ManSurfingOnLifeBuoy said:

.zip files cannot be sent via this forum.

If you zip the file or simply change the file extension to ".zip," it is possible.

• In a reply post Insert >> Image/video/file >> click Upload >> browse for file >> OK.
• If you're still unable to do so, you can upload the fit file to a reputable file sharing service, such as OneDrive, Google Drive, Dropbox, make the file public, then paste a link to the file in your post.

ManSurfingOnLifeBuoy said:

If you need the files for the second time I did the FTP test, I can send you the files too.

I just created the Fit file from Zwift.

FTP Test In London

2023-10-09

I Exported a zip file from the Heart Rate section in Garmin Connect/Health Stats/Heart Rate.

Preferably send the FIT files for the last activity that you shared, the one that I replied to, where you posted the graphs showing the heartrate data from both Zwift and your watch (max bpm 122/124).

For the Zwift FIT file, preferably post the file that is on your computer where you run the Zwift app (not a FIT file downloaded from Zwift's website).

For the Garmin file, post the activity's FIT file, using the Export Original option on the Garmin Connect website (or get the file directly from the Activities folder of your watch).

I want to compare the 2 files because the activity's heartrate data appears to be different for some reason in the graphs you posted. (I'm not looking at the "all day" HR data).

First try.

Garmin Heart Rate Export.

Which correspond to my Heart Rate recorded by my watch (according to trux) during the FTP_Test_London_2023-10-09

Garmin_HeartRateExport_2023-10-09.zip

Second try.

This file is the Zwift Fit file zipped.

Zwift_FTP_Test_London_2023-10-09-16-39-45

Zwift_FTP_Test_London_2023-10-09-16-39-45.zip

ManSurfingOnLifeBuoy said:

First try.

Garmin Heart Rate Export.

Which correspond to my Heart Rate recorded by my watch (according to trux) during the FTP_Test_London_2023-10-09

Hi, this isn't an activity FIT file. We're looking for the activity you said you did on Zwift and also recorded on your Garmin watch as you described earlier. Go to that activity in Garmin Connect website that was recorded by your watch, click the gear icon at the upper right, select Export Original, and post that file.

Then post the Zwift FIT file for that same activity (if you haven't already). It will be in your Documents\Zwift\Activities folder on the computer where you run Zwift (on a Windows PC at least).

ManSurfingOnLifeBuoy said:

Second try.

This file is the Zwift Fit file zipped.

Zwift_FTP_Test_London_2023-10-09-16-39-45

Hi, also this Zwift FIT file appears to be from a different activity. Looking for the FIT files from the specific activity for which you posted all this:

ManSurfingOnLifeBuoy said:

Yes.

Here are the graphs.

First is from Zwift.

Second is from Garmin with watch Epix & HRM Pro+.

They're should be, at least, the same HR, which is not.

Zwift don't calculate metrics when it has access to devices.

So without a HRM, yes it will extrapolate but when HRM, powermeter, cadence is present, it just take the data from them.

Which is the case here with a Wahoo Kickr V5 Trainer and a HRM Pro+.

Then post the Zwift FIT file for that same activity (if you haven't already). It will be in your Documents\Zwift\Activities folder on the computer where you run Zwift (on a Windows PC at least).

I run Zwift from an Apple TV 4K 128Gb. Pretty hard to find any log or fit file from that.

So I won't be able to send you that file anyway.

Cannot get it from Zwift or any other place.

Can you explain why the files I sent you are not at the same HR ?

For those two first file, that is from my first FTP Test, even if I didn't start an activity (which I never have during the last year), my HRM Pro+ was connected to my watch during the whole Zwift workout and was communicating with my watch by ANT+. And it was communicating with Zwift by the same HRM Pro+ by Bluetooth.

I'm looking for a way, a setting, to make sure, that what ever I do with my watch, if I wear my HRM, that should bypass the wrist HRM.

Is that possible ?

That way, even if it is a All day HRM on my wrist, the HRM Pro+ should bypass the wrist HRM if I'm wearing it.

If not, what's the point.

I will get back to you with those files because it is a lot of work just to get them.

ManSurfingOnLifeBuoy said:

I run Zwift from an Apple TV 4K 128Gb. Pretty hard to find any log or fit file from that.

So I won't be able to send you that file anyway.

Ok since you use Apple TV, then the FIT file you download from the Zwift website will have to do.

So, again, for that second Zwift activity (not the FTP one) that you recorded on your watch, please post:

1) FIT file downloaded from Zwift website

2) FIT file downloaded from Garmin Connect (the one that was recorded by the *watch*, not the one that comes in from Zwift).

These 2 FIT files should have the same heartrate data since you used the same HRM for both, but since your screenshots seems to show that they are different, we should examine them to find out if/why the HR data doesn't match.

Kyle J said:

These 2 FIT files should have the same heartrate data since you used the same HRM for both

Not necessarily identical, because each of the sides may use a different sampling rate. For example if the watch uses the default "smart recording", the logging rate will be variable and can be at times considerably longer than 1s. I do not know what sampling/recording rate Zwift uses, but if it differs, then the data and the graphs would not be perfectly identical.

Besides that, one or the other side may use different algorithms for calculating the HR from the beat-to-beat data of the HRM. They may use a small floating average window, and filtering functions to eliminate random signal noise, and these algorithms may differ on both sides. 

Hi trux yes of course I don't mean 100% identical, but they should be substantially similar. In the later screenshots the OP posted for their "second activity", it appears like the two are not in agreement (trends don't match), which is why I think we should get both FIT files (Zwift & device) and compare the HR data. An actual mismatch would be really strange though, so until someone sees the FIT files I'm not sure it's not simply a case of user mix-up somewhere. (I agree it's all somewhat tangent to the OP topic regarding all-day HR, but good idea to at least confirm their HRM connection is working okay. All the points you made earlier still valid of course.)

My understanding is that HRM devices (and other ANT+/BLE sensors) transmit the final HR bpm values directly, without any processing required by the receiving device. (Read that here somewhere..., think it was in a post explaining the error detection protocol for the data transmission, explaining that if the values are "incorrect", it happened in the device before transmission.) So all receivers are listening on the same data stream (allbeit at potentially different polling rates).