Incorporation of the Kinetic Chain Into Shoulder-Elevation Exercises: Does It Affect Scapular Muscle Activity?

Context Scapular rehabilitation exercises should focus on selective activation of weaker muscles and minimal activation of hyperactive muscles. For rehabilitation of overhead athletes, single-plane open chain exercises below 90° of shoulder elevation are often recommended. Moreover, incorporating the kinetic chain in shoulder rehabilitation exercises is advised and has been suggested to influence scapular muscle activity levels. Objective To study the influence of kinetic chain incorporation during 5 variations of a shoulder-elevation exercise on scapular muscle activity. Design Cross-sectional study. Setting University laboratory. Patients or Other Participants Thirty-one asymptomatic participants (15 men, 16 women). Main Outcome Measure(s) The electromyographic activity of the upper (UT), middle (MT), and lower (LT) trapezius, and serratus anterior was determined during 5 variations of bilateral elevation with external rotation: (1) open-hand position (reference exercise), (2) closed-hand position, (3) dynamic bipedal squat, (4) static unipedal squat, and (5) dynamic unipedal squat on the contralateral leg. All data were normalized as a percentage of maximal voluntary isometric contraction (MVIC). Results A closed-hand position (exercise 2) instead of an open-hand position (exercise 1) resulted in lower MT (mean difference = 3.44% MVIC) and LT (mean difference = 7.76% MVIC) activity. Incorporating the lower limb (exercises 3–5) increased UT activity when compared with exercise 1 (mean differences = 3.67, 2.68, 5.02% MVIC, respectively), which in general resulted in increased UT : MT ratios. Additionally, LT activity decreased when a dynamic unipedal squat was added (mean difference: 4.90% MVIC). For the serratus anterior, the greatest activity occurred during elevation in a static unipedal squat position (exercise 4, 22.90% MVIC). Conclusions Incorporating the kinetic chain during shoulder-elevation exercises influenced scapular muscle activity and ratios. In particular, incorporating the lower limb resulted in more UT activity, whereas the open-hand position increased MT and LT activity.

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Electromyographic Activity and Applied Load During Shoulder Rehabilitation Exercises Using Elastic Resistance

The American Journal of Sports Medicine ◽

10.1177/03635465980260021001 ◽

1998 ◽

Vol 26 (2) ◽

pp. 210-220 ◽

Cited By ~ 175

Author(s):

Robert A. Hintermeister ◽

Gregory W. Lange ◽

Jeanne M. Schultheis ◽

Michael J. Bey ◽

Richard J. Hawkins

Keyword(s):

Muscle Activity ◽

Applied Load ◽

Activity Patterns ◽

Electromyographic Activity ◽

Serratus Anterior ◽

Elastic Resistance ◽

Intramuscular Electrodes ◽

Anterior Deltoid ◽

Voluntary Contractions ◽

Rehabilitation Exercises

Muscle activity (measured by electromyography) and applied load were measured during seven shoulder rehabilitation exercises done with an elastic resistance device. Nineteen men with no shoulder abnormalities performed seven exercises: external and internal rotation, forward punch, shoulder shrug, and seated rowing with a narrow, middle, and wide grip. Qualitative video (60 Hz) was synchronized with the electromyography data from eight muscles (2000 Hz). Fine-wire intramuscular electrodes were inserted into the supraspinatus and subscapularis muscles, and surface electrodes were placed over the anterior deltoid, infraspinatus, pectoralis major, latissimus dorsi, serratus anterior, and trapezius muscles. Ten trials per subject were analyzed for average and peak amplitude, and the results were expressed as a percentage of maximum voluntary contractions. The peak loads for all exercises ranged from 21 to 54 N. The muscle activity patterns suggest that these shoulder rehabilitation exercises incorporating elastic resistance, controlled movements, and low initial loading effectively target the rotator cuff and supporting musculature and are appropriate for postinjury and postoperative patients.

