I melted my brain trying to logically figure out which way upward rotation is, totally unnecessarily as it turns out, because I could have just looked at the picture in the supplemental Fitness Professionals' Guide to Musculoskeletal Anatomy and Human Movement that came with all of my ACE study materials, and that I didn't even open until I had struggled through eighteen weeks of human anatomy by myself. Argh.
What movements happen at this joint?
So upward rotation is when the shoulder blades turn—imagine two dials—toward your spine and downward rotation is when they turn away from your spine, and by the way, these happen when you abduct and adduct your arms at your shoulders.
What muscles make these movements happen?
The muscles that upwardly rotate your shoulder blades are your upper and middle trapezius, rhomboid minor and major, and serratus anterior.
The muscles that downwardly rotate your shoulder blades are your pectoralis minor and rhomboid minor and major.
What exercises make these muscles work?
Since upward and downward rotation at the shoulder girdle happen along with abduction and adduction at the shoulder, any exercises that work those shoulder muscles also work the shoulder girdle muscles. Stay tuned...