Garmin delayed delivering activity files to us starting around April 16, 2026 at about 00:30 UTC. Garmin is now sending the delayed activities to AI Endurance. Hopefully Garmin will resolve the issue promptly and deliver all the missing activities quickly. If you don’t want to wait you can also upload individual fit files via the fit file upload on the ‘Apps’ page.
If you have Garmin and Strava connected: When the activity finally arrives (either delayed from Garmin or via you manually uploading the fit file) if it has HRV data, it will automatically replace the Strava activity.
Is this still an ongoing issue? I thought it had been resolved but my workouts from yesterday and this morning don’t seem to have sync’d. They are syncing fine to TrainingPeaks and intervals.icu though.
the delays stopped for a while but have started again recently, will keep a close eye and continue to investigate what’s going on and keep you updated
Seems it is still ongoing today.
yes unfortunately. how long was your delay?
After 16 hours I manually uploaded the activity that hadn’t been fetched yet.
Haven’t been uploading here for at least the last 3 days. And still don’t.
Update: still experiencing massive delays. Have now changed the pipeline to log the delay on every import so over the weekend we should gather a good amount of data we can pass on to Garmin if the issue persists.
Thanks everyone for your patience
Final update (hopefully): it was actually a problem on our side.
Explanation: When Garmin sends the Ping that the activity is ready to download, we store that in database. As platform grows that table in database grew to a point that looking up if the activity was already imported (sometimes Garmin sends duplicates) took so long that the endpoint timed out, which from Garmin’s end is a failed delivery. If failed Garmin tries again, which made the problem even worse once it had started because the total number of Pings and hence table grew significantly with all the retries added.
Fix was simple (add an index to table for looking up the combination of userId and activityID) but it took a long time to find the problem because all we were aware of for a long time were the delayed deliveries from Garmin (which were actually retries as described above - but we didn’t know they were).
The fix went out Friday night 10 pm EST and I haven’t seen any problems since (Garmin activity delivery is now within seconds to a few minutes after activity completes as before) and I haven’t heard any complaints since then. So hopefully all is good now.
Thanks for your patience everyone.