So right away Claude introduced Henri to his famous "moon " bench and proceeded to teach him his first Push-Pull Super-Set consisting of the wide grip Straight-Arm Pullover ( the "pull " part of thePush-Pull Super-Set ) which dramatically widens the rib cage and strongly affects the muscles of the upper back and chest , and the collar-to-collar Bench Press which specifically works on the chest to build those wide , Reeves-type "gladiator " pecs , while stimulating the upper lats and frontal deltoids .