Chest workouts typically fall into four categories — inner, outer, upper, and lower. In each category, a different portion of the chest muscles are targeted to achieve a maximal result in all areas. All of these types of chest workouts can include similar exercises, which will have simply altered grip or body positions in order to stress a different muscle group or portion of muscle. Chest exercises come in two basic types — push, as with a bench press, and pull, as with a fly.
As an example, consider the bench press. At its most basic level, it involves lying on a flat bench, with the buttocks touching the bench at all times, and the feet flat on the floor. The arms are extended out to the sides of the chest and the elbows are kept at a 90° angle to the forearms. A bar above the chest, typically weighted down with plates on each end, is then gripped and raised off of its resting position. The bar is lowered to almost touch the chest and is then raised again until no more repetitions can be completed.
When the grip on the bench press bar is kept just wider than shoulder width, the pectoralis major chest muscles will be exercised. As the hands are brought closer together, the focus of the exercise will shift toward the inner portion of the pectoralis muscles, as well as the triceps. Work on this area is what will eventually produce the distinct line of definition between the two pectoralis major muscles.
A bench press can also be used to work the upper and lower portions of the chest muscles, by either inclining or declining the bench. This allows for the chest muscles to receive an all-over workout, leading to a more consistent shape. These rules also apply to other chest exercises, such as push-ups. Wide push-ups, where the hands are out much farther than shoulder width, will result in a working of the outside edge of the chest muscles. Decline push-ups, accomplished by placing the feet on a table or chair and then doing the exercise with the hands on the floor, will tax the lower chest muscles.
An athlete will cycle through various types of chest workouts in order to best maximize muscle gain. Many workout programs involve several variations on a chest exercise in the same day, allowing for an overall conditioning. It is advisable, however, to allow a rest period of at least several days before another chest workout, to allow the muscle tissue time to heal and rebuild.
Other methods are also employed by athletes to vary their chest workouts. One option is to do chest exercises with reduced stability, such as on an exercise ball or with the legs up. This reduces the amount of weight lifted, but increases the use of stabilizer muscles around the chest. As with any exercise routine, varying chest workouts typically leads continual muscle gain.