So this is something that I don't understand with multi-sport traning activities. I would call this a bug, and here is the long version on how i found it.
- Create a multi-sport training activity
- Add three running segments and save everything is stored as three segments
- Changed first segments running activity to warmup 500m, press done and then save
- Changed last activity to cooldown 500m, press done and then save.
- Changed secod activity to contain only laps where the lap had 3 activities. Running 500m, Rest 500m, and Other Press lap button. Press done and then save.
- Garmin connect suddenly merges either warmup or cooldown activity into the middle activity <-- This is what i call a bug
This seems to have a workaround if i add segments in the middle activity with 0.01m, but the workaround is not guaranteed to work...