Garmin Connect Export Data

Hi Everyone,
I hope the weekend is going well.

I have a rather technical question. All my Strava data was deleted some weeks ago and I’m trying to recreate it by piecing it together from different services I use in parallel or used in the past.

I’m now trying to use the Garmin Connect data and after receiving the link to all my data I’m struggling with all the .fit files it provided. I received, amongst others, 5 compressed files and what I’m realizing is that most of them are not recognized by Strava (most have either 1 KB or very low numbers).

My questions are then, what are these files? Is there a way to identify / filter the ones that are recognized by Strava? Can I somehow recognize the runs / swims (vs cycling for example)?

Thanks as always for the help!