Trapezius

Reading time:

The trapezius originates at the midline of the body, from the higher cervical vertebrae to the lower thoracic vertebrae, and inserts on the lateral third of the clavicle, as well as on the acromion and scapula spine.

Given its many mechanical lines of action, the trapezius is likely to be involved in many functions. It seems to function primarily as a shoulder girdle elevator, scapular upward (and downward) rotator, and shoulder retractor.

The trapezius muscle includes three regions that vary in architecture and size. The upper and middle fibers display greater physiological cross-sectional area and muscle thickness, respectively, compared with the lower fibers. The fibers attaching to the acromion display the longest fascicle lengths. The upper fibers attaching to the clavicle are more heavily pennated than the fibers attaching to the acromion.

Strength athletes are likely to display a greater proportion of type II muscle fibers than type I muscle fibers in the trapezius, while non-strength athletes are more likely to display a mixed muscle fiber proportion. This may imply that training with higher speeds and heavier loads are more beneficial for training the trapezius in strength athletes.  

During the deadlift, it appears that trapezius muscle activity is greater with increasing load while deadlift type or grip technique has no effect. Upper trapezius muscle activity displays superior muscle activity during the top half of the deadlift, while the middle trapezius displays superior muscle activity during the bottom half.

When comparing both vertical and horizontal pulling exercises, upper trapezius muscle activity is greater upright rowing movements, while middle trapezius muscle activity seems to be higher during horizontal rowing movements, such as the bent-over row.

During vertical pulling, trapezius muscle activity is not affected by grip width, stability at the hand or pulling angle. Both middle and upper trapezius muscle activity are maximised by using a pronated forearm position in the pull up.

During horizontal pulling, middle and upper trapezius display superior muscle activity during the bent over row, while middle trapezius muscle activity seems to be unaffected by stability at the hand or seated row technique.

During isolation exercises, the upper trapezius muscle is highly active during arm elevation and retraction exercises. The middle trapezius is highly active during retraction exercises, while the lower trapezius is highly active in shoulder abduction or flexion exercises with the arm at or above horizontal.


CONTENTS

Full table of contents

  1. Anatomy
  2. Muscle architecture
  3. Muscle fiber type
  4. Electromyography
  5. References
  6. Contributors
  7. Provide feedback


ANATOMY

PURPOSE

This purpose of this section is to provide a summary of the anatomy of the trapezius muscle.

ORIGINS AND INSERTIONS

Introduction

The origins and insertions describe where muscles are attached to the skeleton, via connective tissue. Basic conclusions can be drawn about the function of muscles from their origins and insertions, although muscle moment arms (see the next section) are more informative for this purpose. The origins and insertions of the trapezius span the superior and medial aspects of the back, connecting the shoulder joint and the scapula to the spine. The trapezius covers a large area of the upper back with a number of attachment sites including the cervical and thoracic spine, lateral third of the clavicle, acromion, and spine of the scapula.

Origins

The fascicles of the trapezius originate on the vertebrae or at the highest levels, including the intermuscular septum that spans from the back of the head (occipital protuberance) to the seventh cervical vertabrae. The trapezius muscle also originates from the spine between the cervical and the upper five spinous processes of the thoracic region (Johnson et al. 1996). As the trapezius is thought to comprise three regions that differ in muscle action, the upper, middle and lower fibers can be separated by their origin. The upper fibers originate from the back of the head (occiput) and inferiorly to the seventh cervical vertebrae. The middle fibers originate from the seventh cervical spinal process to the first thoracic spinal process. The lower fibers originate from the first to the seventh thoracic spinal processes (Johnson et al. 2005).

Insertions

The trapezius inserts on both the clavicle and scapula. The upper fibers that originate at the level of the cervical spine insert on the lateral third of the clavicle. The middle fibers insert near the distal end of the clavicle in proximity to the acromioclavicular joint. The lower fibers insert onto the spine of the scapula with the lowest fibers converging to the attachment site of the posterior deltoid (deltoid tubercle).

OVERALL WEIGHT AND SIZE

Introduction

The size and weight of muscles can be measured in various different ways. The most common ways to measure muscle size are by volume or by anatomical cross-sectional area. In addition, muscle weight and size can be presented either in absolute terms or relative to other muscles.

Muscle weight

Very limited data exists on the muscle weight of the trapezius. It appears that the trapezius muscle weight ranges between 34.7 – 313.6 g (Veeger et al. 1991). Comparing distinct attachments, Kamibayashi et al. (1998) measured the muscle weight of the fibers that insert on the clavicle or acromion. They reported that the muscle weight ranged between 10.7 to 27.1g in the fibers inserting to the clavicle, while the weight ranged between 68.5 – 128.4g in the acromion fibers.

