Running Intensity Zones: Speed, Heart Rate Zone, and Power

running intensity zones

GPS watches from brands like Garmin, Polar, Suunto, and Coros have popularized training zones. These manufacturers categorize intensity into five running intensity zones, ranging from low (typically indicated in blue) to high (marked in red). Let’s explore what these zones signify and how they are applied in RunMotion Coach.

The definition of Intensity Zone

The intensity zone scale utilized by connected devices typically comprises five levels. It’s a choice influenced by the endurance athletes who use these watches and rarely surpass their Maximum Aerobic Speed (MAS).

Simplified, MAS represents the highest speed an individual can sustain over a 6-minute race. Athletes participating in distances ranging from 5 km to marathons, and even ultra-marathons, rarely exceed this pace. The exception might be at the start and during the final sprint.

Each GPS watch brand may define its zones differently, leading to minor variations in the parameters that delineate each zone.

The limits of each zone can be characterized by speed, heart rate, or power, with correspondences established between percentages of MAS, Heart Rate Reserve (HRR), and power output.

However, when dealing with percentages of maximum heart rate (HRMax), precision diminishes, and direct equivalence is lost. This is because, at rest—implying zero speed—your heart rate does not drop to zero (which would indeed be alarming 😅) but typically ranges between 40 and 80 beats per minute, reflecting your resting heart rate. Therefore, it is more accurate to refer to Heart Rate Reserve when discussing heart rate-related intensity zones.

The 5 Intensity Zones

Garmin categorizes its intensity zones by default as follows: Zone 1 ranges from 50% to 60%, Zone 2 from 60% to 70%, Zone 3 from 70% to 80%, Zone 4 from 80% to 90%, and Zone 5 from 90% to 100% of the maximum heart rate (HRMax). This approach is effective for general fitness but can be further tailored for running to align more closely with physiological metrics.

Our definition of the 5 zones is based on four key physiological data points: VO2 Max, anaerobic threshold, aerobic threshold, and high fundamental endurance.

These parameters can be accurately measured during a VO2max test conducted by a physiologist. It’s important to note that a test performed by a cardiologist might not provide the necessary insights to define these zones accurately. Indeed, it primarily assesses the heart’s response to exertion without measuring oxygen consumption.

This methodology results in five zones that have similar ranges to Garmin’s, but they are often more closely aligned with the individual’s physiological characteristics.

In percentage of MAS (Maximal Aerobic Speed)

You can use our MAS table to determine the paces corresponding to each training zone.

Zone% MAS (varies among runners)Perceived EffortCompetition pace for most runners (this mostly depends on the race duration)
VO2 Max – MAS
588-100%High intensity, sustainable only for a short duration. Breathing is rapid, and speaking is no longer really possible.
5 & 10km
Anaerobic Threshold
479-88%Medium intensity, sustainable between 1 and 2 hours. Breathing is quite rapid, and speaking is difficult.
Between the aerobic threshold and the anaerobic threshold, we divide this range into 2 equal zones
370-79%Medium intensity, sustainable between 2 and 5 hours. Breathing is at a medium pace.Marathon
Aerobic Threshold
260-70%Moderate intensity, sustainable for several hours. It is fairly easy to speak.
Long trail – Active Endurance
High Fundamental Endurance
10-60%Low intensity, sustainable for many hours. Breathing is quite slow. It is easy to speak.
Ultra trail – Fundamental Endurance

Our practical advice

For less experienced runners, Zone 1 might seem unusually slow. In such cases, it’s acceptable to shift into Zone 2 if Zone 1 feels too slow. Fundamental endurance can also be effectively developed through brisk walking, hiking, or cycling.

The Zone 1 that RunMotion Coach defines often matches Garmin’s default Zones 1 and 2, with Zone 2 capped at 70% of maximum heart rate. We advise sticking to Garmin’s Zones 1 or 2 for fundamental endurance activities, where speaking should remain effortless. If you enter Garmin’s default Zone 3, you’re going too fast.

RunMotion Coach’s Zone 2, aimed at active endurance, corresponds to the higher end of Garmin’s Zone 2 and, for certain individuals, may overlap with Zone 3.  If you enter Garmin’s default Zone 4, you’re going too fast.

The specifications for Zones 3, 4, and 5 show considerable similarity between RunMotion Coach and Garmin.

Within the RunMotion Coach app, your personalized training paces are derived from your historical race outcomes and related performance forecasts. This includes MAS, endurance index, and projected times for various distances.

Running intensity zones, speed, and heart rate are established using our mathematical model.

Adapting these zones in your RunMotion Coach application

If you’ve completed a physiological test that accurately identified your fundamental endurance, aerobic and anaerobic thresholds, and MAS, you can input these figures into the app by navigating to “My Profile -> Export my training plan -> Define your heart rate zones.”

By incorporating these precise data into the RunMotion Coach app, you will adjust your training paces accordingly, achieving a more precise correlation with your heart rate data.

For those who haven’t undergone a physiological assessment—which is the case for most of us—we suggest maintaining your current paces unchanged.

However, if you notice that your profile either overestimates or underestimates your MAS—perhaps due to recent significant progress, or because your race outcomes might have improved if you had been using RunMotion Coach 😉—you can adjust this data under “Define your heart rate zones“.

Updating your MAS will immediately reflect in our database. (with instant display in My Profile on Android devices, though there might be a slight delay on iPhones, in which case, recalculate your plan). This adjustment is also applicable to fundamental endurance; should you wish to modify it, simply follow the same procedure.

You should only complete the table with the data you intend to update.

If you absolutely want to enter the running intensity zones of your GPS watch

If you haven’t undergone a physiological test and still wish to input the intensity zones from your GPS watch into the RunMotion Coach, you’re free to do so in the provided table. However, keep in mind that these figures may not be more precise than the predictions made by the RunMotion Coach mathematical model.

These zones can be useful for regulating your effort but remember, they are merely numerical representations. Nothing can substitute the intuitive feeling you develop as a runner 😉 Variables such as the day’s weather conditions, the terrain, and your physical state can all influence your pace, heart rate, and power.

It’s also crucial to remember that the accuracy of GPS and heart rate monitors is limited. At their best, they are accurate to within 1%, and often, they are less reliable than that. Optical wrist sensors for heart rate, in particular, can vary significantly in accuracy. For instance, due to my thin wrists, I’ve found that no watch has provided me with consistent readings. Arm or chest sensors tend to offer more reliable measurements.

For those using power sensors like Stryd, RunMotion Coach also provides conversions between speed and power, enhancing your training insights.

With all this information in hand, all that remains is to wish you a productive and enjoyable training session!