Before editing a workout, check your diary to be sure that “not synch” does not appear on the workout.
If you edit before the workout has been synced, you might create a duplicate with no workout data.
Then, to edit the workout:
  • Open the desired workout
  • Tap the pen icon
  • Edit the workout
  • Save it (there will be a check mark at the top)

You can delete a workout by going to Diary and pressing the workout you want to delete for 2 seconds. The option to delete it will pop up.
Please note that deleting a workout from your phone will delete it from the web service as well.