In Plain English
The triceps long head is the largest of the three triceps heads, running from the shoulder blade to the elbow along the inner back of the upper arm. Unlike the other two triceps heads, it crosses both the shoulder and elbow joints, allowing it to straighten the elbow while also helping move the upper arm behind the body.
Technical Definition
The long head of the triceps brachii originates from the infraglenoid tubercle of the scapula and inserts onto the olecranon process of the ulna. Because it crosses both the shoulder and elbow joints, its primary functions include elbow extension and shoulder extension. This unique anatomy allows it to contribute to both pressing and pulling movements while making shoulder position a major factor in exercise selection.

















