Random Heart Rate Alerts


I recently bought a used Fenix 5. I then performed a full reset.

Then I attempted to set an alert for when I hit the lower threshold of Zone 3 and then again for when I hit the upper threshold of Zone 3.

I tried to do it in the following way:

  1. Hold MENU.
  2. Select Settings > Activities & Apps.
  3. Select Run 
  4. Select the Run settings.
  5. Select Alerts.
  6. Select Add New
  7. Select Heart Rate
  8. On the HIGH ALERT screen select Aerobic (Z3) 121-138bpm
  9. On the LOW ALERT screen select Aerobic (Z3) 121-138bpm
  10. The screen now shows 'Heart rate 121 - 138 bpmI thought that was set and I was ready to go.

However, when I went for a run, I kept getting alerts at random heart rates such as 88 bpm, 96 bpm, 111 bpm, 118 bpm 119 bpm etc.

And I'm pretty sure that it didn't go off when I reached 121 bpm and then when I went over 138 bpm.

Does anybody have any idea what is going on? I'm pretty sure that something might be activated to in the watch, but have no clue as to what.