S3 | Prone Isometric Y's (135 deg)

INSTRUCTIONS Lay on your stomach with your active arm extended into a “Y”position with your hand on a yoga block or book. The Y position reflects 135 deg of abduction, which is halfway in between 90 degrees abduction and 180 degrees abduction. Keeping your shoulder blade back, aim to push down into the block "from the shoulder" so you stabilise at the shoulder for the required time