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There are plenty of workout routines for overall chest development, helping you to build a defined and bigger chest.
Cable crossovers, dumbbell flyes, diamond push-ups, and dumbbell bench press are some of the best chest exercises worth incorporating into your upper body strength training routine.
The entire chest itself is made up of four muscles; the pectoralis major, pectoralis minor, the subclavius and the serratus anterior. Collectively, they are responsible for movement of the arms.
When it comes to working out, most focus is placed on the pectoralis major which is the largest and most prominent of the four chest muscles.
For someone wishing to improve the aesthetic of their chest, this is likely to include focusing on definition of the inner chest muscles (the inner part of the pectoralis major).
However, it’s worth noting that the muscle fibers of the inner chest cannot be isolated.
Instead, there will be a number of suitable exercises that can better activate the inner pecs, helping to improve definition and the appearance of muscle striations.
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However, to improve the definition and depth of the inner chest area, you’ll also need to implement exercises that build thickness to the entire pectoralis major.
By improving muscle size and thickness will automatically result in more of a concave appearance of the inner chest.
For muscle striations to pop, this is less down to lifting heavy weights and more to do with diet. In other words, you’ll need to reduce your body fat which will improve the appearance of the chest muscle fibers.
In this article, we’ll look at the function of the chest along with several exercises to help activate the inner chest muscles.
Chest Muscle Anatomy
As stated above, the chest comprises of four distinct muscles and it’s the pectoralis major that gives the chest its appearance and size.
This is the large, fan-shaped muscle that originates from the center of the rib cage and inserts at the anterior surface of the upper end of the humerus.
Together, the muscles of the chest are responsible for providing shoulder stability and allowing for full range of motion of the arms.
Strengthening the muscles of the chest can improve posture and improve strength to the upper back helping to alleviate conditions such as back pain.
Below we look at each of the chest muscles and their primary functions.
The pectoralis major, the largest of the chest muscles, is made up of two heads: the clavicular head and the sternocostal head.
It’s a powerful muscle with a main function of bringing the arms up and together in front of the rib cage, as if hugging someone. Let’s look at each head in turn:
The sternocostal head, also called the “lower chest,” is the largest head of the pectoralis muscles. And this is where you’ll find the inner chest.
The sternocostal head starts at the anterior outer part of the sternum and the aponeurosis and inserts laterally to the intertubercular sulcus.
Most of your arm abduction and rotation is powered by the sternal head.
Technically speaking, the inner chest is the area of the chest closest to the sternum and the center of the chest.
Exercises that target the inner chest also develop the overall chest muscles.
The clavicular head, or “upper chest,” originates anteriorly from the medial half of the clavicle (the collarbone) and extends down to the humerus.
It is the smaller part of the pectoralis major muscle, making up approximately 20% of the chest’s total mass.
The clavicular head helps support the lower chest, although its primary function is to promote arm flexion (lifting the arm upward).
Some of the best exercises for building a strong upper chest include incline presses and an incline dumbbell fly.
The pectoralis minor sits directly beneath the pectoralis major muscle.
It’s a small muscle that originates from the anterior surface of the ribcage and inserts at the medial surface of the coracoid process of the scapula.
The primary role of the pectoralis minor is to stabilize the scapula (shoulder blade) and allow for a full range of motion of the shoulder joint.
The serratus anterior is a muscle with a serrated like appearance, hence its name.
It originates from the outside surface of the rib cage and continues around the body posteriorly connecting to the anterior surface of the medial border of the scapula.
It provides stability to the scapula essentially attaching it to the rib cage. Its main function is protraction and upward rotation of the scapula.
The subclavius is the smallest of the four chest muscles and originates from the first rib (top of the rib cage) and extends upwards inserting into the inferior (underside) of the clavicle.
Its function is to depress the clavicle inferiorly and anteriorly providing support to the clavicle when the arms and shoulders move.
Best Exercises For Your Inner Chest Workout
The below suggested exercises are some of the most effective for developing your inner and overall pectoral muscles.
As mentioned, you can’t isolate specific sections of a particular muscle and if you want to see the best results, a varied chest workout is essential.
For the best inner chest workout incorporate as many of these exercises into your routine.
The pectoral muscles respond well to variety.
Plus, muscle growth and strength gains are more likely to occur when the exercises are varied.
Flat Bench Dumbbell Fly
The flat bench dumbbell fly is a compound exercise that will target multiple muscles including the inner chest.
This movement will help you build a strong chest and allows for full range of motion.
You’ll need access to a flat bench and a pair of dumbbells. To keep to good form, don’t go too heavy with the weights.
How To Perform A Flat Bench Dumbbell Fly:
- Take hold of your dumbbells and sit on the edge of a flat bench.
- Lie back and hold the dumbbells out in front of you and over the lower part of your chest, your palms should be facing inwards with your elbows slightly bent (this keeps pressure off of the elbow joint).
- Keeping your feet flat on the ground, slowly lower the dumbbells out towards your sides. Make sure to keep your wrists straight with elbows slightly bent throughout.
- Once your elbows have reached a point of just underneath your back, slowly bring your arms back up to the starting position whilst squeezing the chest muscles.
Close Grip Push-Up
If you want a firmer chest, try the close-grip push-up.
