Pectoral muscles (colloquially referred to as "pecs") are the muscles that connect the front of the human chest with the bones of the upper arm and shoulder. This region contains four muscles that provide movements to the upper limbs or ribs. Gray411

Pectoralis major The pectoralis major () is a thick, fan-shaped or triangular convergent muscle, situated at the chest of the human body. It makes up the bulk of the chest muscles and lies under the breast. Beneath the pectoralis major is the pectoralis minor, a ...

is a thick, fan-shaped or triangular convergent muscle, which makes up the bulk of the chest muscle. It lies under the breast. It serves to flex, extend, and rotate the

humerus The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a roun ...

, the long bone of the upper arm. Pectoralis minor is a thin, triangular muscle located beneath the pectoralis major. It attaches to the ribs, and serves to stabilize the scapula, the large bone of the shoulder. The pectoral fascia is a thin layer of tissue over the pectoralis major, extending toward the latissimus dorsi muscle on the back. Along with the pectoralis major and pectoralis minor, the subclavius muscle forms the axilla or armpit. The subclavius moves the shoulder downward and forward. Serratus anterior is another muscle on the front of the chest. It moves the scapula forward around the torso, as when throwing a punch. Between the ribs are various groups of intercostal muscles, which help with breathing.

References

* {{cite book, last1=Gray, first1=Henry, last2=Lewis, first2=Warren, year=1918, title=Anatomy of the Human Body, location=Philadelphia and New York, publisher=Lea and Feibiger, edition=twentieth, url=https://archive.org/details/anatomyofhumanbo1918gray, access-date=13 September 2016 Muscles of the torso Broad-concept articles Human anatomy