I am not sure how many people do actual use a custom data screen that shows time in HR zones. Out of curiosity I configured one of my custom running sport profiles to have it and have noticed that it is actually not working correctly.
Here you can see me in Zone 2. Note that it shows 17 min 33 sec in Zone 2, no time spent in the zone above (Zone 3), and 13 min 08 sec spent in Zone 1. The total elapsed time is just over one hour.
[image: 1769132382353-pxl_20260123_000237944.mp-edit.jpg]
Here, 30 seconds later I waited for the HR to drop to Zone 1. What we can see is that the time in Zone 1 is now 42min 23 seconds as it should be. However the time in Zone 2 is now shown as zero. The time in the zone below, whatever that is, is 13 min 08 sec.
[image: 1769132394894-pxl_20260123_000310190.mp-edit.jpg]
Obviously it doesn’t show correct time in zones above and below the current current zone. In fact, from what I observed, the time in zone above was always zero throughout the run, regardless of what zone I was in. Also the time in the zone below was always the same 13’08.