What is the term for the position where palms and forearms are facing up?

The term that describes the position where the palms and forearms are facing up is "supination." This anatomical term specifically denotes the rotation of the forearm and hand such that the palm is directed upwards or forward, depending on body orientation. Supination is often compared with pronation, which is the opposite movement, where the palms face down.

Understanding supination is crucial in various fields, including sports medicine, as it affects how certain exercises are performed and how movement patterns are analyzed for activities such as throwing or lifting. This knowledge helps professionals in the field assess and design appropriate training regimens while being aware of how different positions may impact performance or injury risk.

The other terms mentioned in the options refer to different concepts altogether. "Supine" refers to lying on one's back, "superficial" describes a position closer to the surface of the body, and "synarthrosis" defines a type of joint that allows for very little or no movement. Thus, knowing the specific definitions helps clarify the accurate use of anatomical terms in practice.