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The Activity of Surface Electromyographic Signal of Selected Muscles during Classic Rehabilitation Exercise

Rehabilitation Research and Practice ◽

10.1155/2016/4796875 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Jinzhuang Xiao ◽

Jinli Sun ◽

Junmin Gao ◽

Hongrui Wang ◽

Xincai Yang

Keyword(s):

Lower Limb ◽

Muscle Activity ◽

Activity Level ◽

Core Stability ◽

Median Frequency ◽

Low Back ◽

Lower Limb Muscles ◽

Significant Difference ◽

Limb Muscles ◽

Rehabilitation Exercises

Objectives. Prone bridge, unilateral bridge, supine bridge, and bird-dog are classic rehabilitation exercises, which have been advocated as effective ways to improve core stability among healthy individuals and patients with low back pain. The aim of this study was to investigate the activity of seven selected muscles during rehabilitation exercises through the signal of surface electromyographic. Approaches. We measured the surface electromyographic signals of four lower limb muscles, two abdominal muscles, and one back muscle during rehabilitation exercises of 30 healthy students and then analyzed its activity level using the median frequency method. Results. Different levels of muscle activity during the four rehabilitation exercises were observed. The prone bridge and unilateral bridge caused the greatest muscle fatigue; however, the supine bridge generated the lowest muscle activity. There was no significant difference (P>0.05) between left and right body side muscles in the median frequency slope during the four rehabilitation exercises of seven muscles. Conclusions. The prone bridge can affect the low back and lower limb muscles of most people. The unilateral bridge was found to stimulate muscles much more active than the supine bridge. The bird-dog does not cause much fatigue to muscles but can make most selected muscles active.

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Role of the kinetic chain in shoulder rehabilitation: does incorporating the trunk and lower limb into shoulder exercise regimes influence shoulder muscle recruitment patterns? Systematic review of electromyography studies

BMJ Open Sport & Exercise Medicine ◽

10.1136/bmjsem-2019-000683 ◽

2020 ◽

Vol 6 (1) ◽

pp. e000683

Author(s):

Eleanor Richardson ◽

Jeremy S Lewis ◽

Jo Gibson ◽

Chris Morgan ◽

Mark Halaki ◽

...

Keyword(s):

Systematic Review ◽

Lower Limb ◽

Trapezius Muscle ◽

Cochrane Central Register ◽

Muscle Recruitment ◽

Kinetic Chain ◽

Serratus Anterior ◽

Significant Difference ◽

Recruitment Patterns ◽

Lower Trapezius

ObjectiveTo investigate the influence of trunk and lower limb motion on electromyography (EMG) muscle activity and recruitment patterns around the shoulder.DesignSystematic review.Data sourcesMEDLINE, CINAHL, PEDro, AMED, PubMed, Cochrane Central Register of Controlled trials, Cochrane Database of Systematic reviews, SportsDiscuss and PROSPERO.Eligibility criteriaStudies investigating both multiregional kinetic chain (KC) shoulder exercises and localised non-kinetic chain (nKC) shoulder exercises in healthy subjects under the same experimental conditions were included in this review.ResultsKC exercises produced greater EMG activation levels in 5 of 11 studies for the lower trapezius. Of the remaining studies, five found no difference between the exercise types and one favoured nKC exercises. KC exercises produced greater EMG activation levels in 5 of 11 studies for the serratus anterior. Of the remaining studies, three reported the opposite and three found no significant difference between the exercise types. nKC exercises produced greater EMG activation in infraspinatus in three of four studies. KC exercises produced the lowest trapezius muscle ratios in all studies. Studies investigating the upper trapezius, middle trapezius, supraspinatus, subscapularis, biceps brachii, latifissimus dorsi, pectoralis major, deltoid, and trapezius and serratus anterior ratios showed inconsistency.ConclusionThis review found evidence that integrating the KC during shoulder rehabilitation may increase axioscapular muscle recruitment, produce lower trapezius muscle ratios and reduce the demands on the rotator cuff. Stepping appears preferable to squatting.PROSPERO registration numberCRD42015032557, 2015.

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Alterations in Shoulder Kinematics and Associated Muscle Activity in People With Symptoms of Shoulder Impingement

Physical Therapy ◽

10.1093/ptj/80.3.276 ◽

2000 ◽

Vol 80 (3) ◽

pp. 276-291 ◽

Cited By ~ 900

Author(s):

Paula M Ludewig ◽

Thomas M Cook

Keyword(s):

