What can cause a SO erratic heart rate value from the same HRM Pro+

The all-day HR data comes from the wrist optical sensor of your watch, not from the HRM Pro, unless you have connected the HRM to the watch too, and started an activity on the watch. Besides that, the all-day HR graph shows the HR averaged to 2 minutes intervals, hence any short high peaks of HR will be smoothed out.

Yesterday, I wore my HRM Pro+ all day while working.

It was connected to my watch and to my IPhone8.

My watch always recognize my HRM Pro+ and connect it from the moment I wear it.

There is a buzz sound and vibration when it occurs.

IOS is up to date.

Started my Standard FTP test in the afternoon.

Same thing happened when I did a second ride as a Standard FTP Test and I got the same results.

30-60bpm less on the Health Stats/Heart rate in Garmin Connect.

As for the "smoothed out", even if there is a 2min delay, over a 55min training, where there is a 5min and 20min at 160bpm, this is over a 15 and more readings so it should have shown many peaks, that would have been smoothed out and level at 157 and 160bpm during the training time.

If the HRM would be the problem, it wouldn't have done differently in Zwift and in Garmin.

This is yesterday where I wore my HRM all day.

ManSurfingOnLifeBuoy said:

Yesterday, I wore my HRM Pro+ all day while working.

It was connected to my watch and to my IPhone8.

The watch does not use the external HRM unless you explicitely start an activity on the watch.

... you can read more details about it in the HRM-Pro FAQ. Besides others, it tells:

HRM-Pro and Pro Plus: Top FAQs About the Activity Tracking Feature | Garmin Customer Support

When not recording an activity with the watch, if you wear the watch and strap at the same time, the all-day heart rate data in your Garmin Connect account comes from the watch.

I read my question and explanation again to make sure I was clear enough.

I think that your answer is besides the point.

To be frank, who cares about when the strap is wore and that the watch will wait until I'm in an activity to be connected.

I put it on and my watch vibrated and I saw a brief message to tell me that it was connected.

I wasn't in an activity but so many things are weird when we try to understand a problem.

It was a test to see if that would change the outcome, which is that I still don't get the right data and that I'm still getting data that tells me I will have to go over 210bpm to be able to get to 160bpm in Garmin's graphs.

That is my point.

2 times, I was IN an activity, Zwift, wearing my HRM Pro+, well humidified, connected to Garmin via their collaboration connection.

The right data was sent by/from Zwift to Garmin because Garmin can display that exact same data for the heart rate in the activity report.

Garmin Connect should use those data in the tables and display the graph for health stats/heart rate showing the same data.

So my question is, where do I go to check the right boxes to make sure all HR data are the same ?

Because right now, my VO2Max is 43, my training status is Strained, my HRV Status is low at 36ms, my PulseOx/SPO2 is 94%, my resting heart rate is 55, my body battery is 48, my training readiness is 65.

All that because my data don't take into account the real change in HR.

If my watch doesn't pickup my Heart Rate Monitor, there should be a place in Garmin Connect where I can tell GC to prioritize my HRM Pro+ instead of my wrist HRM.

So when there is a conflict, my HRM will bypass my wrist HR.

Or just having the Zwift data ton replace the Garmin Data when it doesn't make sense.

I am just trying to explain you how it works, and how you can achieve what you are looking for. As an ordinary user, I have no power to change the way Garmin designed it, but personally I am easily able to work around it. You are free to use the friendly advice, or reject it. If you want that Garmin changes the way it works, then I recommend you to contact them directly either through their support lines, or submit your request through the form Share Ideas | Garmin 

Thanks Trux.

Nothing against you but I need a solution. Not excuses.

I connected my watch, GC with Zwift for a year.

This means that for a year, I made decisions about how I can improve my health based on incorrect data.

I was probably more in shape than I thought but also focusing on stuf that I didn't have to.

I read many posts, my Fenix 5X documentation from one page to the last and I never bumped into any of the information that you say.

So, I'm pretty frustrated right now.

Yes I will certainly send a request but this should be explained somewhere in the Garmin documents or from Zwift (which collaborate with GC) that Garmin watches don't collect HR data from other App connections, other than displaying them, and therefore, it uses only the HR from the wrist if you don't activate an activity.

So, it would have been explained while connecting Zwift (or any other app) at that connection moment, I would have known and started a year ago to record my HRM Pro+ data. Because now, those data are not used when my watch tell me that I do too much Low Aerobic training.

But from what I read, at least you tried.

For me, this means that when I will do a ride or any workouts, from now on, I will have to engage my watch as an Indoor Bike, start and stop at the right moment to make sure that Garmin record the real heart rate, which is stupide because it will be by Ant+ with my watch and with Bluetooth with my AppleTV 4K for the same thing.

I understand that you cannot do anything but maybe somebody else had the same issue and found a solution better than mine.

I just went back to a Zwift Training I did sept 2nd.

I had my Fenix 5X.

I always thought that data were good, and they are not.

24bpm difference.

So, anybody who has a better solution than this, is welcome to share.

I'll do a test ride tonight and keep you posted.

ManSurfingOnLifeBuoy said:

Nothing against you but I need a solution. Not excuses.

I gave you one already - connect the HRM-pro to your watch (you did) and start the activity on the watch (you did not, as far as you described your case).

Hi Trux.

Just got another reading on the subject.

Many others are frustrated about discrepancy in data.

https://forums.garmin.com/outdoor-recreation/outdoor-recreation/f/fenix-6-series/254214/training-effect-calculation

In my case, it is still incomprehension.

Here, on sept 17, the day before I received my new Epix Gen 2, my Fenix 5X recorded a peak at 227bpm.

Surprisingly, I'm still alive.

But GC doesn't seem to take into account that 227bpm value for the yearly graph, which is 164bpm.

So what should I think of it ?

As per the test, wearing the strap and starting an activity.

I did yesterday.

They look quite the same.

So this means that I got to expect a 60bpm difference between my wrist HR and my HRM Pro+ if I don't start an activity.

I'm still disillusioned over my 1K$ watch though.

Here is another metric around that same activity/event yesterday.

As you can see, Oct 12 (lowest in the list) is the Zwift workout.

It gives me a VO2 Max at 3.3.

The third one, (12 oct at the top) gave me a VO2 Max at 4.4

Both had a wrist watch Epix Gen 2 and a HRM Pro+ connected to them.

Both were on Garmin connection (data collected only on Garmin).

So, which one is the good one ?