Setting Training Zones: How (And Why) To Do It Properly

Updated July 10, 2025 01:19PM

Establishing and using training zones can give triathletes more control over workout intensity and make common training pitfalls, such as overtraining, less likely. Knowing how hard you should be going helps keep you in the target intensity and effort for a workout. However, establishing accurate triathlon training zones takes time and involves collecting data, like power, heart rate, pace, and perceived effort. Learning to properly train in those zones once you establish them also takes time; there is a bit of a learning curve when you start trying and setting training zones—especially when they are heart rate training zones.

What Are Triathlon Training Zones

Training zones, in essence, are a way to measure how hard or easy you’re going in workouts. While different coaches use different numbers and definitions of zones, most of the time Zone 1 is the easiest—whether measured by perceived effort, heart rate, pace, or power output. Zones are levels broken down one or more metrics that define

One of the most common zone break downs is into five training zones—though there are also systems that use just three and those that use seven, where the highest number is the hardest zone. Be sure to use the same zones and zone definitions as your coach or as the prescribed workouts.

We’ll talk more below about how to establish or set training zones below, but most coaches and systems use a test that allows you to establish a threshold effort (typically zone 4 in a five zone system) and then extrapolate from there. There are, however, also different definitions of lactate threshold v. functional threshold power v. ventilatory threshold. Additionally, the zones vary across sports—your threshold heart rate for running will be different than for biking.

Don’t Make These Mistakes When Setting Training Zones

There are two common mistakes triathletes—and athletes in general—make when setting training zones: using only heart rate and using an equation to find your maximum heart rate. Heart rate is actually a more sensitive metric than you may realize. First, you must take into account that heart rate is very specific to each person. Second, you must understand that there are a number of factors that can change your heart rate from day-to-day and activity-to-activity, including the weather, your hydration levels and, for triathletes, which discipline you’re doing at that moment. For example, when swimming, your body position and the water result in a much lower heart rate than you’ll produce when you’re running.

“It’s very much dependent on the person’s physiology,” said Rhys Jones, a seven-time Welsh triathlon champion, sports physiologist and coach at Jinx Sport. “It isn’t just a simple equation… There are a lot of people that have very exceptionally high maximum heart rates and some with very exceptionally low maximum heart rates. That is very much predisposed by genetics and manipulated by training. Using heart rates as a sole measure of training zones is very subjective.”

That equation Jones is referring to is one even the Centers for Disease Control and Prevention (CDC) shares, suggesting that in order to find your maximum heart rate, you simply take your age and subtract it from 220. As Jones notes, however, coaches—including famed endurance coach, TrainingPeaks founder and author Joe Friel—will tell you that this equation is not reliable. Jones adds that coaches will establish a training history and athlete type prior to using heart rate to set training zones.

It is important to know that when it comes to training zones, heart rate isn’t the only metric that matters. This is especially true for those when you aren’t able to collect heart rate data and need other metrics to go off of. The most common addition to a training zone is rate of perceived exertion (RPE), which will help your body learn to train and race by feel. Additionally, many coaches will use power on the bike or pace on the run or swim as additional metrics.

One of the benefit of using power, pace, and perceived effort in addition to heart rate is that heart rate can often lag—ie. it takes some amount of time for it to rise as you do work. “You must give your heart rate time to get to the level,” said Mandi Kowal, founder of TRI-Umph Today Coaching. “One must not charge out of the gates and expect their heart rate to be in their zone within the first minute; give it 5-10 minutes to steady off. One must be patient.”

This patience applies to setting triathlon training zones, too, where testing anxiety and lack of data can have an impact on the accuracy of zones.

Why Triathletes Need to Set Multiple Training Zones

Because there can be differences in heart rate by discipline, triathletes should establish multiple training zones. This can be done through different tests for each discipline, all using heart rate, RPE and, if possible, power or pace. Heart rate tends to be highest running and lowest swimming for the same effort. Each discipline also comes with different variables. For instance, Jones said it is much easier to control a swim test or workout, for example, especially if you train in the same pool, at the same time of day, maintaining the same water temperature and easily measurable distances.

“Heart rate zones will vary depending on the exercise,” reiterates Kowal. “With swimming, it’s lower due to the temperature of the water, the fact that the body is horizontal, and the fact that one is not fighting gravity. When you look at running versus biking, in running your body is using more muscles to propel oneself, which makes your heart work harder.”

Read This Before You Test for Training Zones

If this is all TL;DR and you’re just here for the tests, we hope the big letters in the header for this section got your attention. That’s because you need to keep this in mind: testing takes practice. Don’t expect to do each of these tests once and boom, you have your training zones that will last you through the rest of your triathlon career. Unfortunately, it’s not that easy (it is never that easy).

