Teres Major

This course describes the anatomy and integrated function of the teres major muscle (a.k.a. little helper or little brother to the latissimus dorsi muscle). This muscle originates on the inferior angle of the scapula (shoulder blade) and inserts on the lesser tubercle of the humerus (upper arm bone). The teres major muscle lies just inferior to the teres minor muscle; however, the teres major is not a rotator cuff muscle. The teres major is composed primarily of type II muscle fibers, but type I muscle fibers still compose 40%. The teres major muscle crosses the shoulder joint (glenohumeral joint), and contributes to shoulder adduction, shoulder extension, and shoulder internal rotation (medial rotation). This course also describes the role of the teres major muscle in glenohumeral arthrokinematics, fascial integration, postural dysfunction, and subsystem integration. Sports medicine professionals (personal trainers, fitness instructors, physical therapists, massage therapists, chiropractors, occupational therapists, athletic trainers, etc.) must be aware of the integrated function of the teres major for the detailed analysis of human movement, and the development of sophisticated exercise programs and therapeutic (rehabilitation) interventions. Further, this course is essential knowledge for future courses discussing injury prevention and physical rehabilitation/physical therapy (e.g. loss of extensibility (tight shoulders), teres major strain, rotator cuff muscle injury, tendon rupture, shoulder impingement, upper crossed syndrome), the synergistic function of the teres major (e.g. synergistic function with the latissimus dorsi, but not the rotator cuff muscles or shoulder blade muscles), and teres major exercises and techniques for enhancing sports performance (e.g. ensuring ideal teres major length for optimal shoulder stability, strength, power, upper arm, and back hypertrophy).

Brookbush Institute’s most recommended techniques for the Teres Major (see videos below):

• Release: Teres Major and Latissimus Dorsi Static Release
• Stretch: Teres Major and Latissimus Dorsi Static Stretch
• Stretch: Teres Major and Latissimus Dorsi Dynamic Stretch

Caption: Teres major muscle highlighted in a cadaver dissection