Best Exercises for the Trapezius Muscle

In this article we will discuss the following (click any to jump to that section):

• Scapulothoracic Muscles and Pain
• Biomechanics Review: Scapulothoracic and Glenohumeral Joints
• Anatomy of Trapezius
• From Biomechanics to Exercises
  • Upper Trapezius
  • Middle Trapezius
  • Lower Trapezius
• Choosing the Best Exercise
• [Video] Shoulder Impingement

To start this Evidence-Based Strength Training Series, we’ll take a look at the often-neglected scapulothoracic muscles, their functions and the best exercises to recruit them.

Scapulothoracic Muscles and Pain

Typically, when clinicians consider how to manage upper quarter pain, they’re careful about using local exercise and manual therapy. However, with a proper movement assessment or regional interdependence philosophy, clinicians recognize that impaired scapulothoracic muscles often contribute to pain in distal or proximal joints. Weakness or poor neuromuscular control of the periscapular muscles has been implicated in subacromial impingement^4,18, lateral epicondylalgia^2,7,12, cervicogenic headache¹⁰, and neck pain^3,16.

In a prospective cohort study by Clarsen et al, scapular dyskinesis led to an 8.4 times greater risk of shoulder injury during an elite male handball season.⁶ Further, Lawrence and colleagues found that shoulder pain due to subacromial impingement significantly reduced scapulothoracic upward rotation at lower angles of humerothoracic elevation and sternoclavicular posterior rotation throughout humerothoracic elevation.¹¹

Biomechanics Review: Scapulothoracic and Glenohumeral Joints

• In humeral elevation, the scapula rotates up 1° for every 2° of elevation until 120° are achieved. Afterwards, the scapula rotates 1° for every 1° of elevation until the arm reaches maximal elevation.
• The scapula typically tilts posteriorly between 20° and 40° in the sagittal plane.
• The scapula rotates externally between 15° and 35° in the transverse plane.¹⁷

These joint movements rely on coordinated and balanced work from several muscles: the trapezius, serratus anterior, levator scapulae, rhomboid, and pectoralis minor muscles.

Anatomy of the Trapezius

The trapezius starts at the medial third of superior nuchal line, external occipital protuberance, nuchal ligament, and the spinous processes of C7-T12 vertebrae with a distal insertion at the lateral third of clavicle, acromion process, and spine of scapula.

Trapezius is divided into 3 distinct portions:

• Upper trapezius (UT) providing scapular elevation
• Lower trapezius (LT) providing scapular depression
• Middle trapezius (MT) causing scapular retraction

The UT and LT together rotate the glenoid cavity superiorly, which is often a problem for individuals with shoulder impingement or pain.¹¹

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From Biomechanics to Exercises

Upper Trapezius

Primary function: scapular elevation

The highest Maximal Isometric Voluntary Contraction (MVIC) is achieved with elevation of scapula. During scapular abduction, UT activity progressively increases from 0° to 60° and from 120° to 180° of abduction.¹

Researchers have found that the highest electromyographical (EMG) activity occurs in the following exercises:

• unilateral shoulder shrug⁹
• rowing¹⁴
• scaption⁸
• shoulder abduction in the scapular plane above 120° ⁹

Because UT weakness is rather rare (unless secondary to neurological involvement), it seldom deserves attention when treating the upper quarter pain. Instead, clinicians focus on strengthening middle and lower trapezius and normalizing the activation ratio of UT to the lower two trapezius (MT and LT).

[Table] Click to see MVIC values for UT exercises

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Middle Trapezius

Primary function: scapular retraction

MT is often activated with scapular retraction. The highest MVIC for the MT has been recorded during the following exercises:

• horizontal abduction¹⁴
• prone full-can⁹
• horizontal abduction with external rotation¹⁴
• scaption⁸

As the UT often compensates for a weak MT or LT, it may be beneficial to use exercises with a good UT:MT ratio such as:

• side-lying forward flexion
• side-lying external rotation
• prone shoulder extension⁵

[Table] Click to see MVIC values for MT exercises

Lower Trapezius

Primary function: scapular depression

Because LT impacts scapular upward rotation, external rotation, and posterior tilt, its strengthening yields better results than that of UT and MT.¹⁷

This connection has been confirmed by many studies of the LT weakness and its association with pain.

Numerous studies also looked into maximal EMG activity of the LT during upper extremity strengthening and determined that MVIC has been significantly higher during the following exercises:

• Arm raised overhead in line with the LT muscle fibers⁹
• External rotation at 90° of abduction^9,15
• Horizontal abduction with external rotation⁵
• Prone shoulder abduction⁵

While high MVIC is a good criterion for choosing exercises, an optimal UT:LT ratio can be even better. Being the primary actors in upward scapular rotation, UT and LT should make adequate and relatively equal contributions to maintain normal biomechanics. A study by Cools and colleagues determined that the following exercises have the best UT:LT ratios:

• Side-lying forward flexion
• Side-lying external rotation
• Horizontal abduction with external rotation⁵

In a similar study by McCabe et al., the following exercises activated the LT over the UT:

• Seated press-up
• Unilateral scapular retraction
• Bilateral shoulder external rotation¹³

[Table] Click to see MVIC values for LT exercises

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Choosing the Best Exercise

Although these studies give us a glimpse into properly selecting exercise, very few exercises have been or will ever be studied. When choosing an exercise for your patient, be sure to consider:

• the biomechanics of the movement
• current evidence for or against the exercise
• your patient’s presentation, and goals for treatment

The trapezius is an important piece of the puzzle, but the serratus anterior, rhomboids, and levator scapulae also contribute to upper quadrant pain.

For more information on treating shoulder dysfunction, check out Eric Hegedus’s course Evidence-Based Treatment of the Shoulder: An Update.