Exploring the biceps brachii muscle
The biceps brachii is the first of three muscles we’ll look at that primarily work to move the forearm. This is a muscle that is likely familiar to you as we use it a lot in everyday life. We use biceps brachii for everything from lifting a glass of water to turning a doorknob.
What does biceps brachii muscle mean?
- “Bi” means two.
- “Ceps” means head.
- “Brachii” is related to the Latin word “brachium” which means upper arm.
You could put all of that together to get: “a two-headed muscle located on the upper arm”.
Where does the biceps brachii muscle attach?
Biceps brachii is superficial and therefore easy to see. Its two heads are called the long head and the short head.
Origin of biceps brachii muscle
The long head of the biceps brachii originates on the supraglenoid tubercle of the scapula. It runs over the head of the humerus, through the bicipital groove, and then joins with the fibers of the short head. The short head originates on the coracoid process of the scapula.
Insertion of biceps brachii muscle
After both heads come together, the muscle runs past the distal end of the humerus to insert on the radial tuberosity.
What actions does the biceps brachii muscle do?
Biceps primarily flexes the elbow and supinates the forearm (brings the palm facing up). At the shoulder joint it also assists in flexion of the shoulder. Additionally, the short head can pull the arm in toward the midline which we call adduction.
What are the most common injuries to the biceps brachii muscle?
One of the most common injuries to biceps brachii is biceps tendinitis. Biceps tendinitis usually results from overuse from sports. It’s common in swimmers, baseball players, tennis players, and others. It can also occur as a normal part of aging. Symptoms include:
- Pain and inflammation, usually around the long head of biceps brachii at the anterior part of the shoulder.
Consult your physician for assessment and treatment recommendations.
Postures where this muscle contracts
In postures where we raise our arms over our head, biceps brachii assists in both flexion and adduction of the shoulder joint through a concentric contraction.
In shoulderstand (below) we see the biceps contracting isometrically to help keep our spine straight and lifting.
Postures where this muscle is lengthened
In purvottansana biceps brachii is lengthened at the shoulder joint because we are extending it. If we have our fingers facing forward, we have also pronated our forearm, which adds just a little more length to the biceps.