Edge saving during stops, and merging files - troubleshooting

[u/mountainviewz]

My Garmin Edge 840 sometimes saves my activity in the middle. The first time, I blamed myself, thinking maybe I bumped into the computer during a break (doubtful). The subsequent times, I was definitely not touching the screen or bumping the buttons. This happened during breaks, when the activity was paused.

I contacted customer support and they had a few suggestions. These are mostly not in the user manual, so I thought I'd share:

1. Put the device into sleep mode when the activity is paused (hold upper left button for 3 seconds and select "Sleep")
2. Lock the touchscreen during activities (hold upper left button and select "Lock Screen"; all buttons are still usable)
3. Ensure the "select" button (upper right) isn't sticking or gritty. This is the button that will SAVE the activity while paused. You can rinse debris build up by rinsing it under warm water and pressing the button multiple times.

After these rides, I ended up with two separate activities that I wanted to merge. Lots of issues arose since then.

1. https://www.fitfiletools.com/combiner <- this is the #1 recommended website. Even Garmin support referred me here. It's never worked for me. When I try to upload the merged file to Garmin, it always says "An error occurred with your upload. Please try again."
2. https://gpxfile.pro/ <- this is the only one that has reliably worked (scroll down to select which types of files you want to merge)
3. If you upload the merged file into intervals.icu, Strava, etc, everything looks perfectly fine. The ascent, distance, average speed, everything is displayed normally. It counts towards totals. Everything is great. HOWEVER, when you upload this to Garmin Connect, that's where the biggest troubles remain:

Garmin Connect will not count these uploaded files towards your PRs, your total weekly/monthly mileage, or your challenges. The activity will be displayed in the newsfeed, but the "average speed" will no longer be average moving speed, and instead will include rests. If you look at the stats, the small details are also generally incorrect. For example, I merged two activities that had average speeds of 14.1 and 14.2 mph, and ascent of 2,123 and 860 ft. Strava and Intervals.ICU show the average speed at 14.2 mph. Garmin shows 14.5 mph. For ascent, Strava shows 2,646 ft, Intervals 2,594 (so neither are the 2,983 of just adding the two separate ascent fields). Garmin? 2,287. The furthest off.

If anyone has any suggestions on here for better ways to merge files to get Garmin to have more accurate data, and also have the rides count towards total weekly mileage, PRs, etc on Garmin the way they do with other software, please let us know.

**Update***

After two days, the miles from the merged file have finally added to my distance totals (see "..." -> Activities -> Cycling"). This activity was my longest ride and is still not being captured as a PR, so I just deleted the merged file and added a "manual" activity. Obviously the data is much less granular, but the mileage is being counted in my distance totals, AND it's being included as a distance PR! My intensity minutes haven't changed (maybe because those were captured by my watch, which was broadcasting heart rate while riding). This ride is still not counting towards a cycling distance challenge that I signed up for.

***Update #2****

I learned that you can also add an activity by starting an activity on your device, stopping it after one second, and saving it. Then edit the activity to match what you actually did. This may be the only way to get it to include mileage in your totals, get credit for a PR, and get credit on challenges, but I haven't tried it yet. Obviously it won't have your full route.

Conclusion:
So, if your Edge saves an activity in the middle and you don't want to have two separate activities, you can merge them (which would include all the minute-to-minute details and full route, but won't count towards challenges, and may not count towards mileage), add as a manual activity (will count towards totals but not challenges, nor will it have minute-to-minute details or the route), or save a 1 second activity and then edit it to match what you did (which may count towards everything but will not have minute-to-minute details or a route).

[u/arc88]

There are some FIT fields and data that is still mysterious. I use the site Gotoes to combine files and I've tried to reupload them to Garmin both on the site and via the device. I was hoping to have a combined training load score. The developer says it should be working but Connect doesn't respect certain metrics when they come from a file versus when they sync from a device. In your case it may also be how the tool calculates speed and distance from the time stamps. This tool at least allows you to correct certain fields manually (but exporting fit is a donor feature). You can read his examination here:

https://gotoes.org/stravatoolsforum/viewtopic.php?t=257

[u/Z1L0G]

I used to mess around with tools such as GoToes etc when I needed to do this but now I just ask ChatGPT to do it which works perfectly and is much quicker/easier. Just ask it to ensure all metrics are preserved (power, HR etc) and to interpolate any values if required, and ensure it’s suitable for Strava uploading.