Pectoralis Minor & rounded shoulders

I work with middle aged students who are very active in fitness activities like running, cycling and weight lifting, I see many with rounded upper backs and forward shoulders and head with very tight muscles in the shoulders and upper arms. I personally work at a computer and phones daily and have a slumping upper back that I am working at correcting too. I noticed in my anatomy books that a tight “Pectoralis Minor” is a possible contributor to pulling the shoulder off the back and forward. It originates at the Coracoid Process (?) and inserts at the 3, 4 & 5th ribs at the front on the chest. It’s the only muscle that has no exercise anywhere that I can find that will stretch it.

The Coracoid Process is a small bone on front of the body, a portion of the shoulder blade. It is the same as Pectoralis major just more specific. To really stretch it the best approach is hands on bodywork. It is too small a muscle and deep for yoga to stretch without supervision of one who knows anatomy intimately.

I’m looking at strengthening the “Latissimus Dorsi”, which attaches to the tip of the Scapula, to help counteract it by pulling it back down at the back. Is there any other exercise(s) that will stretch it? Thank you for your time, A

The latissimus does not attach to the scapula but to the upper arm humerus. For improving rounded shoulders I recommend you consult my book SYT in chapter 22, which is entitled correcting Posture and see the specific recommendations on page266. Especially look at strengthening the latissimus not stretching it. Rounded back is a sign of overstretched muscle. Recommendations include cobra, bridge, plank, in general all backbending poses.