Muscle cross-sectional area

Due to the shape of the trapezius muscle a more precise measure is to describe cross-sectional area of the muscle by region or by the origin of the fascicle. Elliot et al. (2007) investigated the regional cross-sectional area of the upper trapezius and found that the CSA increased with successively lower fibers between the third and seventh cervical vertabrae. The regional CSA ranged between approximately 100 – 1200mm2.

Muscle moment arms of the trapezius

Since the trapezius has main attachment sites at both the clavicle and scapula, its primary movements including elevation and depression, upward and downward rotation of the scapula, as well as abduction of the arm. To date, muscle moment arm studies using cadavers or computerised models have not been able to provide data on the moment arm lengths of the trapezius during its primary actions. However, Ackland et al. (2011) explored the moment arm lengths of the neck muscles and found that the upper and middle fibers of the trapezius displayed its greatest force producing capacity during neck extension. Further, the upper fibers appeared to contribute the greatest force potential during lateral bending of the three regions of the trapezius. In contrast, the lower trapezius did not display a large moment arm length and therefore does not contribute to extension, axial rotation or lateral bending of the neck.

SECTION CONCLUSIONS

The trapezius muscle originates on the spinous processes and ligamentous connective tissue that cover the upper cervical spine, between the C1 – T8, and insert on the lateral third of the clavicle, acromion and spine of the scapula.

Given its many mechanical lines of action, it is likely to be involved in many functions. However, it seems to function primarily as a shoulder girdle elevator, scapular upward (and downward) rotator, and shoulder abductor.


Top · Contents · References



MUSCLE ARCHITECTURE

[Read more about: muscle architecture]

PURPOSE

This purpose of this section is to provide a summary of the muscle architecture of the trapezius muscle.

MUSCLE THICKNESS

A number of studies have described the trapezius muscle thickness including differences between the three regions and areas closer to its origin or insertion. O’Sullivan et al. (2007) found that the lower trapezius muscle thickness was 3.1 ± 0.8 mm when measured with ultrasound. In contrast, O’Sullivan et al. (2009) measured the trapezius fascicles using magnetic resonance imaging (MRI) and found that the muscle thickness ranged between 3.8 – 15.4 mm depending on the muscle region and the part of the muscle being measured. When the thickest part of the muscle belly was measured, the muscle thickness was much greater in the middle fibers (15.4mm) compared with the lower fibers (6.8mm), respectively.

PENNATION ANGLE

Very limited data exists on the muscle pennation angle of the trapezius insofar that one study is available with sufficient measures. It appears that the pennation angle of the trapezius ranges between 0 – 30 degrees in the fibers inserting on the clavicle, and 0 – 10 degrees in the fibers inserting on the acromion (Kamibayashi et al. 1998).

FASCICLE LENGTH

As above, the data on muscle fascicle length in the trapezius in somewhat lacking. It appears that the fascicle length of the trapezius in the fibers inserting on the clavicle and acromion range between 62 – 104mm and 65 – 125mm, respectively (Kamibayashi et al. 1998).

PHYSIOLOGICAL CROSS-SECTIONAL AREA

A number of studies have investigated the physiological cross-sectional area (PCSA) of the trapezius It appears that the PCSA of the trapezius ranges between 0.6mm2 – 10.77mm2 depending on the region and measurement technique. Johnson et al. (1996) compared the fascicles of the trapezius with origins at the cervical (C3-6) and upper (T1) and lower (T5) thoracic vertabrae and reported that the PCSA was 2.3, 1.9 and 0.6mm2, respectively. Further, Kamibayashi et al. (1998) reported the PCSA for the fibers attaching to the clavicle or acromion, which were 1.96 and 10.77mm2 respectively, indicating that the fibers attaching to the acromion are capable of producing more force than the fibers connecting to the clavicle.

SECTION CONCLUSIONS

The trapezius muscle includes three regions that vary in architecture and size. The upper and middle fibers display greater PCSA and muscle thickness, respectively, compared with the lower fibers.

The fibers attaching to the acromion display the longest fascicle lengths. However, the upper fibers attaching to the clavicle are more heavily pennated than the fibers attaching to the acromion.


Top · Contents · References



MUSCLE FIBER TYPE

[Read more about: muscle fiber type]

PURPOSE

This section provides a summary of the muscle fiber type of the trapezius muscle.

