Demonstrate the action of pectoralis major and minor?

The pectoralis major and minor are muscles located in the chest region.

The pectoralis major is a large, fan-shaped muscle that covers the upper part of the chest. It originates from the clavicle, sternum, and the cartilage of the ribs, and inserts into the humerus.

When the pectoralis major contracts, it pulls the arm across the body in a movement known as horizontal adduction. This muscle is responsible for movements such as pushing, throwing, and hugging.

The pectoralis minor is a smaller muscle located underneath the pectoralis major. It originates from the third, fourth, and fifth ribs and inserts into the coracoid process of the scapula.

When the pectoralis minor contracts, it pulls the scapula forward and downward, helping to stabilize the shoulder joint. This muscle is involved in movements such as reaching forward and downward.

To demonstrate the action of the pectoralis major, you can place your hand on your opposite shoulder and push your elbow across your body. You should feel the muscle contracting as you perform this movement.

To demonstrate the action of the pectoralis minor, you can place your hand on your chest and push your shoulder forward and downward. You should feel the muscle contracting as you perform this movement.