Sit in your wheelchair with your feet resting on the footrests, and ensure the brakes are applied.
Loop a resistance band under your wheelchair and hold one end in each hand.
Pick up the slack in the resistance band by wrapping each end around your hands.
Allow your arms to rest on either side of your wheels.
When ready, shrug your shoulders towards your ears against the resistance of the band.
Hold briefly before returning to the start position.
Repeat.