Seated Arnold Press

Sit with a dumbbell in each hand at shoulder height, palms facing you and elbows in front of your body rather than out to the sides. As you press up, rotate your palms outward so they finish facing forward at the top, arms locked out above your ears -- the rotation partway through the press is what separates this from a standard shoulder press. Reverse the rotation as you lower, ending back with palms facing you and elbows tucked in front of your chest. That twisting path works your front and side shoulders through a wider arc than a press that stays in one hand position the whole time. Keep your back against the seat rather than arching to help the weight up.