The triceps brachii is a large three-headed muscle located on the posterior side of the upper arm that functions as the primary extensor of the elbow joint. It enables pushing movements, straightening of the arm, and stabilization of the shoulder joint during various activities. The triceps works antagonistically to the biceps, providing crucial balance and control to arm movements.
The name "triceps brachii" comes from Latin, where "triceps" means "three-headed" (tri = three, ceps = heads) and "brachii" refers to the arm. This anatomical name directly describes its structure with three distinct muscle heads that converge into a single tendon.
Without functioning triceps brachii muscles, humans would be unable to straighten their arms against resistance or effectively push objects away from the body. Activities requiring arm extension such as pushing doors, performing push-ups, throwing objects, or even simple tasks like pushing oneself up from a seated position would become difficult or impossible.