Occupational Exposure ◽

Muscle Activity ◽

Load Condition ◽

Trapezius Muscle ◽

Electromyographic Activity ◽

Serratus Anterior Muscle ◽

Serratus Anterior ◽

Shoulder Impingement ◽

Upper Trapezius ◽

Load Conditions

AbstractBackground and Purpose. Treatment of patients with impingement symptoms commonly includes exercises intended to restore “normal” movement patterns. Evidence that indicates the existence of abnormal patterns in people with shoulder pain is limited. The purpose of this investigation was to analyze glenohumeral and scapulothoracic kinematics and associated scapulothoracic muscle activity in a group of subjects with symptoms of shoulder impingement relative to a group of subjects without symptoms of shoulder impingement matched for occupational exposure to overhead work. Subjects. Fifty-two subjects were recruited from a population of construction workers with routine exposure to overhead work. Methods. Surface electromyographic data were collected from the upper and lower parts of the trapezius muscle and from the serratus anterior muscle. Electromagnetic sensors simultaneously tracked 3-dimensional motion of the trunk, scapula, and humerus during humeral elevation in the scapular plane in 3 hand-held load conditions: (1) no load, (2) 2.3-kg load, and (3) 4.6-kg load. An analysis of variance model was used to test for group and load effects for 3 phases of motion (31°–60°, 61°–90°, and 91°–120°). Results. Relative to the group without impingement, the group with impingement showed decreased scapular upward rotation at the end of the first of the 3 phases of interest, increased anterior tipping at the end of the third phase of interest, and increased scapular medial rotation under the load conditions. At the same time, upper and lower trapezius muscle electromyographic activity increased in the group with impingement as compared with the group without impingement in the final 2 phases, although the upper trapezius muscle changes were apparent only during the 4.6-kg load condition. The serratus anterior muscle demonstrated decreased activity in the group with impingement across all loads and phases. Conclusion and Discussion. Scapular tipping (rotation about a medial to lateral axis) and serratus anterior muscle function are important to consider in the rehabilitation of patients with symptoms of shoulder impingement related to occupational exposure to overhead work.

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Effect of Humeral-Elevation Angle on Electromyographic Activity in the Serratus Anterior During the Push-Up-Plus Exercise

Journal of Sport Rehabilitation ◽

10.1123/jsr.2015-0090 ◽

2017 ◽

Vol 26 (1) ◽

pp. 57-64 ◽

Cited By ~ 6

Author(s):

Ui-jae Hwang ◽

Oh-yun Kwon ◽

In-cheol Jeon ◽

Si-hyun Kim ◽

Jong-hyuck Weon

Keyword(s):

Outcome Measures ◽

Muscle Activity ◽

Repeated Measures ◽

Elevation Angle ◽

Emg Activity ◽

Electromyographic Activity ◽

Serratus Anterior ◽

Repeated Measures Design ◽

Activity Ratios ◽

Push Up

Context:The push-up-plus (PP) exercise has been recommended for strengthening of the serratus anterior (SA). Previous studies have investigated the effect of different stability properties of the base of support to adjust the difficulty level of SA muscle-strengthening exercises in the PP position. However, the optimal humeral-elevation angle (HEA) for selective activation and maximum contraction of the SA during PP has not been investigated.Objectives:To assess the effects of HEA during PP on electromyographic (EMG) activity in the SA, upper trapezius (UT), and pectoralis major (PM) and on the UT:SA and PM:SA activity ratios.Design:Comparative, repeated-measures design.Setting:University research laboratory.Participants:29 healthy men.Main Outcome Measures:The subjects performed PP at 3 different HEAs (60°, 90°, and 120°); EMG activity in the SA, UT, and PM was measured, and the UT:SA and PM:SA activity ratios were calculated. Differences in muscle activity and ratios between the 60°, 90°, and 120° HEAs were assessed using 1-way repeated-measures analysis of variance; the Bonferroni correction was applied.Results:SA muscle activity was significantly increased, in order of magnitude, at the 120°, 90°, and 60° HEAs. UT:SA and PM:SA activity ratios were significantly greater during performance of the PP at an HEA of 60° than at HEAs of 120° and 90°.Conclusion:The results suggest that an HEA of 120° should be used during performance of the PP because it produces greater SA activation than HEAs of 60° and 90°.

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A Comparison of the Serratus Anterior Muscle Activity according to the Shoulder Flexion Angles in a Closed Kinetic Chain Exercise and an Open Kinetic Chain Exercise

Journal of the Korean Society of Physical Medicine ◽

10.13066/kspm.2013.8.3.369 ◽

2013 ◽

Vol 8 (3) ◽

pp. 369-378 ◽

Cited By ~ 3

Author(s):

Sung-Jong Moon ◽

Tack-Hoon Kim ◽

Jung-Suk Roh

Keyword(s):

Muscle Activity ◽

Serratus Anterior Muscle ◽

Kinetic Chain ◽

Serratus Anterior ◽

Shoulder Flexion ◽

Open Kinetic Chain ◽

Closed Kinetic Chain

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Serratus Anterior Muscle Activity During Selected Rehabilitation Exercises

