Elbow extension is the movement that straightens the arm at the elbow joint. This action occurs when the triceps brachii muscle contracts, pulling on the olecranon process of the ulna bone. Elbow extension is essential for various daily activities, such as pushing, throwing, and reaching. During elbow extension, the angle between the upper arm and forearm increases, moving from a bent position to a straightened one. This movement is crucial in sports and physical activities, allowing for effective arm use in actions like lifting or pushing objects away from the body.