Merging activities

Just a guess, but I think Garmin Connect is probably using the total distance in the FIT session record (which is like the activity summary in the UI), whereas Strava might recalculate the distance by adding up the distances between the individual GPS points. (At least that's what seemed to happen in the past when Strava would add additional distance which didn't exist in Connect, for an activity that had GPS dropouts.)

So I'm guessing that FIT File Tools didn't write the FIT session record correctly. You can try to confirm this theory by uploading the merged FIT file to https://www.fitfileviewer.com/, clicking on the Session row and checking the total distance column.

Do the splits and GPS tracks match up in both Connect and Strava? If so, you could probably get away with editing the distance in Connect, which should cause other activity summary info like average pace to be corrected.

Well, according to this Strava support article, Strava will only recalculate distance if the device did not provide distance information in the original file:

https://support.strava.com/hc/en-us/articles/216919487-How-Distance-is-Calculated

So I'm not sure why Strava would recalculate distance in this instance, unless it found something wrong with the data.

But hopefully the fit file viewer will shed some light.

I uploaded the file and it shows the distance as 102,395.91m.  I'm not sure how that translates.  

That's 63.626 miles. So the FIT file session record is correct I guess, but for some unknown reason, Connect is showing something else.

Unless there's some other obvious discrepancy in the splits or GPS track, I have no idea what's happening here.

Personally I would probably just keep the original two split activities in Connect, and leave the merged one in Strava (for public consumption). (Here I'm assuming that you don't share your Connect activities publicly, and/or that Strava is your primary way of sharing activities.)

You could also try a different tool for merging FIT files and see if you get better results: [https://gotoes.org/strava/Combine_GPX_TCX_FIT_Files.php]

I attempted that one also, same results.  I guess it is what it is.

Zip the 2 files then attach it to this thread. Might be something we can fix for you.

• Zip the files, then in a reply post Insert >> Image/video/file >> click Upload >> browse for file >> OK.
• Or upload the fit files 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.

[solved]

This will work. Comes out to 63.63 miles  - [solved]

If you get a message that it's already uploaded, you'll need to delete the 34.65 mile activity since it starts at the same time as the merged activity.

Merged using Fit File Repair Tool "append mode"

And congrats on the performance.   

Oh man, it worked.  I wish I knew what you did differently than me, but I appreciate it.  Thank you!!!

Jeff said:

I wish I knew what you did differently than me

Did you use Fit File Repair Tool? You said you used FIT File Tools, which is a different application.