The five-zone model, without pretending it is exact
Wellness Project's provider-neutral workout view can use five bands anchored to your maximum heart rate: about 50-60%, 60-70%, 70-80%, 80-90%, and 90-100%. That framework is useful for comparing intensity within your own history, but it is not a universal law. Some providers use threshold heart rate, heart-rate reserve, custom zones, or their own labels, so two apps can put the same 145 bpm in different zones.
What heart-rate zone should you exercise in?
There is no single best zone for every workout. Easy endurance and recovery sessions usually belong in lower personalized zones where conversation is comfortable. Tempo, threshold, interval, and race-specific work intentionally move higher. The useful question is whether the zone matches the purpose of the session, not whether you spent the most time in the hardest color.
Zones work better with the rest of the workout
Time in zone becomes more useful when it sits beside duration, pace or speed, distance, perceived effort, Training Load, heart-rate recovery, HRV, and sleep. A high-zone interval day and a long low-zone ride can create very different stress even if both look like successful cardio sessions.
Turn heart-rate zones into workout history.
Import supported workouts into Wellness Project to see heart-rate detail in context with Training Load, recovery, sleep, running, cycling, strength, and the rest of your health data.
