Activity uses wrist HR when HRM strap connection drops

Set power mode to Jacket mode for this activity and it will turn off your wrist HR automatically.

Thank you for the recommendation. I checked settings for the respective app on the FR945, but there are only general options like uninstalling the app from the watch. Nothing like power mode in sight.

OK, my answer was based on my experience with Fenix 7 where such profile exists and you can assign different power modes to different actifities.

Instead of disable wrist HR  (along with complete loss of heart rate data when HRM is disconnected),

try put on the watch on the other hand during training.

I did this when the fr55’s BT/ANT+ communication radius sharply decreased.

HRM PRO uses ANT+ to communication with watch, and only then transmit all data.
If connection type will be BT, only HR will be transmitted from the strap to the watch.

This is not about this. BT and ANT+ use the same radio module. So it makes no sense to change the ANT protocol to BT.

I suggest putting the watch on the other arm rather than changing the HRM communication protocol, so a your note irrelevant.

Thanks it's a good point too, I keep it on my right side which I use more for arm swing during skating so it has in general the closer proximity to the chest belt transmitter.

I am guessing that it is due to upsetting the location/tension or something of the strap... cuz I get notice of my strap connecting to watch when it is in the other room sometimes through walls/etc.  My arm when running is behind my back for moments at a time every arm swing... seems strange you would see this just having it behind your back?   Or in the case of my coros arm band HR... it is on my other bicep from watch... so nearly through body all the time to get to my watch ?  

For instance a month or so back someone had connection issues... turns out it was fixed by tightening strap after he lost some weight.  In my case I see that cuz i'm pretty low body fat and skinnyish... so hard to get tightness quick right.  So sometimes when I get a drink from bottle while on Tread or on Trainer it will drop connection for 10-30seconds.  Isn't cuz of proximity... just cuz electrodes probably lose connection to chest for a second and causes a hickup in connection.