatiguing. 

High-intensity interval training (HIIT) is sometimes used for weight loss since it can stimulate your metabolism. However, you’ll need to be careful with this approach since it takes a significant amount of carbohydrates to fuel these sessions. 

A long ride in Zones 1 and 2 will burn through far fewer calories than a short ride that includes 30/30s at VO2max. 

Different Approaches to Heart Rate Training

Once you have your target heart rate training zones, you can start planning out your training. But, you’ll still need to consider how much time you want to spend in each zone. 

There are a few different schools of thought on using heart rate for training, but here we are going to focus on the big two: polarized and pyramidal. 

person holding pencil near laptop computer

Polarized vs Pyramidal Training

The polarized training model is one of the most popular in all endurance sports. It is great for time-crunched athletes and busy people (which, aren’t we all?), and it is fun and stimulating. However, polarized training is not always the best for triathletes because of its use of very high-intensity intervals. 

We recommend the pyramidal training style for heart rate-based training because it gives you more time to focus on triathlon race pace intervals. The pyramidal training model also gives you lots of time to prepare for your goal race using race pace intervals. 

In the pyramidal style of training, you should spend 75% of your time in Zones 1 and 2, and the remaining 25% of your time in Zones 3, 4, and over the course of a training year. 

One of the main benefits of the pyramidal training model is the ability to get comfortable at race pace. In most triathlons, race pace will be in or around your Tempo Zone, or Zone 3 in most models. 

The Polarized Training model neglects Tempo and Zone 3 in training, which means that you’ll never really experience it in training. It can be a shock on race day to go out at an intensity that you’ve ever trained at before.  

Polarized training is most popular for cycling, running, and other endurance sports because it is a better fit for the demands of the sport. In cycling and running, there are lots of sprints and accelerations with easy pacing in between. And in shorter races, there is no easy part – you are riding or running at threshold for the entire race. 

Triathlon training is different because so many of our race pace intervals will be done in Zones 3 and 4. Thus, the Pyramidal training model is best for triathletes training by heart rate. 

How to Build a Heart Rate-Based Training Program

When building a HR-based training program, you should consider both macro- and micro-cycles. Macrocycles are multi-month blocks of training which we’ll detail below. Micro cycles are your weekly and daily training, including each specific workout.

Your training should never be the same all year round and that’s why we recommend dividing your year into macro cycles. Your weekly volume and intensity should change depending on the training cycle, and we like to use these four: 

  • Off-season
  • Base
  • Build
  • Race

Beginning with the off-season when training is at a minimum, you should be spending 90% of your training time in Zones 1 and 2, and just 10% of your time in Zones 3, 4, and 5. With each new training cycle, the intensity distribution will shift towards more time in Zones 3, 4, and 5 with less time in Zone 1 and 2. 

Here’s an example: 

  • Off-season: 90% Zones 1 and 2; 10% Zones 3, 4, and 5
  • Base: 85% Zones 1 and 2; 15% Zones 3, 4, and 5
  • Build 75% Zones 1 and 2; 25% Zones 3, 4, and 5
  • Race: 70% Zones 1 and 2; 30% Zones 3, 4, and 5

With these shifts in intensity, you will spend more and more time at race pace. You can use your heart rate zones to monitor each of your training sessions throughout each period. For most triathletes, we recommend two main workouts each week: one short workout and one long workout.

Your short workout should consist of higher heart rate intervals, such as Zone 4 or Zone 5 intervals. As for the long workout, you should focus on increasing the amount of time that you spend in Zone 2 each week. This can be a 4-hour bike ride in Zone 2, for example.

Example Training Week

Here is an example week using a heart rate-based training program (from our Beginner’s Guide to Half Ironman Training): 

  • Monday: swim – 40 mins total. 2×200 at 85% effort with 30sec rest
  • Tuesday: bike – 55 mins total. Repeat five times: 5mins Zone 4, 3mins easy spin.
  • Wednesday: run – 60 mins total. 9×2.5mins Zone 5, with 2mins easy jog rest between.
  • Thursday: bike – 84 mins total. Repeat four times: 4.5mins Zone 3 with 60-70 cadence, 4.5mins Zone 3 with +100 cadence, 4.5mins Zone 4 with 60-70 cadence, 4.5mins easy spin.
  • Friday: swim – 40 mins total. 2×250 at 85% effort with 30sec rest.
  • Saturday: bike and brick run – 130 mins total. 3x10min Zone 4 (above race pace) with 5min easy rest intervals between. Run – 30 mins total. 30min run Zone 3 or 4 (slightly above race pace).
  • Sunday: run – 75min easy run in Zone 2.


You’ll now have accurate heart rate training zones that you can use in all of your endurance training. Perform these tests every three months to keep your heart rate training zones up to date and you’ll have your training dialed in!


Zach Nehr

Zach Nehr

Zach has a degree in Exercise Science and Psychology. He is a certified coach, Cat 1 cyclist, and is a freelance writer having been published in many of the worlds largest endurance sports publications.

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