Isometric wall angel (Shoulder external rotation/scapular retraction strengthening isometric, standing to wall)

Stand up straight with your back against a wall.
Bend your elbows and rotate your forearms outwards so that the backs of your hands touch the wall.
Allow your upper arms to move away from your sides a little.
Maintaining this angle, press the backs of your forearms and wrists into the wall.
Hold this position.
You may be asked to perform this exercise with your upper arms further away from your sides.