Don't: Let your shoulders come up to the ears.
Instead: Engage your lower Trapezius muscle to keep the shoulder blades in place.
Don't: collapse into protraction (bringing your shoulder to the front)
Instead: "Smile with your collarbones" keeping the shoulders wide & strong
Why do we need an open/mobile spine? Besides doing cool-looking backbends the thoracic spine is the anchor of the ribs. The ribcage is the anchor of the shoulder blade. The shoulder blade is the anchor of the humerus (upper arm bone). So the thoracic spine is the base we're building our arm movem...