The Triceps Muscle - Explained

The only muscle to be found in the back of the arm, the triceps brachii, a large and thick muscle in fact originates from three heads, hence its name. The three heads are; the long head, medial head and lateral head. Some say it is shaped like a horseshoe. The lateral and long heads cover most of the medial head as shown above. The triceps brachii is used to stabilise the shoulder and straightens the elbow joint. From a flexed position the long head can adduct and extend the humerus. When throwing objects or pushing a door closed it is the triceps brachii that it being used. Causes of pain include; repetitive motion injury, repeated arm action including from sports such as tennis and basketball and lifting heavy objects with the palm upward facing. For more information about NAT online courses, please visit