When you don't want to do a set, you can remove it (swipe) or simple ignore it. But this seems to confuse many users, and the app will still try and make you do that set, unless you check a set in a further exercise.

Solution: add a discreet "Skip" button, that will change the way the set is displayed (maybe a light blue shade, as if it was frozen?), and take it out of the sets to do in the session logic.

We could display that button on swipe: instead of directly deleting the exercise on swipe, it could show two options (skip or delete).