The Anti-Rotation Press exercise works your shoulders and abs.
This exercise works the muscles in your shoulders as well as the muscles in your core. As you perform the exercise, make sure you're maintaining a slight bend in your knees and that your shoulders are back and down. At the end of the movement, you should feel the band pulling a strongly back towards the origin point and your core has to really brace to prevent you from twisting towards the door. As you work, make sure you're tailbone stays relax and down. Your spine should be in a neutral position so you really feel that challenge in your abdominals.