Decline pushups are an upper body exercise that targets the chest, shoulders, and triceps. Begin by placing your feet on an elevated surface such as a bench or step, with your hands on the ground. Position your hands shoulder-width apart and keep your body in a straight line from head to heels. Lower your body until your chest nearly touches the floor, keeping your elbows at a 45-degree angle. Press back up to the starting position. Maintain a tight core throughout to prevent sagging or arching of the back.