Stand up straight facing a wall.
Loop a resistance band around both of your wrists.
Place a foam roller horizontally on the wall and lean on it with your forearms.
Your forearms should be vertical with your hands pointing up to the ceiling.
There should be some tension in the band with your arms around shoulder width apart.
Walk your feet back a little while leaning forwards on the foam roller.
Ensure you keep a straight line from your head to your heels.
Drive your forearms into the foam roller, flattening your shoulder blades against your ribs.
Do not hunch your shoulders up, or round your upper back.
Keeping this control with your shoulder blades, roll the foam roller up and down the wall.
The key to this exercise is to ensure your shoulder blades remain tight against your rib cage, and your forearms remain in the same parallel, vertical position throughout.