MUSCLE FIBER TYPE

Muscle fiber type of the trapezius may be of interest to the strength and conditioning coaches in order to tailor their resistance-training program accordingly, especially if muscle hypertrophy is important. Kadi et al. (1998) reported that the trapezius muscle displays 64% type I muscle fibers, while type I muscle fiber distribution ranged between 62 – 79%. In contrast, Kadi et al. (1999) explored the muscle fiber type of the trapezius in competitive powerlifters and reported that muscle displays 55% type I muscle fibers. Eriksson et al. (2005) also explored the muscle fiber type of the trapezius in powerlifters and reported that the trapezius displays 46% type I muscle fibers in non-steroid users and 40% type I muscle fibers in steroid users. Regardless of steroid use, Eriksson reported that trapezius type I muscle fiber ranged between 28 – 62%. Therefore, the trapezius seems to display a mixed to slightly greater proportion of type I muscle fibers in non-strength athletes, while strength athletes may preferentially display a greater proportion of type II muscle fibers. As such, strength athletes may respond better to training with heavy loads and faster speeds, while non-strength athletes may respond better to a mix of heavy and lighter loads.

SECTION CONCLUSIONS

Studies to data suggest that strength athletes are likely to display a greater proportion of type II muscle fibers than type I muscle fibers, while non-strength athletes are more likely to display a mixed muscle fiber proportion. This may imply that training with higher speeds and heavier loads are more beneficial for strength athletes.  


Top · Contents · References



ELECTROMYOGRAPHY

[Read more about: electromyography]

PURPOSE

This section provides a summary of the electromyography (EMG) activity studies into the trapezius.

BACKGROUND

Introduction

Among sports scientists, it is widely accepted that electromyography (EMG) activity levels can provide a way for determining the best exercises for training a muscle. This is because EMG activity represents the extent to which the individual motor units within a muscle are active during a joint action. In non-fatigued muscles, the extent to which motor units are active determines the tensile force that is produced and this tensile force produces the mechanical loading that is thought to be one of the key drivers for long-term muscular adaptations (Schoenfeld, 2010).

MULTI-JOINT RESISTANCE TRAINING EXERCISES

Introduction

Several studies have directly compared the muscle activity of the trapezius muscle across a range of multi-joint resistance training exercises including the deadlift, horizontal and vertical upper-body pulling, as well as exercises utilising different load types, body posture and stability requirements. In general, it seems that compound exercises that involve carrying an external load with a flexed trunk (as in deadlift or bent-over row), shoulder adduction or shoulder extension (as in horizontal rows, pull-ups and lat pull-downs) all produce very high trapezius muscle activity. The upper trapezius appears to produce its greatest muscle activity during exercises that involve holding a heavy load in the hands while standing and/or include elevation of the scapula such as heavy deadlifts, bent-over rows and upright rows. The middle trapezius muscle appears to produce its greatest muscle activity during horizontal pulling exercises such as the bent-over row, seated row and inverted row regardless of stability requirement or scapula retraction. The lower trapezius appears to produce its greatest muscle activity during vertical pulling exercises such as the pull-up and lat pull-down regardless of grip width or pulling angle.

COMPARISON BETWEEN DIFFERENT TYPES OF COMPOUND EXERCISES

Upper trapezius

Comparing the effect of compound pulling exercises, Handa et al. (2005) investigated the upper trapezius mean muscle activity during a number of exercises including the upright row, seated cable row, bent-over row and lat pull-down to the front or rear. They reported that upper trapezius displayed its maximal muscle activity during the upright row (83 ± 19%) followed by the bent over row (78 ± 21%). They found greater muscle activity in the upright row compared with the seated row (83 ± 19 vs. 43 ± 32%) with 70% of 1RM. In contrast, they found no difference between the upright row and bent-over row, possibly because of the steeper trunk angle in the bent-over row than in the seated row.

Middle trapezius

Investigating the middle trapezius, Lehman et al. (2004) compared several upper-body pulling exercises, including the seated row and pull-down variations. When comparing the pull-down exercise performed with a supinated grip to the cable seated row, superior muscle activity was displayed during the seated row (21 ± 11 vs. 30 ± 12%). However, since the normalised muscle activity is considered low (<50%) with respect to resistance training exercises, it is unclear whether the difference would be apparent with greater relative loads. Handa et al. (2005) compared a number of upper body pulling exercises including the upright row, seated cable row, bent-over row and lat pull-down to the front or rear. Middle trapezius muscle activity was maximised during the bent-over row (89 ± 18%), followed by the upright row (67 ± 25%) and seated row (66 ± 29%). When comparing the bent-over row to the upright row, superior middle trapezius muscle activity was displayed during the bent-over row. In contrast, no difference in muscle activity was found between the bent-over row and seated row. Therefore, the middle trapezius appears to display its greatest muscle activity during horizontal rowing exercises.

Summary

It appears that upper trapezius muscle activity is greater upright rowing movements, while middle trapezius muscle activity seems to be higher during horizontal rowing movements, such as the bent-over row.

