Media controls for stopping and skipping exercises
Because there is a variety of exercises that have to be done in different positions, it’s not possible to have your phone at a location where you can see it at all times. With only 10 seconds between exercises, it’s not very practical to come back to your phone to check which exercise is next, especially if the next exercise is supposed to be done with a chair, step or table etc. — sending a push notification with the name of the exercise can be especially useful for people who wear smart watches (ex. PineTime); as they can check the notification on their smart watch to see which exercise is next. I guess this could be an optional feature.
EDIT: Rather than a push notification, media controls would be more appropriate — see conversation below.