With a bench, a rack and a barbell you can quickly improve your overall strength in your chest, back, shoulders and arms as the barbell allows you to lift heavier than with other equipment. Depending upon the bench position you can alter the muscles that are worked the most. Flat bench press is the good all rounder for improving strength across the muscle groups. The incline press targets the upper pecs and anterior deltoids more whereas it's the opposite with the decline press targeting the lower pecs more but neither will allow you to lift as much as with the flat bench press.