Muscles Used in the Bench Press

There’s a reason that the bench press is one of the most popular upper body exercises there has ever been! The bench press is a compound exercise working all of the pushing muscles in one go. The bench press is one of the exercises in the official lift list for the level 2 fitness instructor course accredited by all UK awarding bodies. You might also be aware that Monday is international chest day in every single gym around the world! Personal trainers who know how to teach; coach, and modify this exercise will be able to help a wider range of client groups. To be able to do this, it is important for all fitness instructors and personal trainers to understand the muscles involved in this game changing exercise.

Muscles of the Bench Press

Pectoralis Major The muscle that is visibly located in the centre of the chest over the ribs. The 4 main joint actions include flexion of the humerus (underhand throwing), adduct the humerus (flapping the arms), internally rotates the humerus (arm wrestling), and horizontal flexion (clapping the hands with arms extended).

Pectoralis Minor A thing flat muscle that is located under the pectoralis major. Pectoralis minor plays a role in stabilising the shoulder as it inserts onto the scapula (involved in the shoulder girdle). The primary joint actions are; depression, abduction, protraction, and internal rotation.

Anterior Deltoid The front part of the shoulder muscle, one of the three heads of the shoulder that give it the “capped look”. The anterior deltoid assists with shoulder flexion andassists the pectoralis major.

Triceps Brachii The muscles located on the back of your upper arm. The main job of the triceps brachii is elbow extension (straightening the arm) in pressing movements.

Muscle Fascicle Arrangement

The bench press has a number of variations and allow the pectoralis major to be developed in a number of ways. The pectoralis muscle fibres are organised in a convergent pattern. This is because the muscle spreads over a wide area and inserts into one single tendon. If you imagine a wide fishing net being tossed out into water, it will cover a large area. When the fisherman pulls the net in, they pull from one single point, pulling the net in tight (concentric contraction). The alignment of the muscle fascicles (bundle of muscle fibres) allows the pectoralis major to be developed in different ways.

Fascicle arrangement of Pectoralis Major.

Structure of Skeletal Muscle

Adaptations of the Bench Press

Incline Bench Press: This variation targets the fibres of the upper chest on the clavicular origin. The head is above the hips at a 30-45 degree angle. In this position the anterior deltoid will contract more powerfully.

Decline Bench Press: Targets the lower portion of the chest at the sterno-intercostal origin, the head is below the hips at 15-30 degrees and no more. The latissimus dorsi will contract more forcefully in this position.

Wide Grip Bench Press: Focuses more on the pectoralis major and less on the triceps brachii.

Narrow Grip Bench Press: Switches more focus to the triceps brachii and and less on the pectoralis major.

Dumbbells: Will require greater levels of symmetrical neuromuscular coordination as both the left and right side will work independently.

Barbell: Provides the next step up from a resistance machine, left and right sides can draw strength from each other as they are linked by the bar. Equal force must be applied to avoid over and underdevelopment of the left or right side.

Power bands: Adding power bands is an excellent variation. The elastic properties of power bands keep the pectorals and working muscles under constant tension during concentric and eccentric contraction. Power bands will also add additional (variable resistance) as the band is stretched and as it returns to its normal length.


Principles of balanced programming refers to equal development. The pectorals are an anterior muscle. The opposing back muscles are posterior muscles. To avoid rounding of the back (lengthening and weakening the muscles), causing them to be phasic (long and weak). We must train the back muscles, specifically the middle trapezius; rhomboids, and muscles of the rotator cuff. This will avoid shoulder impingement and the development of poor posture, bringing the spine out of alignment and causing possible back pain.

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