Back to top · Back to top of section · Down to references


THE DEADLIFT

[Read more: deadlift]

Effect of technique

Very little data exists comparing the effect of deadlift technique on trapezius muscle activity. It appears that trapezius muscle activity is greater with increasing load, and varies throughout the lifting phase regardless of deadlift type or grip technique.

Comparing conventional and sumo

Comparing the effect of deadlift type, Escamilla et al. (2002) compared the middle and upper trapezius muscle activity when performing different deadlift techniques, namely the conventional and sumo deadlift. They report no difference in either middle or upper trapezius muscle activity when comparing the sumo and conventional deadlift, with or without a belt.

Effect of barbell type

Comparing barbell type, Grostad (2013) explored the middle trapezius muscle activity during conventional deadlifts performed with a powerlifting or weightlifting bar with varying material stiffness. They report no difference in trapezius muscle activity between conditions.

Effect of relative load

When comparing the effect of load on trapezius muscle activity, Beggs et al. (2011) compared deadlifts with relative loads of 60% and 80% of 1RM. They reported superior muscle activity of the upper trapezius when performing deadlifts with 80% of 1RM compared with 60% of 1RM. Therefore, the data appears to indicate that the upper trapezius muscle activity is greater with increasing external load.

Effect of grip technique

Comparing the effect of grip technique, Beggs et al. (2011) investigated the use of either the double overhand or over-under grip technique on upper trapezius muscle activity and found no difference between conditions at either 60 or 80% of 1RM.

Effect of phase of lift

INTRODUCTION

Very little data exists comparing the effect of phase of lift on trapezius muscle activity. It appears that upper and middle trapezius muscle activity is affected by phase of lift whereby the upper trapezius displays superior activity during the later stages while the middle trapezius displays superior activity during the earlier. In practical terms, both upper and middle trapezius display high muscle activity at knee flexion angles of 31 – 60 degrees. Therefore, deadlift variations that amplify this range of motion may be beneficial.

UPPER TRAPEZIUS

Comparing the phase of lift, Carb et al. (2014) investigated the muscle activity of the upper trapezius during conventional deadlifts performed with a 1RM load, and further compared the muscle activity at the moment of lift-off and as the bar passed the knees. They reported that upper trapezius muscle activity ranged between 44 – 129% of MVC at lift-off and 81 – 129% at knee passage. It appears that upper trapezius muscle activity is greater at knee passage than at the moment of lift-off (97 vs. 88%) however it is unclear whether this was statistically significant. Escamilla et al. (2002) found that the peak upper trapezius muscle activity was displayed at a knee flexion angle between 60 – 31 degrees (mid lift), while the minimum muscle activity was displayed when the knee was between 61 – 90 degrees (lift off). Comparing the upper trapezius muscle activity during the three phases, greater muscle activity was displayed at the top of the deadlift (0 – 31 degrees) and middle portion (60 – 31 degrees) compared to the start of the lift (90 – 61 degrees), however no difference between the middle and top phases were found. Therefore, it appears that the upper trapezius muscle activity it maximised when the trunk is flexed slightly forward during minimal knee bend.

MIDDLE TRAPEZIUS

Investigating the middle trapezius, Escamilla et al. (2002) found that the peak middle trapezius muscle activity was greater when the knee flexion angle was between 90 – 61 degrees and 60 – 31 degrees compared with 0 – 31 degrees. Overall, it appears that the middle trapezius muscle activity is greater during the start and middle phases of the deadlift compared to the top of the lift. Therefore, it appears the middle trapezius muscle activity is maximised at the trunk angle achieved during the start and mid point of the deadlift.

Summary

It appears that trapezius muscle activity is greater with increasing load while deadlift type or grip technique has no effect. Upper trapezius muscle activity displays superior muscle activity during the top half of the deadlift, while the middle trapezius displays superior muscle activity during the bottom half.

Back to top · Back to top of section · Down to references


VERTICAL PULLING EXERCISES

Effect of lat pull-down technique

A number of studies have investigated the effect of variations in lat pull-down technique on trapezius muscle activity. It appears that middle and lower trapezius display similar muscle activity during the lat pull-down regardless of grip width, forearm orientation or pulling angle. Lower trapezius appears to display superior muscle activity during the first half of the range of motion.

Effect of grip width during lat pull-down

MIDDLE TRAPEZIUS

Investigating the effect of forearm orientation and grip width during the lat pull-down, Lusk et al. (2010) measured middle trapezius muscle activity. Four conditions were investigated including pronated and supinated grips performed with a wide grip (equal to the distance between the hands in the anatomical position) or narrow shoulder width grip. There was no difference (54 – 58% of MVIC) in middle trapezius muscle activity between narrow and wide conditions when performed at 70% of 1RM.

