Final answer:
Supine arm work refers to the movements and muscles involved when a person is lying on their back and performing actions with their arms. Specific muscles are activated to perform actions such as abduction, flexion, and pronation of the forearm. Key muscles involved include the deltoid, triceps brachii, brachioradialis, pronator teres, and pronator quadratus.
Step-by-step explanation:
Supine arm work refers to the movement and muscles involved when the person is lying on their back with their upper limbs and lower limbs touching the sides of their body. In this position, certain muscles are activated to perform various actions.
When the anterior fascicle is stimulated, the arm will abduct (move away from the midline) and flex (move anteriorly) at the shoulder joint. Some of the key muscles involved in supine arm work include the deltoid, triceps brachii, and brachioradialis.
The movement of the forearm from a palm forward to a palm backward position is called pronation. This motion is important in supine arm work and involves muscles such as the pronator teres and pronator quadratus.