Open "add a workout" in the calendar and the menu that says "select a workout" has a STS option. If you go to that, all the discs are available. You can set up Meso 2 & 3 as you like them. You can also go to rotations, on the top menu, and choose, "create a rotation" and work from there to use STS Meso 2 & 3 as you like.