Question

Shoulder Extension (Posterior Deltoid)

Answer 1

The posterior deltoid is a shoulder muscle that extends and laterally rotates the arm.

Step-by-step explanation:

The posterior deltoid is a shoulder muscle that extends and laterally rotates the arm. It is part of the deltoid muscle group, which also abducts the arm, flexes and medially rotates it. The deltoid is a thick and round muscle that contributes to the rounded lines of the shoulder.