Hello @DivePV
I just checked on mine and I can’t see anywhere to do it in the App at all. The only things you can do are edit the times, sometimes distance and the name of the exercise. There doesn’t seem to be anywhere or any way to do this.
I was going to suggest adding this as a Feature Suggestion though as it could be useful to other people too but then searched and found the next piece of information.
Feature Suggestions
I just checked and people have before but the thread was closed and new threads were merged to it it seems. You can still vote for it though.
Add notes to Activities
I hope that helps a bit.
