What action is performed by the triceps muscle?

The triceps muscle is responsible for the action of elbow extension. When the triceps contracts, it pulls on the olecranon process of the ulna, straightening the elbow joint. This action is crucial for various daily activities, such as pushing, throwing, and performing exercises like push-ups or bench presses where extending the arm is required.

In contrast, knee flexion, elbow flexion, and plantarflexion of the ankle involve different muscle groups. Knee flexion is primarily performed by the hamstring muscles, elbow flexion is facilitated mainly by the biceps brachii, and plantarflexion of the ankle is carried out by the gastrocnemius and soleus muscles. Understanding these functions helps clarify the specific roles different muscle groups play in movement.