HRM 200 spikes during activity

I had sort of the opposite problem: not spikes up but down. When biking with an Edge 1040 Solar it sometimes would record 95 BPM for a second or two, then going back up to my actual heart rate (say 130 to 150). This made the graphs look like this.

My suspicion was that this is a Bluetooth issue, because it did not happen when running with a Fenix 6. There the connection is the "old" ANT+ method, whereas on the Edge 1040 solar I used the new encrypted connection/pairing method at first. Switching to the old unencrypted method seems to have helped on the Edge too, but I need more testing.

In the meantime Garmin email support also offered already to replace my unit, which I might do eventually within the guarantee period... But I just saw a post here that there is a new firmware update too which I do not have yet, so I will try that some day.

What firmware are you on, zgrega? And are you using the old or new/encrypted connection method / with what watch or other device?

Hi 9913112,

just to confirm your point

9913112 said:

this is a Bluetooth issue, because it did not happen when running with a Fenix 6. There the connection is the "old" ANT+ method, whereas on the Edge 1040 solar I used the new encrypted connection/pairing method at first.

This is very likely, at least in my experience from a few years back. I had an external HRM from another company, that used BT Low Energy aka Smart to connect. I had similar "spikes down" which were connection problems. I could even see, WHEN it happend (live), it was after every notification for a completed lap/km, that for 2-3 seconds connection was lost. And it was a Forerunner 245 back then.
Changing to a Garmin HRM and using ANT+ solved the problem permanently for me.
Never had connection issues after that - in my experience ANT+ is super solid and reliable.

BTW, slightly off topic: I don't get the move with "secure encrypted" BT-Connection for sensors. What is the use of that, anyway? Those sensors are not communication through the internet, but have a limited range of max. 10 meters, if at all.
So, I really don't give a *****, if somebody that is that close to me during all my workouts or events will be able to read my "unencrypted" HR, cadence and, god beware, my wattage that I produce on my bike

Grumpy from dawn till dusk said:

I don't get the move with "secure encrypted" BT-Connection for sensors.

In brief: EU requirements.

In details: The Begining of the End for ANT+ Wireless | DC Rainmaker

The core reason for this change is the European Union’s Radio Equipment Directive (simply called EU RED), which will ultimately take full effect next summer (it’s currently in a transitional phase). That directive covers a flotilla of different areas, but one of the most applicable pieces is that it requires authentication and encryption for wireless communications of personal information. Or, at the very least, it requires manufacturers to make you aware when data is being transmitted without such protections.

Thanks for the link - did not know that.
Generally I think the regulations goals are ok, but specifically for sports sensors with a range of maybe 5 meters it is overkill. Especially considering what DCR wrote - that there are nearly no standardized sports profiles for BT LE , while ANT+ has those.

But good thing is, that it will continue to work for a couple of years.