“Ideally, when we test we should be recovered and in a non-fatigued state,” said Jones. “There is a learning period to each test and you can have anxiety, especially if you haven’t done it before. [Because of testing anxiety,] a novice athlete can have vast changes in heart rate zones, power zones and even physiology, because hormonal changes affect how your heart pumps.”

You’ll also see changes in your zones as you get more fit—which is why you have to retest periodically. Kowal added that using multiple metrics to develop training zones gives you additional feedback tools you can turn to once you have training zones are established. If, for instance, you realize your heart rate versus RPE seem off, you can adjust your training zones for future workouts.

Establishing Training Zones

As we noted above, there are various definitions for the number of training zones and for the threshold effort used to establish those training zones. The most common calculation is to use five training zones (with the hardest or fifth training zones sometimes broken down into additional sub-zones).

What is threshold? There are also different threshold points, and different coaches use those points differently. Lactate threshold heart rate is the intensity at which lactate begins to accumulate in your blood. Functional threshold power, used on the bike, is essentially the power or effort you can sustain for about an all-out hour. These are not the same thing, but for many athletes they require about the same effort level and typically fall around the line between zone four and zone five.

You can then use a calculation to extrapolate from your threshold (top of zone four) to figure out your other zones.

Run Zones

Zone 1: Less than 85% of lactate threshold heart rate (LTHR)
Zone 2: 85-89% of LTHR
Zone 3: 90-94% of LTHR
Zone 4: 95% to 99% of LTHR
Zone 5a: 100% to 102% of LTHR
Zone 5b: 103% to 106% of LTHR
Zone 5c: More than 106% of LTHR

Bike Zones

Zone 1: Less than 81% of LTHR
Zone 2: 81% to 89% of LTHR
Zone 3: 90% to 93% of LTHR
Zone 4: 94% to 99% of LTHR
Zone 5a: 100% to 102% of LTHR
Zone 5b: 103% to 106% of LTHR
Zone 5c: More than 106% of LTHR

You can also use this chart for establishing heart rate zones based off max heart rate. However, while these are the common zone calculations used for a five zone system based on lactate threshold, there are other systems—such as a two-threshold seven zone system. Additionally, your specific zones should correspond with the prescribed workouts you’re doing.

Whatever system you use, the point is to know that Zone 1 is the easiest, Zone 2 is a steady effort, Zone 3 is a tempo (think 70.3 effort), Zone 4 is what you can do all-out for an extended period of time, and Zone 5 and above is very very hard. In order to figure out what each of those zones mean for you, you need to do test to establish where your threshold is and what you can sustain right now.

Swim Test to Establish Training Zones

When it comes to swim testing, you have a few options. One would be to do a time trial, swimming 1,000 yards and taking your pace and average heart rate from that effort to establish your threshold.

Jones also recommended a step test of five 200s. As you get quicker, you take your heart rate at the end of each 200 to determine an average heart rate.

Bike Test to Establish Training Zones

A common test to establish training zones on the bike is a FTP (functional threshold power) test. For this test, you warm up, do 5 minutes hard, recover and then do a 20-minute all-out effort. Use your power and heart rate for that 20-minute effort to establish a threshold. Jones adds that it can also be based on a climb, where you ride until you can’t anymore and you can then find your maximum heart rate, which can also be equated to feel.

If you are on a trainer and want to do a test based on power or watts, Jones recommends a maximal test done in minute increments. Using a ramp test like those built into online cycling programs like Sufferfest does the math for you and leads you along the incremental increases—so you don’t have to think bout it. This can be done indoors and you can then establish your zones based off your performance in the ramp test. “Power wins out in everything when it comes to a maximal test,” Jones said.

Run Test to Establish Training Zones

You have some options for running, as well. You can do a test similar to the FTP test, where you use a 30-minute all-out effort and look at your heart rate across the final 20 minutes to establish your threshold. Do the 30 minutes as a race-type effort, all-out, but press lap after the first ten minutes in order to get your heart rate across the final two-thirds of the test (because heart rate can lag).

Additionally, Jones said you can use the recorded date from a 5K or 10K time trial. “With experience, a 10K time trial will give you heart rate zones and 70-75 percent of your max heart rate will be a close estimation of an aerobic run for you,” he adds.

Data Collection is Key for Correct Training Zones

The more data you can get, the more accurate your training zones will be. Not only do you want to practice testing as you get more comfortable with it, but you also want to re-test every few months in order to collect new data as your fitness progresses.

“Retesting and testing continues to build up an athletic picture,” said Jones. “Your first test should be perhaps more rated on RPE and as you get better and better at testing, then you can use heart rate a little bit more closely.” And then you can add power in as well.

How to Establish Triathlon Training Zones