It might be available on line or somewhere but I don’t see where to track progress from one workout to the next?
Connect Stats could be what you are looking for:
https://itunes.apple.com/app/apple-store/id581697248?pt=233641&ct=blog&mt=8
You will have to use the web to do that.
To export to CSV you can use the activities page: https://connect.garmin.com/modern/activities
Filter in any way you like and then export.