Pectoralis Major 
Pectoralis Major muscle:
Pectoralis major muscle: a large and powerful muscle in the front part of the chest. While this muscle is a protector of the chest, it also plays a role in daily activities as well as important sports activities. This muscle is completely superficial and can be touched.
Workouts: This muscle should be strengthened well in various sports, including bodybuilding and resistance training to guarantee the health of the arm joint.
It is in three parts: This muscle is divided into three parts. The part of the chest muscle that is connected to the clavicle is called the upper part, the part connected to the sternum is the middle part, and the lower part is called the lower chest. This category is mostly used in training program design.
Pectoralis Major
“pectoral” L. chest “major” L. larger
Attachments
O: Medial clavicle, sternum, costal
cartilage of ribs 1-7
I: Lateral lip of bicipital groove of
humerus
Actions
• Horizontally adducts and internally
rotates shoulder
• Flexes shoulder (clavicular fibers)
• Extends shoulder from overhead
(costal fibers)
• Adducts or abducts shoulder to
reach shoulder height
Description:
Different tools can be used to strengthen this muscle. Exercises such as lateral push-ups strengthen all three parts of this muscle. Chest press, upper chest, and lower chest press are the main exercises to strengthen this muscle. The declined chest press affects the upper strings and the incline chest press has more effect on the lower strings. The flat chest press strengthens all three parts equally.
By strengthening this muscle, bodybuilding, and weight trainers in various sports, in addition to increasing the performance of athletes, reduce joint injuries in the arm area.