LOWER TRAPEZIUS

Comparing three grip widths during the lat pull-down exercise, Andersen et al. (2014) measured lower trapezius muscle activity with a 6RM load. They reported that lower trapezius muscle activity was similar (>100% MVC) in the lat pull-down exercise performed with a grip width equal to 1, 1.5 and 2 times shoulder (biacromial) width.

Effect of pulling angle during lat pull-down

Comparing performance of the lat pull-down to the front or rear, Pugh (2003) measured lower trapezius muscle activity. They found that lower trapezius muscle activity was no different between the front or rear conditions (36 ± 20 vs. 46 ± 24%), respectively. However, lower trapezius muscle activity was greater in the first phase (before the upper arms were horizontal) than the second phase in both conditions (41 ± 21 vs. 31 ± 22%).

Effect of forearm orientation during lat pull-down

Investigating the effect of forearm orientation and grip width during the lat pull-down, Lusk et al. (2010) measured middle trapezius muscle activity. Four conditions were investigated including pronated and supinated grips performed with a wide grip (equal to the distance between the hands in the anatomical position) or narrow shoulder width grip. They report no difference (54 – 58% MVC) in middle trapezius muscle activity between pronated and supinated conditions when performed with a load equal to 70% of 1RM. Lehman et al. (2004) compared the lat pull-down with a pronated or supinated grip. The researchers reported no difference in middle trapezius muscle activity (22.7 ± 11.5 vs. 20.5 ± 10.9%) between lat pull-downs regardless of forearm orientation.

Effect of pull up technique

Very little data exists comparing the effect of pull up variation on trapezius muscle activity. It appears that pull up variation and forearm orientation affect lower and middle trapezius muscle activity. Middle trapezius muscle activity seems to be superior during traditional pronated pull ups performed with or without a suspension device, while lower trapezius muscle activity appears to be superior during pronated compared with supinated pull ups.

Effect of pull up variation

Comparing the effect of pull-up variation, Snarr et al. (poster) investigated four variations of the pull-up including the traditional pronated pull up, suspension device pull-up performed with a pronated grip, towel pull-up performed with a semi neutral grip and the kipping pull-up that utilises momentum generated from the lower body. They report greater average middle trapezius muscle activity when performing the pull-up with a traditional or suspension (58 ± 14% vs. 56 ± 15%) technique compared with the towel or kipping condition.

Effect of forearm orientation during the pull-up exercise

Comparing the effect of forearm orientation, Youdas et al. (2010) explored the lower trapezius muscle activity during variations of the pull-up, including the pronated, supinated and rotating handle pull-up. They found that lower trapezius muscle activity was greater during the pronated pull-up compared with the supinated (56% vs. 45% of MVIC) condition. No other significant differences existed between the exercises regards to lower trapezius muscle activity. However, the pronated pull-up generally requires more effort than the supinated chin-up and therefore the difference in lower trapezius muscle activity may not exist when equal relative loads are utilised.

Effect of grip width during upright rows

UPPER TRAPEZIUS

Comparing the effect of grip, McAllister et al. (2013) explored the muscle activity during the upright row exercise performed with three different grip widths at 85% of 1RM. They report that upper trapezius muscle activity was no different during the concentric portion between grip widths equalling 50, 100 and 200% of shoulder width. However, upper trapezius muscle activity during the eccentric portion was superior during the 200% compared to all conditions, as well as superior muscle activity during the 100% condition compared with the 50% condition.

MIDDLE TRAPEZIUS

As above, McAllister et al. (2013) explored the muscle activity during the upright row with grip widths equalling 50, 100 or 200% of shoulder width performed with 85% of 1RM. They report a significantly greater middle trapezius muscle activity during the eccentric portion of the lift during the 200% condition compared with all others, while the muscle activity during the concentric portion tended to be greater when performing the exercise with greater grip width (100 vs. 50, and 200 vs. 100%).

Summary

During vertical pulling, middle and lower trapezius muscle activity does not appear to be affected by grip width, stability at the hand or pulling angle. However, the effect of forearm orientation during pull-ups is unclear, while it appears to have no affect during the lat pull-down.

Back to top · Back to top of section · Down to references


HORIZONTAL PULLING (ROWING) EXERCISES

Comparison of horizontal pulling (rowing) exercises

UPPER TRAPEZIUS

Handa et al. (2005) compared a number of upper body pulling exercises including the upright row, seated cable row, bent-over row and lat pull-down to the front or rear, to investigate the effect on peak muscle activity. They report superior upper trapezius muscle activity during the bent-over row compared with the cable seated row.

MIDDLE TRAPEZIUS

Comparing horizontal rowing-type exercises, Handa et al. explored the muscle activity of the middle trapezius during both the seated row and the bent-over row. They report no difference in muscle activity between the two conditions.

