The shoulder joint is a synovial joint and being able to roll and glide in all directions can help keep things fluid so the batteries (aka: mechanoreceptors) don’t get dried out. Unlike traditional exercises for the rotator cuff like banded external rotation or I’s, Y’s, and T’s, this closed chain activity is focused more on the relative roll and glide at the shoulder and the opposite relative motion at the elbow. Rather than thinking about “muscles” I am thinking about creating fluid space to c