Garmin Fit File importing to ZP with incorrect date

I’ll try keep this short -
When I dual record and import the created .fit file into ZP the graphs no longer align. There is a missalignement of, not a few seconds, 482,537 hrs between them. Which when calcualted out equals 55 years.
The entry then gets entered into my profile “Analysis” page under the creation date Thurs 1 January 1970 00:00 (55years ago)
All my .fit files are now being entered under this date. Been like this for at least a month now.

I’ve checked the .fit files on various online fit file fixer websites and all the times and dates are recorded correctly and when I search the entire file contents for any mention of the number 1970 it only shows up twice, both times within a large accumualted_power number.

I’m baffalled as to where this 1970 date is coming from. If I download an older .fit file from my Garmin account - say one from October - it loads into ZP with the correct date. But more recent files from my Garmin account are uploading with this 1970 date.

Anyone any ideas?

https://runalyze.com/tool/fit-viewer/c6dfc2a78b9f366fa74872c2db4c369b/view

Link to one of the files.

00:00 on 1 Jan 1970 is the Unix Epoch, a date that can be observed when a Unix/Linux system has a date of zero seconds from the beginning of time.

I’m not sure what’s going on but that’s where that date probably comes from.

Excellent start - great info to get going with Paul. Thanks.
Now to figure out why its happening :joy:

So maybe something is missing in the .fit file and the date is getting defaulted to 1970 in the upload to ZP.
Does anyone involved with ZP know anything about the import process and where it looks for the “Creation Date” ???

Is the date set correctly on the device you are using for dual recording? If the date in the fit file is zero or null that might explain it.

Date in the fit files is all good. I use a Garmin Epix watch as the computer to record the data from Assioma pedals. Been doing it like that for ages with no issues until recently.
When I run the files through fit file fixers which correct date issues etc it makes no difference.
Also when I scan the files data using various online fit file viewers they correct date is always listed in any section where a date is mentioned.

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So it seems like it started happening sometime during Nov 2024. Here are two fit files side by side.
The one on the left is loading into ZP fine. The one on the right is getting assigned a creation date of 1970 on ZP.
It seems like there was a Protocol Version update and a Software update (highlighted in green) and then there is an extra seciton in the new .fit files (highlighted in red) which maybe ZP is not expecting to see and hence assigns the defaut 1970 date :man_shrugging:
But surely I can’t be the only one experiencing this

An app called HR2VP may be causing the issue. I’ll test in the coming days - hopefully tomorrow if I get a chance.
I installed it in Nov 24 while on holiday to help record some rides I was doing on a spin bike at the hotel. And all files since NOV are the affected files. Would be some coincedence :man_shrugging:

I found the problem - what a polava that was :slight_smile:
So the app HR2VP was the issue.


I removed HR2VP from my watch and did a ride this morn - the .fit file uploaded correctly to ZP with the right date.
So my conclusion is it was the HR2VP app causing the issue. I presume its altering the .fit file in some way that ZP import is not prepped for. Looks like ZP is looking for a date in a certain section and in the absence of that date it assigns the file a date of 1970 which is a LINUX default date of some kind according to wikipedia.
heres the 3 files side by side:
The first file is before I started having problems back in Nov 24
The middle file is whats generated with HR2VP installed
The 3rd file is from this morning after I removed HR2VP - its returned to the same format as the first file.
I’d say thats conclusive proof that HR2VP generated .fit file is incompatiable with Zwiftpower.

So ZP doesn’t play well with altered .fit files by other apps. In fairness to HR2VP, when I load the fit file to other websites (comparethewatts for example) there is no issue. The issue only seemed to arrise when imported by Zwift Power.

Thanks Paul - that tip put me on the right track to find the issue.