What does supination refer to?

Supination specifically refers to the movement of the forearm and hand in which the palm faces forward or upward. This motion occurs at the radioulnar joints, where the radius and ulna are located. When you supinate your forearm, you rotate it in such a way that the palm is oriented upward, which is the anatomical position for the upper limb. This is an important concept in anatomy and physiology, particularly when discussing movements related to the upper extremities, as it helps in understanding how the body interacts with different physical activities and forces.

In contrast, the other options describe different movements or positions: rotation of the forearm so the palm faces downward describes pronation, while movement extending overhead does not align with the concept of supination. Twisting of the trunk pertains to torso movements and is unrelated to the specific action of supination. Understanding these distinctions helps clarify the different terms associated with limb movements.