HRM-Pro Plus initial spike when running

Has it always been doing this with the HRM-PRO Plus or did it just start?

I don't have that with my HRM-PRO plus 

Maybe try the reverse polarity reset and also un-pair and re-pair with the device. There is a description of that in this post

forums.garmin.com/.../garmin-hrm-dual-not-working

I have same issue, now with HRM-Pro Plus but similar situation on HRM-PRO.
ECG gel works a little but is not perfect and doesn't solve it completely.
From my observation, this spike is always when your strap is not transmitting respiratory.
Some people says that making whole strap wet solving problem but never tried it.
From my observation issue is much worse during Winter, during Summer almost doesn't exist.

I'm using now Fenix 7 but had same situation with Fenix 6 and HRM-PRO.

Today it was like this:

But yesterday it was fine:

Mine is ok starting out. (HRM Pro plus) however about 6k into my run my pace spikes no reason, running at steady pace. This happens after 6k… then my heart rate drops (lost connection and goes to 0, which causes my pace to go to 0, even thou I’m still running. Taking Watch off didn’t help. 

I’m using a Garmin 965 with beta firmware. Wonder if the spike has something to do with the beta. Possibly your running beta on your watch?

interesting in that I paired my hrm pro plus with my Apple Watch and no issues with the spike nor pace going to 0… could be an ant issue on Watch 

Thanks for the tips, have just tried the reverse polarity reset so will see how that goes tomorrow. Also not running any beta software, standard 15.77 on Epix Pro.

Seems like my HRM's trolling me as tonight I hit Z4 within minutes of my slowest run this month. As with Adam-1972, no respiration data when the HR is spiking; once the spiking stops, respiration starts. No idea how or why those two seem to be affected; surely if my HRM thinks I'm hammering out a Z4 run, it would also think my respiration rate would be greatly elevated? 

Question to Adam-1972 - where there was no spike, had you previously used your HRM for an activity earlier that day?

Will try soaking the whole thing tomorrow before my run, I wonder if it's already got perspiration from an earlier activity (that day), it might resolve the issue (and would suggest it's related to strap dryness / conductivity).

mrw_y2k said:

Question to Adam-1972 - where there was no spike, had you previously used your HRM for an activity earlier that day?

Yes, but it is my routine to do 5 - 10 minutes worm-up before I go for run.
Today I will soak my strap to and check the result (to be honest never tried it earlier).

Just try to run with whole strap wet and no changes.

Next time will try hard reset sensor, but don't have to much hope into it, especially that I have same situation with HRM-PRO strap.

This is promising......

I did the reset sensor / reverse battery fix last night and removed and re-added HRM to watch as a new sensor, then today soaked the strap 5 mins before run and sat it on a towel while I was getting ready.

I have done some runs this month the same day I've done a couple of hours on the bike (turbo) so HRM was still wet with sweat.

On these occasions, the initial spike has been less. Will test some more, but hoping the combination of sensor / reverse battery fix, and ensuring the whole HRM is fully wet before running, will resolve the issue.


   

mrw_y2k said:

ensuring the whole HRM is fully wet before running

This is the long term solution. I’ve always done this before every activity except swimming 

Interesting, I will try to repeat this.
It is little inconvenient when outside is cold.