Fitness enthusiasts often overlook the inner chest muscle groups in lieu of building the more obvious and aesthetic outer chest groups. From both a functional and aesthetic angle, isolating and improving the inner chest muscles is essential.
If you have ever wondered why your outer chest lines are adequately defined, but the “ridge” in the middle over your sternum is not, it is likely that the inner chest muscles have not been targeted.
In this article, we cover the importance and role of the inner chest and some basic exercises to target these elusive muscles. As always, we provide our readers with bodyweight exercises and added weight exercises to ensure maximum accessibility.
The Inner Chest
In defining the “inner chest, “ we draw attention to the pectoralis major, the largest muscle in the chest area. Its sheer size dictates the well-known fact that every chest exercise you do will be targeting both the inner and the outer chest.
Targeting the inner chest is often less about the exercise itself, but how it is conducted. Where the two pectoralis major muscles meet at the sternum, there is a vertical column that runs up to the base of the neck and shoulders.
This column is what needs to be “defined” for there to be a clear separation of the two pectoralis major muscles.
The pectoralis major muscles are capable of a full range of motion. Yet, each direction of movement (horizontal, vertical, up, and down) builds a different facet of the muscle and allows us to target either the outer or inner chest.
For the inner chest, it is well documented that two main types of “motion” are most efficient when defining the aesthetic borders. These two types are lifts and forward crossing of the midline (i.e., the arms come together or cross at your midline).
While there are exercises that are better than others for the inner chest, most chest exercises can be adapted to target the inner or outer chest.
Bodyweight Exercises for the Inner Chest
As always, we like to give our readers the chance to start slowly and progress safely. As we are also firm believers in mobile fitness and bodyweight exercises, we will begin with some “weight-free” exercises that can be performed anywhere.
There is no better place to start then with the basic chest exercise that has been tried, tested, and proven superbly effective. There are plenty of derivatives of the push-up, but it is essential to focus on technique and positioning when targeting the inner chest rather than a labeled exercise.
When trying to build the inner chest, your hands should be positioned closer together rather than further apart. While most standard push-ups call for the hands to be under your shoulders, bringing them closer together will emphasize the inner chest.
Diamond pushups are a perfect example, with your index and thumb fingers forming a diamond directly under your sternum.
Next time you drop down for 20 reps, try doing 10 with arms close together (diamond) and 10 with your hands wider than your shoulders. You should notice the difference between working the inner and outer chest with each of these exercises.
The Valslide fly is a great litter bodyweight exercise to work the inner chest. This exercise is more easily performed on a smooth surface such as a tile or wood floor and can be more comfortable by putting towels under each elbow. If you find yourself with access to carpet only, you can complete the exercise using sliders.
Starting in a plank position on your elbows, find the balance point by engaging your core and comfortably rooting your elbows and forearms on the ground under your shoulders. Splay your elbows out to your sides and lower your chest to the ground. Bring your elbows back together to raise your body back up to the original position.
Working the Inner Chest with Weights
For those who have access to free weights or a gym, these exercises will include additional weight in order to target the inner chest.
Hammer Squeeze Press
This specific exercise focuses both on a vertical press with horizontal adduction, two movements that do wonders for the inner chest. To complete this exercise correctly, you will need two dumbbells and a medicine ball.
Start on an incline bench with a dumbbell in each hand, and squeeze the medicine ball between the two dumbbells. While keeping the dumbbells parallel to the chest the entire time, press straight up while continuing to squeeze the medicine ball. You will feel the burn on the inner chest almost right away.
This derivative of the squeeze press uses a weight place to be held firmly in the middle of the chest. Using the palms of each hand, push the chest together to keep the plate secure, lie back, and line up the plate over the top of your sternum.
Keeping the squeezing pressure through the chest, press the plate up slowly, and bring it back down in a controlled manner.
Start with low weight and high reps for this one until you’re comfortable with the movement.
Close Grip Dumbbell Bench Press
This dumbbell press requires only one dumbbell to be gripped in a diamond shape with both hands. Similar to the plate-press mentioned previously, it’s best to use a flat bench to allow the elbows to break the lateral plane and deepen the exercise.
You hold the dumbbell similar to how you would grip it for a behind-the-head tricep press.
You can almost imagine this exercise as a diamond pushup in reverse, pressing the dumbbell away from the body and lowering it slowly back to the chest.
Exercises to build the inner chest can be easily incorporated into any existing chest workout. By focusing on form and technique, familiar exercises can be slightly tweaked to target the inner pectoralis major and create that clear divide.
By focusing on movements that both press up and squeeze in, you can build both functionality and aesthetic to your chest.