When putting together a workout routine, it’s very important to know how your shoulders are built and how they work.
The shoulders are composed of three muscle heads: the front (anterior) head, the middle (lateral) head, and the rear (posterior) head.Every head of the shoulder has its own function.
Anterior (front) head of the shoulder is used in pushing movements and gets heavily worked when you do incline and flat bench presses. The lateral head also gets involved in pushing movements to a lesser extent. Isolation movements for the front shoulder include front raises.
Lateral (middle) head of the shoulder is responsible for moving the arms sideways. It gets worked from shoulder presses (along with the front head). This is the part of the shoulders you need to concentrate on when training to build wide shoulders. Isolation movements for the side head include side dumbbell raises and wide grip upright rows.
Posterior (rear) head of the shoulder is used in pulling movements (larger part of the pulling is done by the back muscles though) and gets heavily worked when you do all kinds of rows and deadlifts. Isolation movements for the rear head include bent over raises.
Bodybuilders often complain that their shoulders don’t grow or lag behind their other body parts. That’s because shoulders are a small muscle group and often an overtrained one. They literally get worked every time you train your upper body. So if you don’t want to intentionally overtrain them, you could train front delts along with your chest, rear delts with your back and add an exercise for the middle head of the shoulders. A separate shoulder day is probably too much stress for the deltoids. Remember, keep it simple.