Healthcare communication is an area that offers great benefits in the promotion of preventive health behavior. Given that physical activity can significantly reduce risk factors that are associated with major chronic diseases, it is paramount to examine the promotion of physical activity through appropriate message designs. This study employs priming theory, the framing postulate of prospect theory, and the source factor to examine effective message design in the promotion of exercise. Overall, it shows that semantic consistencies between prime and frame, as well as frame and source, are more conducive to message persuasion. Hence, the contention of framing by the type of health behavior (Rothman & Salovey, 1997) is moderated by prime and source factors.