Effect of technique

Several studies have compared horizontal pulling exercises and variations in technique on trapezius muscle activity. It appears that the middle and upper trapezius display superior muscle activity during the bent over row, while middle trapezius muscle activity seems not to be affected by stability at the hand or seated row technique.

Effect of stability

Comparing the effect of stability during the inverted row exercise performed on a smith machine bar or using a suspension device, Snarr et al. (2013) reported that middle trapezius muscle activity was no different between conditions (99 ± 36 vs. 98 ± 54%).

Effect of scapula motions during seated row

Comparing the effect of scapula motion, Lehman et al. (2004) measured the middle trapezius muscle activity during the seated row with or without full scapula retraction. The researchers report that middle trapezius muscle activity tended to be greater during the seated row with retraction but was not statistically different compared to the seated row without retraction.

Effect of load type

Comparing the effect of load type, Bergquist (2015) investigated the muscle activity during a number of exercises performed with either isoinertial (dumbbells) or elastic loading. Comparing the face-pull exercise, the researchers found no difference in trapezius muscle activity during the concentric or eccentric phases.

Summary

It appears that the middle and upper trapezius display superior muscle activity during the bent over row, while middle trapezius muscle activity seems not to be affected by stability at the hand or seated row technique.

Back to top · Back to top of section · Down to references


COMPARISON OF ISOLATION EXERCISES

Effect of technique

INTRODUCTION

Very little data exists on the trapezius muscle activity during isolation exercises. It appears that relative load and shoulder abduction (coronal plane) affect upper trapezius muscle activity, while load-type appears to have no affect. The upper trapezius muscle is highly activity during arm elevation and retraction exercises. The middle trapezius is highly activity during retraction exercises, while the lower trapezius is highly activity in abduction/flexion exercises with the arm at or above horizontal, as well as horizontal rowing.

UPPER TRAPEZIUS

Comparing isolation exercises, Ekstrom et al. (2003) explored the muscle activity in the three regions of the trapezius during several shoulder exercises performed with a 5RM load. They found that the upper trapezius displays its maximum muscle activity during the shoulder shrug (119% MVC), followed by the prone reverse fly at 135 degrees of shoulder abduction with external rotation (79% of MVC), and the ‘full can’ exercise above 120 degrees flexion (79% of MVC). In contrast, Moseley et al. (1992) found that the upper trapezius displayed its maximum muscle activity during prone rowing (112% of MVC) when using loads equal to 10RM. There, it appears the upper trapezius muscle it highly active during elevation of the shoulder, and retraction to the scapula including rowing and horizontal abduction.

MIDDLE TRAPEZIUS

As above, Ekstrom et al. (2003) compared common shoulder rehabilitation exercises with a 5RM load. They report that the middle trapezius displayed its maximum muscle activity during the prone reverse fly at 135 degrees of shoulder abduction with external rotation (101% of MVC), followed by the prone reverse fly with external rotation (87% of MVC). In practical terms, it appears the middle trapezius muscle is highly active during exercises that involve scapula retraction. Moseley et al. (1992) also reported high muscle activity during the prone reverse fly with and without external rotation (96 vs. 108% of MVC).

LOWER TRAPEZIUS

As above, Ekstrom et al. (2003) compared common shoulder rehabilitation exercises with a 5RM on trapezius muscle activity. They report that the lower trapezius displayed its maximum muscle activity during the prone reverse fly at 135 degrees of shoulder abduction with external rotation (97% of MVC), followed by the prone reverse fly (79% of MVC). Moseley et al. (1992) explored several shoulder isolation exercises and found high muscle activity during the prone reverse fly also with and without external rotation (63 vs. 56% of MVC), but also reported high muscle activity during standing abduction above 120 degrees (68% of MVC) and prone rowing (67% of MVC). Therefore, the data indicates that the lower trapezius muscle displays high levels of muscle activity during horizontal abduction angles at or above 90 degrees coronal plane abduction, as well as scapular plane flexion (arms above head) and horizontal rowing.

Effect of relative load

When comparing the effect of load on trapezius muscle activity, Naddeo et al. (2008) compared the upper trapezius muscle activity during a seated isometric shrug exercise with relative loads between 10 – 80 % of MVC. They found that each successive increase of 10% relative load produced significantly greater upper trapezius muscle activity.

Effect of load type

Bergquist (2015) compared a number of exercises performed with either isoinertial load (dumbbells) or elastic resistance. Comparing the lying-prone reverse fly exercise, they found greater trapezius muscle activity when performing the exercise with elastic resistance compared to using dumbbells. Further, trapezius muscle activity was greater in both the 1st and 2nd half of the concentric and eccentric portions during the elastic condition.