How To Perform A Close Grip Push Up:
- Assume a plank position and position your hands just underneath your chest and inside shoulder width apart.
- Keep your back straight and core tight throughout the movement. This is your starting position.
- Slowly lower your body just as you would with a regular push-up whilst keeping your elbows tight to your torso as possible.
- Work to keep your forearms as close to perpendicular as possible. Don’t flare your elbows.
- Push back up to the starting position.
If you find the movement too difficult to begin with, rest on your knees instead of your toes.
The diamond push up, also known as triangle push up, is a variation of the standard push up.
This exercise increases your shoulder strength, core strength, chest muscle activity, and tricep activity.
Here’s How To Perform Diamond Push Ups With Proper Form:
- Put your index fingers and thumbs together to form a triangle shape.
- Spread your fingers on the ground and get into a plank position, just like you would in a regular push up. Keep your back straight and core engaged throughout the exercise.
- Now, slowly lower your body to the floor until your chest touches your hand. Keep your elbows close to your body, and don’t let them flare out.
- Press your body back up and return to the starting position.
Middle Chest Cable Fly
Cable flyes are one of the best exercises for working the entire chest area.
Cable exercises maintain tension throughout the range of motion, allowing for continuous muscle stimulation.
You’ll need access to a cable crossover machine.
How To Perform A Middle Chest Cable Fly:
- Select your chosen weight and then position the pulleys on both sides around hip height.
- Hold on to each attachment and stand in the center and take a step forward, so your arms are pulled back yet slightly bent forward at the elbow.
- Stagger your feet so one foot is in front of the other. Maintain a bend to the front knee.
- Keeping your chest up and back straight, bring your palms together.
- At peak contraction, your arms should be out in front of you, palms facing inwards with your arms just below chest height.
- Squeeze the chest muscles and hold for a second before slowly allowing your arms to return to the start position.
- Don’t allow your arms to go too far back as this could put stress on the shoulder joints.
Decline Cable Pullover
The decline cable pullover is a great alternative to dumbbell pullovers allowing for a stricter ranger of motion and excellent recruitment of the inner chest muscle fibers.
Both chest and back muscles are recruited during this exercise.
How To Perform A Decline Cable Pullover:
- Start be setting a decline bench press in front of a cable machine. Ensure the pulley is positioned at the bottom of the machine and attach a rope attachment.
- Lie on the bench and lock your feet under the rollers for stability.
- Reach back and take hold of the attachment with both hands.
- Keeping a slight bend at the elbows, pull the attachment overhead and down.
- Squeeze the chest muscles together and hold for a second before slowly returning your arms back to the starting position.
The plate press is one of the simplest and most effective exercises for developing the inner chest, shoulders, triceps, and core.
You’ll be pressing your palms together and into a plate for this exercise.
You are going to push the weight together, not grab them.
Whilst pushing, you are going to flex your chest and hit the middle of your pec.
If you’re new to this exercise, start with a lighter weight.
Here’s How To Perform A Plate Press:
- Grab a weight plate and sit on an adjustable weight bench. Ensure the back pad is set to around 30 degrees (or flat if you prefer).
- Lay back on the bench whilst holding the plate.
- Keep your elbows tucked into your body, and ensure your feet are firmly on the ground.
- Push the plates together and move them up and down. You should feel this down the middle of your chest.
- Exhale on the way up and inhale on the way down. Keep your core nice and tight throughout.
- Your hands should be centered on your chest and belly button as you lift and lower the plates.
- For the inner chest, it’s best to go slow and controlled with plenty of high reps.
How to Avoid Injuries During Your Inner Chest Workout
When working out the inner chest, there are a few ways to prevent injury. They include:
Select the Right Exercises
Choosing exercises that help you get in shape while maintaining your fitness level is crucial.
If the movement is too advanced, you won’t be able to maintain proper form.
As with any exercise, correct form is crucial for obtaining the most benefits from the exercise whilst limiting the chance of injury.
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On the other hand, if the workout is too easy, it won’t challenge you enough to see improvements.
Trying out different exercises can help you find the best ones for developing your chest muscles and strength.
Select the Right Weight Load
Whether you opt for a weight plate, dumbbells, or a barbell, choosing a weight you can lift whilst maintaining form for the whole set is important.
A challenging, but manageable, weight will help you get the most out of your workout without other muscles taking over during the exercise.
If you’re trying to get through a particularly difficult work set, you might compromise your form to complete the required number of repetitions.
Poor technique can result in muscle strain and injury.
Keep Workouts Varied
Keep exercises varied when working certain muscle groups, including the chest.
Not only does this ensure you hit every part of the muscle (especially important with larger muscles such as the pectoralis major) it means you’re less likely to fatigue muscles.
Training over-tired muscles can result in injury.
Building a strong and well-developed chest means you have to incorporate a wide variety of exercises to see best results.
As you’re not able to isolate parts of a muscle group, it’s necessary to use a number of compound movements along with chest isolation exercises to have the best chest of targeting the inner chest.
Don’t forget, if you want to see the muscle fibers popping through the skin, you’ll need to make sure your diet is on point to strip away body away.
Also, remember that the benefits of a strong chest go well beyond visual appeal; they also improve posture and make many day to day activities much easier.