10/25/2025
Notice that two are connected to the thorax from the front, and three from the back.
Implications:
The anterior muscles are also accessory breathing muscles. Meaning that if you fix the arm against something stable, they will help expand the ribcage and make it easier to get air in your body.
The upper back is also intimately related to shoulder blade movement; Elevating the shoulder makes it easier to round the back. It’s also easier to rotate the upper back when the shoulder blade is elevated. Try it! Shrug upward when working on upper back mobility (even in daily life like wiping on the toilet).
And conversely, depressing the shoulder relates with keeping the back more stable and straight- it’s the reason that a cue for shoulders down and back also helps reinforce a person’s arch on bench press.
It’s easier to feel than to think through, so try it for yourself and share any insights you have!!!
Illustrations shared with permission from www.kenhub.com . Illustrator: Yousun Koh