Effect of shoulder joint angle

Comparing the effect of shoulder joint angle, Pizzari et al. (2014) measured muscle activity in all three regions of the trapezius muscle while performing a standard dumbbell shrug with the arms by the sides or abducted 30 degrees. They report that the upward rotation shrug (30 degrees abduction) displayed superior muscle activity in the upper, middle and lower regions. However, it must be made clear that the loads used were very small (2.5kg dumbbells) and whether the difference would translate to loads used in resistance training is unclear.

Summary

During isolation and rehabilitation exercises, the upper trapezius muscle is highly activity during arm elevation and retraction exercises. The middle trapezius is highly activity during retraction exercises, while the lower trapezius is highly activity in abduction/flexion exercises with the arm at or above horizontal, as well as horizontal rowing.

Back to top · Back to top of section · Down to references



REFERENCES

  1. Ackland, D. C., Merritt, J. S., & Pandy, M. G. (2011). Moment arms of the human neck muscles in flexion, bending and rotation. Journal of biomechanics, 44(3), 475-486. [PubMed]
  2. Beggs, L. A. (2011). Comparison Of Muscle Activation And Kinematics During The Deadlift Using A Double‐Pronated And Overhand/Underhand Grip. [Citation]
  3. Bischoff, E. (1863). Einige Gewichts-und Trockenbestimmungen der Organe des menschlichen Körpers. Ztschr. f. rat. Med, 20(75-118), 472. [Citation]
  4. Carbe, J., & Lind, A. (2014). A kinematic, kinetic and electromyographic analysis of 1-repetition maximum deadlifts. [Citation]
  5. Ekstrom, R. A., Donatelli, R. A., & Soderberg, G. L. (2003). Surface electromyographic analysis of exercises for the trapezius and serratus anterior muscles. Journal of Orthopaedic & Sports Physical Therapy, 33(5), 247-258. [PubMed]
  6. Escamilla, R. F., Francisco, A. C., Kayes, A. V., Speer, K. P., & Moorman 3rd, C. T. (2002). An electromyographic analysis of sumo and conventional style deadlifts. Medicine and science in sports and exercise, 34(4), 682-688. [PubMed]
  7. Elliott, J. M., Jull, G. A., Noteboom, J. T., Durbridge, G. L., & Gibbon, W. W. (2007). Magnetic resonance imaging study of cross‐sectional area of the cervical extensor musculature in an asymptomatic cohort. Clinical Anatomy, 20(1), 35-40. [PubMed]
  8. Eriksson, A., Kadi, F., Malm, C., & Thornell, L. E. (2005). Skeletal muscle morphology in power-lifters with and without anabolic steroids. Histochemistry and cell biology, 124(2), 167-175. [PubMed]
  9. Grostad, H. (2013). The effect of barbell-type on physical load in deadlift. [Citation]
  10. Handa, T., Kato, H., Hasegawa, S., Okada, J., & Kato, K. (2005). Comparative electromyographical investigation of the biceps brachii, latissimus dorsi, and trapezius muscles during five pull exercises. Japanese Journal of Physical Fitness and Sports Medicine, 54(2), 159-168. [Citation]
  11. Johnson, G. R., Spalding, D., Nowitzke, A., & Bogduk, N. (1996). Modelling the muscles of the scapula morphometric and coordinate data and functional implications. Journal of biomechanics, 29(8), 1039-1051. [PubMed]
  12. Johnson, G. R., & Pandyan, A. D. (2005). The activity in the three regions of the trapezius under controlled loading conditions—an experimental and modelling study. Clinical Biomechanics, 20(2), 155-161. [PubMed]
  13. Kadi, F., Waling, K., Ahlgren, C., Sundelin, G., Holmner, S., Butler-Browne, G. S., & Thornell, L. E. (1998). Pathological mechanisms implicated in localized female trapezius myalgia. Pain, 78(3), 191-196. [PubMed]
  14. Kadi, F., Hägg, G., Håkansson, R., Holmner, S., Butler-Browne, G. S., & Thornell, L. E. (1998). Structural changes in male trapezius muscle with work-related myalgia. Acta neuropathologica, 95(4), 352-360. [PubMed]
  15. Kadi, F., Eriksson, A., Holmner, S., Butler-Browne, G. S., & Thornell, L. E. (1999). Cellular adaptation of the trapezius muscle in strength-trained athletes. Histochemistry and cell biology, 111(3), 189-195. [PubMed]
  16. Kamibayashi, L. K., & Richmond, F. J. (1998). Morphometry of human neck muscles. Spine, 23(12), 1314-1323. [PubMed]
