How are training zones calculated?

There are two ways to turn your heart rate into training zones — heart rate reserve and heart rate max. They set the thresholds between your zones differently, so the right choice depends on what you want your points to measure.

Two ways to build your zones

Heart rate max sets your zones as a straight percentage of your highest heart rate, so it needs only that one number — known in the research as the percentage of maximal heart rate (%HRmax) method[1]. Heart rate reserve uses your heart's available range — how much your rate can climb above rest — so it factors in your resting rate too; this is the Karvonen method, named for the physiologist who introduced it[2]. Two people who share a maximum but rest at different rates get identical zones under heart rate max and different ones under heart rate reserve.

Where the thresholds sit

The methods differ in where they place the thresholds between zones. Because heart rate reserve counts upward from your resting rate, every threshold shifts up and each zone requires a larger real effort to reach. Heart rate max measures from zero, so the same zone thresholds fall lower and a gentler heart rate already counts. For example, a heart rate that qualifies as Zone 1 under the heart rate max method might fall below the Zone 1 threshold under heart rate reserve.

Heart rate reserve suits training hard

Heart rate reserve places Zone 1 at roughly 50% of your reserve, the minimum intensity research links to improving cardiorespiratory fitness and raising your VO2 max[3]. With the bar that high, incidental movement — walking up some stairs, carrying shopping, a quick walk between meetings — stays below it, and reaching the threshold takes deliberate effort. This is the default in ZonePoints, and the recommended choice if you are already active and want only focused training to count toward your points.

Heart rate max suits staying active

A lower entry point means lighter activity crosses into Zone 1. If your aim is to move more and keep the habit going, that is the idea: a brisk walk, light housework, or an easy ride registers as time in zone and earns points. Choose it if you like to stay active and want everyday low-intensity movement to count.

Your sessions are timed automatically

Whichever you pick, ZonePoints needs no manual start or stop, and has no timers to configure. Training time automatically begins the moment you cross into Zone 1 and pauses when you drop below it. Your sessions time themselves completely hands-free, so your weekly total reflects only the time you spend inside the zones you have set — not warm-ups, rest periods, or movement below the threshold.

References

1. Methods of Prescribing Relative Exercise Intensity: Physiological and Practical Considerations
   Mann, T., Lamberts, R. P., & Lambert, M. I. (2013).
   Sports Medicine, 43(7), 613–625
2. The Effects of Training on Heart Rate; a Longitudinal Study
   Karvonen, M. J., Kentala, E., & Mustala, O. (1957).
   Annales Medicinae Experimentalis et Biologiae Fenniae, 35, 307–315
3. VO2 Reserve and the Minimal Intensity for Improving Cardiorespiratory Fitness
   Swain, D. P., & Franklin, B. A. (2002).
   Medicine & Science in Sports & Exercise, 34(1), 152–157