I have an issue since 6 months with my Garmin and I can't find anybody complaining with it on any sources on internet.
Using Garmin Fenix 5X with HRM run 4 (and also tried a HRM Tri), when doing interval / tempo trainings, I have spikes of HR.
Running on a track and doing series of 400m or 800m or so, I do series at around 180-185bpm of real HR and have spikes up to 225bpm!
Sometimes it happens at the beginning of each interval. Jumping from 140 to 210 and then stabilize at the correct 180. Sometimes it happens after 1-2mn of effort and stay incorrect until the end of the serie. Sometimes I have up-down-up-down from 180-210-180-210 during the same serie. And I also experimented big drops when doing high intensity for longer period (during race and race simulation). I'll have the reading dropping at 110 for 1 minute or 2 and go back to 180.
It's happening during ALL my interval trainings which is extremely irritating.
I can't trust the device anymore, and get wrong VO2max estimation, wrong recovery time, wrong average HR, wrong lactate threshold estimation, wrong training effect, wrong training status ....
Of course, I went through all the debugging process before posting a desperate message like this :)
I started with replacing the battery of the HRM 4, and then buying a new HRM Tri. I got the same issues => it's not coming from the chest strap, so it must be the watch.
I reset the watch to factory settings => same I contacted Garmin support and change the watch => same !!
Different watch, different chest strap, and nobody complain about ... I can't be the only one having this problem, it can't be?
I am attaching 2 examples with a 5KM run showing 10mn of completely innacurrate data for a workout of 20mn!! And a beautiful interval training showing the HR of a new born at each acceleration.
if I didn't know myself very well, I would stop running and run to the nearest hospital.
Just one addition, it never happened before April this year, I been using the watch for 1 year, and a previous Garmin Forerunner watch and never get the issue before. There was no upgrade of firmware at that time and I tested all configurations anyway (with factory reset, and all firmwares since 8, it's now 11 and happens all the time.
I never got a correct interval training reading since April.
