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Here you will find an article on one exercise (new one every month). With a detailed analysis of the muscles used during the exercise and a informative description of how to both perform and assist in the actual performance of the exercise.

A full library of all previous exercises can be found at members online under the sub menu

Exercise: Dumbbell Flye

Client Instruction

Starting Position

1. Grasp a dumbbell in each hand and lie on a bench in a supine position
2.  Anchor your feet so that they are flat and placed firmly on the floor or raised platform
3.  Contract your abdominals to support your low back

Down  Phase

4.  Hold the dumbbells directly above your chest in a neutral grip, with your arms almost straight
5. From this starting position, inhale and slowly lower the dumbbells towards the floor
6.  Maintain a relatively fixed straight arm position so that the dumbbells follow a wide arc perpendicular to the bench
7.  Lower the dumbbells as far as comfortably possible without lifting your shoulders or back off the bench

Up Phase

8.  Pause at the bottom of the exercise and then return your arms back to the starting position, exhaling as you lift the weight
9.  As you press the dumbbells above your chest keep your elbows to the side of your body so that they are perpendicular to your trunk

Muscle Analysis Chart - Dumbbell Flye (Up Phase)

Muscle Analysis Chart - Dumbbell Flye (Down Phase)*

*Down Phase

In the down phase of the exercise the weight is slowly lowered with gravity. The muscles that concentrically contracted to lift the weight are the same muscles that are eccentrically contracting to lower the weight.

General Kinesiological Analysis

In the up phase of the dumbbell fly, the shoulder joint horizontally adducts to lift the weight above the chest. This is caused by the concentric contraction of the pectoralis major, anterior deltoid, coracobrachialis and the short head of the biceps brachii. Assisting in lifting the weight is the serratus anterior and pectoralis minor contracting concentrically to abduct the scapula. The elbows are held in a static position by the co-contraction of the triceps and anconeus and the biceps brachii, brachialis, brachioradialis and the pronator teres.

Advanced Kinesiological Analysis

When a dumbbell chest fly is performed, the pectoralis major and the anterior deltoid are the prime movers. The horizontal adduction movement of the shoulder joint is the result of both sections of the pectoralis major contributing to lifting the weight. The coracobrachialis and the biceps brachii contribute to the movement by acting as assistant movers. The co-contraction of the biceps, brachialis, brachioradialis and pronator teres in concert with the triceps and the anconeus maintains the elbows in a static position, which allows the chest muscles to assume full responsibility for the movement. The dumbbell chest fly allows the dumbbell to be lowered to a deeper position than the barbell bench press. Providing the dumbbells are not lowered beyond the chest height, the shoulder joint can be moved through a greater range of motion creating a greater load on the pectoralis major and anterior deltoid. For the shoulder joint to move into horizontal adduction the scapula must be drawn into abduction, caused by the concentric contraction of the serratus anterior and the pectoralis minor.

As the pectoralis major and anterior deltoid are contracting in horizontal adduction, they are also causing a secondary medial rotation due to their angle of pull on the humerus. To prevent this from happening, the infraspinatus and teres minor statically contract to neutralize this unwanted movement. In the same vein, the serratus anterior and the pectoralis minor combine to cause abduction of the scapula while neutralizing the additional unwanted upward and downward rotation.

In both the barbell bench press and the dumbbell chest fly, the scapula abducts at the same time that the shoulder joint is horizontally adducting in order to lift the weight in the up phase of the exercise. This is an example of dynamic stability, which occurs when the origin of the muscles causing the movement is moving in the same direction as their insertion. For example, the origin of the deltoid is the anterior clavicle, acromion and the spine of the scapula. Its insertion is on the deltoid tuberosity on the humerus. During the barbell bench press and the dumbbell chest fly the anterior deltoid contracts concentrically to cause the humerus to move into horizontal adduction. At the same time, the scapula begins to abduct, moving in the same direction as the humerus. The stabilizers in this exercise are the abdominals and the spinal extensors.    

Exercise Variations

Variations of both the barbell bench press and dumbbell chest fly have been prescribed to change the angle of the exercise in order to recruit different aspects of the muscles reported. In the incline bench press and the incline dumbbell press the bench angle is changed from a flat position to approximately 15-30 degrees. At this angle there is reportedly a more significant contraction of the clavicular pectoralis major and the anterior deltoid. Below this angle range, the full pectoralis major, anterior deltoid and coracobrachialis will contract to cause the movement. In a decline bench press, decline dumbbell chest press and decline chest fly the client’s head is now lowered below their feet to an angle of approximately 20-25 degrees. The purpose of this exercise is to create a greater overload on the sternal portion of the pectoralis major. The anterior deltoid will also contribute to the exercise.

Cable Pulley Variation

The client lies in a supine position on a bench or stability ball located between a low cable/high cable cross over pulley machine. From this supine position, the client reaches down by opening their chest and grasps the handles on either side of the low cable pulley. After grasping the handles on either side of the machine, the arms are maintained in a semi flexed/extended position as the shoulder joints are horizontally adducted. As the weight stacks are lifted on either side of the machine the handles cross over at their highest point above the client’s chest. Once in this position the weight is slowly lowered back to the starting position through the lifting arc. 

Stability Ball Exercise Variation

The client lies in a supine position on top of a stability ball. The client rolls the stability ball forward so that the upper back and shoulders are in contact with the ball. The client contracts their gluteals and lower back to form a bridge with a 90 degrees angle at the hip joint and the knee joint. The client holds the dumbbells directly above their chest in a neutral grip, with their arms almost straight. From this starting position, the client inhales and slowly lowers the dumbbells towards the floor while maintaining a relatively fixed straight arm position. The dumbbells follow a wide arc perpendicular to the stability ball. Once the dumbbells are dropped below the shoulders the pectoralis major, anterior deltoid, coracobrachialis and the biceps contract concentrically to horizontally adduct the shoulders back to the starting position.

© 2007 Fitness Institute Australia

Disclaimer: No responsibility is accepted for any loss or damage suffered as a result of the use of the above information
or any reliance on it. Users should satisfy themselves as to their own or clients medical and physical condition before adopting/using
the information or recommendations made. No responsibility or liability is accepted for any loss or damage suffered
by any person as a result of adopting the above information or recommendations.

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