I've updated the app today and trying to enter the "workout" section now crashed the app instantly.
All-
This report has been resolved with the release of the iOS Garmin Connect mobile app version 4.53.1. If you are running 4.53.1 and still experiencing this issue, please start a new thread.
They updated in App Store today with a fix. Download (on iOS it’s version 4.53.1) and it should be fixed for you.