Start in a half kneeling position, one knee on the floor and both your hips and knees bent at 90 degrees.
Hold one end of a resistance band in your sound limb.
Place the other end of the band under your same side knee.
Start with your elbow bent and your hand in front of your shoulder, and make sure there is tension in the band.
When ready, press your hand up towards the ceiling until your elbow is straight.
Control the movement as you return to the starting position and repeat.