Discover the Surprising Muscle Under Your Arm and Get Answers to 6 Common Questions!
The muscles under your arm are the Axillary Muscle Group, Pectoralis Major, Subscapularis Muscle, Latissimus Dorsi, Teres Major Muscle, Coracobrachialis Muscles, Biceps Brachii Muscles, Triceps Brachii Muscles, and Serratus Anterior Muscles.
Contents
- What is the Axillary Muscle Group?
- What is the Subscapularis Muscle?
- What is the Teres Major Muscle?
- What are Biceps Brachii Muscles?
- What are Serratus Anterior Muscles?
- Common Mistakes And Misconceptions
What is the Axillary Muscle Group?
The Axillary Muscle Group is composed of three main muscles: subscapularis, pectoralis minor and teres major. Subscapularis is the largest muscle in the group and helps to stabilize the shoulder joint. Pectoralis minor assists with arm rotation and adduction, while teres major helps with activities such as throwing, lifting and pushing. Weakness or injury to these muscles can lead to pain or decreased range of motion in the shoulder joint. Strengthening exercises such as push-ups, pull-ups, rows and lateral raises can help improve strength and stability in this area. Stretching exercises, foam rolling and massage therapy can also be beneficial for relieving tension from tight axillary muscles. It is important to consult a doctor if you experience persistent pain or limited mobility due to an injury involving your axillary muscle group.
What is the Subscapularis Muscle?
The Subscapularis muscle is a rotator cuff muscle located under the arm. It originates from the front surface of the lower part of the shoulder blade (scapula) and inserts onto the lesser tubercle of the upper arm bone (humerus). It is an internal rotator and adductor of the shoulder joint, helping to stabilize it during movement. It is innervated by the subscapular nerve and can become weak or painful when overused or injured. It can be strengthened with exercises such as wall slides, band pull-downs, and external rotation exercises. Common injury sites include bursitis and tendinopathy, and treatment typically includes rest, ice, physical therapy, and sometimes surgery. It is especially important for athletes who use their arms frequently.
What is the Teres Major Muscle?
The Teres Major muscle is a muscle located in the shoulder region that attaches to the humerus and scapula. It helps with adduction, internal rotation, and extension of the arm. It originates from the inferior angle of the scapula and inserts at the intertubercular groove of the humerus. It is innervated by the lower subscapular nerve (C5-C6) and has a synergistic action with the latissimus dorsi muscle. It is composed of slow twitch fibers and is involved in activities such as throwing a ball or lifting weights. It can be injured through repetitive overhead motions and strengthening exercises can help prevent injury. It is commonly referred to as the “shoulder blade squeezer” and may be affected by rotator cuff injuries. Anatomical variation may exist between individuals.
What are Biceps Brachii Muscles?
The Biceps Brachii muscles are a pair of muscles located in the upper arm that flex the elbow joint and supinate the forearm. They originate at the scapula and humerus and insert at the radius and ulna. They are composed of a short head and a long head and are innervated by the musculocutaneous nerve. Synergists of the Biceps Brachii muscles include the brachialis, brachioradialis, and coracobrachialis muscles, while the triceps brachii muscles are antagonists. The Biceps Brachii muscles can be strengthened through exercises such as bicep curls, chin ups, and hammer curls, but can be weakened through overuse or injury. They are commonly injured during weightlifting activities and can be stretched with a supination exercise. The Biceps Brachii muscles are also an anatomical landmark for locating the pulse and are important for everyday activities such as lifting objects.
What are Serratus Anterior Muscles?
The Serratus Anterior Muscles are a group of muscles located under the arm that connect to the ribs and scapula. They are responsible for protraction of the scapula and help with shoulder blade movement. They are involved in pushing, pulling, and breathing motions and originate from the upper eight or nine ribs, inserting into the medial border of the scapula. The Serratus Anterior Muscles are innervated by the long thoracic nerve (C5-C7). Weakness in these muscles can lead to winging of the scapula and can be injured due to overuse or trauma. Pain may be felt when pressing on the muscle area and tightness can cause pain in the neck, shoulders, and back. Strengthening exercises such as push-ups and planks can help strengthen the Serratus Anterior Muscles, while stretching and massage therapy can help improve flexibility and reduce tightness.
Common Mistakes And Misconceptions
- Mistake: The muscle under your arm is the bicep.
Explanation: The biceps are located on the front of the upper arm, not underneath it. The muscle that lies beneath your arm is called the latissimus dorsi (or lats). It’s a large, flat triangular-shaped muscle that extends from your lower back to your armpit and helps you move your arms in different directions. - Mistake: There is no muscle under my arm.
Explanation: As mentioned above, there is indeed a muscle located beneath your arm – the latissimus dorsi or lats for short. This powerful muscle helps you perform activities such as pulling and pushing motions with both arms simultaneously, making it an important part of any exercise routine.