  17. Larsson, B., Björk, J., Elert, J., Lindman, R., & Gerdle, B. (2001). Fibre type proportion and fibre size in trapezius muscle biopsies from cleaners with and without myalgia and its correlation with ragged red fibres, cytochrome-c-oxidase-negative fibres, biomechanical output, perception of fatigue, and surface electromyography during repetitive forward flexions. European journal of applied physiology, 84(6), 492-502. [PubMed]
  18. Lehman, G. J., Buchan, D. D., Lundy, A., Myers, N., & Nalborczyk, A. (2004). Variations in muscle activation levels during traditional latissimus dorsi weight training exercises: An experimental study. Dynamic Medicine, 3(1), 4. [PubMed]
  19. Lindman, R., Hagberg, M., Ängqvist, K. A., Söderlund, K., Hultman, E., & Thornell, L. E. (1991). Changes in muscle morphology in chronic trapezius myalgia. Scandinavian journal of work, environment & health, 347-355. [PubMed]
  20. Lusk, S. J., Hale, B. D., & Russell, D. M. (2010). Grip width and forearm orientation effects on muscle activity during the lat pull-down. The Journal of Strength & Conditioning Research, 24(7), 1895-1900. [Pubmed]
  21. Moseley, J. B., Jobe, F. W., Pink, M., Perry, J., & Tibone, J. (1992). EMG analysis of the scapular muscles during a shoulder rehabilitation program. The American Journal of Sports Medicine, 20(2), 128-134. [PubMed]
  22. O’Sullivan, C., Meaney, J., Boyle, G., Gormley, J., & Stokes, M. (2009). The validity of rehabilitative ultrasound imaging for measurement of trapezius muscle thickness. Manual therapy, 14(5), 572-578. [PubMed]
  23. O’Sullivan, C., Bentman, S., Bennett, K., & Stokes, M. (2007). Rehabilitative ultrasound imaging of the lower trapezius muscle: technical description and reliability. journal of orthopaedic & sports physical therapy, 37(10), 620-626. [Citation]
  24. Pizzari, T., Wickham, J., Balster, S., Ganderton, C., & Watson, L. (2014). Modifying a shrug exercise can facilitate the upward rotator muscles of the scapula. Clinical Biomechanics, 29(2), 201-205. [PubMed]
  25. Pugh, G. M. G. (2003). A Biomechanical Comparison of the Front and Rear Lat Pull-down Exercise (Doctoral dissertation, University of Florida). [Citation]
  26. Seitz, A. L., Baxter, C. J., & Benya, K. (2015). Muscle thickness measurements of the lower trapezius with rehabilitative ultrasound imaging are confounded by scapular dyskinesis. Manual therapy. [PubMed]
  27. Shiino, K. (1913). Schultergelenkbewegungen und schulermuselarbeit. Arch Anat Physiol. (Suppl.) 1-88 [Citation]
  28. Snarr, R. L., Hallmark, A., Casey, J., Nickerson, B., & Esco, M. R. (2015). Electromyographic comparison of pull-up variations. Conference paper. [Citation]
  29. Thiele, F. W. (1884) Gewichtsbestimmungen zir entwickeung muskelsystems und skelettes menschen. Ksl Leop-Carol Deuchen Akad d Naturforscher, 46, 139-47 [Citation]
  30. Veeger, H. E. J., Van Der Helm, F. C. T., Van Der Woude, L. H. V., Pronk, G. M., & Rozendal, R. H. (1991). Inertia and muscle contraction parameters for musculoskeletal modelling of the shoulder mechanism. Journal of biomechanics, 24(7), 615-629. [Pubmed]
  31. Weber, E. F. (1851). Ueber die Langenverhaltnisse der Fleischfasern der Muskeln im allgemeinen. Berichte uber die Verhandlungen der Koniglich Sachsischen Akademie der Wissenschaften zu Leipsig, Mathematisch-physische Classe. Leipzig: Weidmannsche Buchhandlung. [Citation]
  32. Youdas, J. W., Amundson, C. L., Cicero, K. S., Hahn, J. J., Harezlak, D. T., & Hollman, J. H. (2010). Surface electromyographic activation patterns and elbow joint motion during a pull-up, chin-up, or perfect-pullup™ rotational exercise. The Journal of Strength & Conditioning Research, 24(12), 3404-3414. [Citation]


Top · Contents · References



CONTRIBUTORS

Adam Bentley performed the literature reviews, wrote the first draft of this page and was the primary author.

Chris Beardsley performed the first review of this page.


PROVIDE FEEDBACK

If you are knowledgable about this area of research, please help us improve this resource. Simply provide brief comments and your email address in the form below. Chris will then contact you by email to start the process of incorporating your feedback into the resource:

Your Name (required)

Your Email (required)

Your Message


Top · Contents · References