What is scapular retraction during a chest press?

Scapular Retraction During Chest Press

Scapular retraction during a chest press is the active pulling back and squeezing together of the shoulder blades (scapulae) toward the spine, creating a stable base for the shoulders and optimizing force transfer through the upper body during the pressing movement.

Biomechanical Definition and Purpose

Scapular retraction involves the coordinated activation of the middle trapezius and rhomboid muscles to draw the scapulae posteriorly (backward) and medially (toward the midline of the spine) 1. This movement pattern creates several key mechanical advantages:

• Stabilizes the glenohumeral joint by positioning the scapula to provide a stable platform for the humeral head, reducing unwanted translations and improving force transmission 2
• Optimizes subacromial space by increasing the distance between the acromion and humeral head, which reduces impingement risk during pressing movements 3
• Enhances rotator cuff function by allowing the infraspinatus and other rotator cuff muscles to generate force more effectively when the scapula is retracted versus protracted 2

Muscle Activation Pattern

The primary muscles activated during scapular retraction are:

• Middle trapezius generates the highest activation levels (30.5% to 51.6% of maximal voluntary isometric contraction) and is the primary retractor muscle 4
• Lower trapezius contributes to retraction while also controlling scapular upward rotation and posterior tilt 4
• Rhomboids work synergistically with the trapezius muscles to pull the scapulae medially 1
• Upper trapezius shows lower relative activation compared to middle trapezius during proper retraction, with optimal ratios occurring at 0° shoulder abduction 4

Proper Execution During Chest Press

The scapular retraction technique during chest press involves:

• Initial positioning: Pull the shoulder blades down and back before initiating the press, creating a "shelf" against the bench 1
• Maintained throughout movement: Keep the scapulae retracted during both the eccentric (lowering) and concentric (pressing) phases of the lift 2
• Clavicular positioning: Retraction also involves clavicular retraction and depression, which accompanies the scapular movement 1
• Scapular external rotation and posterior tilt occur naturally with proper retraction, further optimizing shoulder mechanics 1

Clinical Significance

Scapular retraction during chest press provides important protective and performance benefits:

• Reduces impingement risk by maintaining adequate subacromial space width compared to protracted scapular positions 2
• Optimizes force production from the rotator cuff muscles, particularly the supraspinatus, which generates more effective force when the scapula is retracted 2
• Prevents anterior shoulder instability by maintaining proper scapulohumeral rhythm and preventing excessive anterior translation of the humeral head 2

Common Errors to Avoid

• Allowing scapular protraction (shoulder blades spreading apart and moving forward) during the press reduces stability and increases injury risk 2
• Excessive upper trapezius dominance without adequate middle trapezius activation creates unfavorable muscle ratios and poor scapular control 4
• Loss of retraction at end-range of the press when fatigue sets in compromises shoulder mechanics 1

Relationship to Shoulder Rehabilitation

The scapular retraction pattern used in chest press mirrors therapeutic exercises:

• Progressive loading from 40-50% of maximal voluntary contraction optimally activates middle trapezius, lower trapezius, and infraspinatus without excessive upper trapezius activity 5
• Middle trapezius activation correlates directly with improved acromiohumeral distance during shoulder movements, making retraction exercises valuable for shoulder rehabilitation 3
• Scapular retraction strengthening addresses the kinetic chain dysfunction commonly seen in shoulder pathology, particularly in overhead athletes 6, 7