Is there a way to recover the data of a training session that was not saved my laptop died three quarters through the workout and I had to restart.
Piet Prinsloo
You might be able to get some of the data here: https://my.zwift.com/
Or you can look in \Documents\Zwift\Activities and you will find the .fit file there.
There is no way to manually upload .fit files to Zwift.
Thanks Paul, can I upload the data to Garmin?
You should be able to manually upload the .fit file to any 3rd party site including Garmin.
Yes you can.