The Power Arc Exercise Device is a portable, lightweight exercise device that strengthens the muscles used in sports requiring strong rotation of the body. Examples of sports that require strong rotation of the trunk and hips include baseball batting, golf and tennis. The Power Arc Exercise Device uniquely exercises the exact muscles used to produce rotation. The Power Arc Exercise Device also provides resistance to the muscles of rotation in an optimum direction. The optimum direction of resistance for any exercise device is a ninety degree angle to the direction of the body's movement. Exercise bands provide linear resistance only to movement that is in a rotary direction and as such do not provide effective resistive exercise. The Power Arc Exercise device enables athletes to maximally strengthen muscles used to develop power and control in their individual sport In addition to strengthening the core muscles of the trunk and hip, the Power Arc Exercise Device also provides strengthening for the arm and hand muscles.