One of the best upper-body exercises: Performed face down on the floor, palms against floor under the shoulders, toes curled upwards against the floor. The arms are used to lift the body while maintaining a straight line from head to heel. The arms should go from fully extended in the high position to nearly fully flexed in the low position, while the subject makes sure to avoid resting on the floor. Resting is only done in the high position of the exercise. Chest, shoulders, and triceps are trained with this exercise.