Brachialis
Main muscle in chest. Originates in the medial end of clavicle, sternum, and ribs 1-6. The main action is adduction and medially rotating the arm.
Diaphragm
External obliques
Origin is femur (linea alba). Allows knee extension. Example: quads (most medial)
Latissimus Dorsi
Deltoid
Vastus Lateralis
The insertion is the greater trochanter of femur. The action is it allows abduction and extension of hip.
Internal Intercostals
The origin is the clavicle and scapula. The insertion is middle of the lateral surface of humerus (deltoid tuberosity). Allows abduction of shoulder, laterally rotate arm
the insertion is the central tendinous sheet. This muscle allows contraction which expands the thoracic cavity; changes pressure in the thoracic cavity to allow air to be drawn into the lungs.
Pectoralis Major
the insertion is the inter-tubercular groove of humerus.Origin is spinous processes of T7-T12.
origin is femur (greater trochanter) and the action is that it allows knee extension. (most lateral)
the origin are ribs 2-12, superior border of each rib. The insertion is ribs 1-11, inferior border of each rib.The depress the ribs and decrease space in chest cavity.
Originates in the humerus. This muscle extends down arm and inserts on the coronoid process and tuberosity of ulna.
Gluteus Medius
Vastus Medialis
Helps flex and rotate the vertical column as well as compress abdomen, depresses ribs. The insertion is the linea alba and iliac crest