When STS was created (in 2009?) Cathe stressed the importance of the rest week from heavy weight workouts. And other "experts" recommend it as well because it takes awhile longer for your tendons and cartilage to catch up with muscle recovery. But if you notice in her monthly rotations, she suggests one or two rest days. When I did STS this past year, I did cardio, walking, stretching and metabolic weight workouts with lighter weights during the rest week. I think I lifted better after the recovery week. It's your workout, pay attention to how you feel and plan accordingly. Best wishes for your STS journey