The American Journal of Sports Medicine ◽

10.1177/03635465990270061601 ◽

1999 ◽

Vol 27 (6) ◽

pp. 784-791 ◽

Cited By ~ 233

Author(s):

Michael J. Decker ◽

Robert A. Hintermeister ◽

Kenneth J. Faber ◽

Richard J. Hawkins

Keyword(s):

Muscle Activity ◽

Serratus Anterior Muscle ◽

Serratus Anterior ◽

Rehabilitation Exercises

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A Systematic Review of Rehabilitation Exercises to Progressively Load the Gluteus Medius

Journal of Sport Rehabilitation ◽

10.1123/jsr.2016-0088 ◽

2017 ◽

Vol 26 (5) ◽

pp. 418-436 ◽

Cited By ~ 10

Author(s):

Jay R. Ebert ◽

Peter K. Edwards ◽

Daniel P. Fick ◽

Gregory C. Janes

Keyword(s):

Lower Limb ◽

Evidence Synthesis ◽

Weight Bearing ◽

Gluteus Medius ◽

High Load ◽

Electromyographic Activity ◽

Hip Abduction ◽

Exercise Type ◽

Rehabilitation Exercises ◽

Very High

Context:Gluteus medius rehabilitation is of critical importance given its role in pelvic and lower limb stability, and the known link between gluteus medius weakness and many lower limb conditions.Objective:To systematically review the literature and present an evidence-based graduated series of exercises to progressively load gluteus medius.Evidence Acquisition:A systematic literature search was conducted in January 2016 to identify studies reporting gluteus medius muscle activity as a percentage of maximal volitional isometric contraction (MVIC), during rehabilitation exercises. Studies that investigated injury free participants were included. No restrictions were placed on the type or mode of exercise, though exercises that could not be accurately replicated or performed within an independent setting were excluded. Studies that did not normalize electromyographic activity to a side lying MVIC were excluded. Exercises were stratified based on exercise type and %MVIC: low (0% to 20%), moderate (21% to 40%), high (41% to 60%), and very high (> 61%).Evidence Synthesis:20 studies were included in this review, reporting outcomes in 33 exercises (and a range of variations of the same exercise). Prone, quadruped, and bilateral bridge exercises generally produced low or moderate load. Specific hip abduction/rotation exercises were reported as moderate, high, or very high load. Unilateral stance exercises in the presence of contralateral limb movement were often high or very high load activities, while high variability existed across a range of functional weight-bearing exercises.Conclusions:This review outlined a series of exercises commonly employed in a rehabilitation setting, stratified based on exercise type and the magnitude of gluteus medius muscular activation. This will assist clinicians in tailoring gluteus medius loading regimens to patients, from the early postoperative through to later stages of rehabilitation.

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Analysis of Scapular Kinematics and Muscle Activity by Use of Fine-Wire Electrodes During Shoulder Exercises

The American Journal of Sports Medicine ◽

10.1177/0363546520908604 ◽

2020 ◽

Vol 48 (5) ◽

pp. 1213-1219

Author(s):

Kelly Berckmans ◽

Birgit Castelein ◽

Dorien Borms ◽

Tanneke Palmans ◽

Thierry Parlevliet ◽

...

Keyword(s):

Muscle Activity ◽

Mixed Model ◽

Linear Mixed Model ◽

Moderate Activity ◽

Limited Information ◽

Serratus Anterior ◽

Postoperative Rehabilitation ◽

Scapular Kinematics ◽

Fine Wire ◽

Rehabilitation Exercises

Background: During nonoperative or postoperative rehabilitation after sports injuries, exercise selection is often based on minimal load on the injured/repaired glenohumeral structures, while optimally activating scapulothoracic muscles. Previous research explored scapular muscle activity during rehabilitation exercises using surface electromyography (EMG). However, limited information exists about the deeper lying muscle activity, measured with fine-wire electrodes, even more in combination with 3-dimensional scapular kinematics. Purpose: To report scapular kinematics synchronously with surface and fine-wire EMG during specific shoulder exercises for early rehabilitation. Study Design: Descriptive laboratory study. Methods: A total of 23 healthy male patients were recruited. Three-dimensional scapular kinematics were measured combined with EMG recording of 8 muscles during 4 commonly used shoulder exercises (inferior glide, low row, lawnmower, and robbery). Upper (UT), middle (MT), and lower (LT) trapezius and serratus anterior muscle activities were measured with bipolar surface electrodes. Intramuscular electrodes were placed in the levator scapulae (LS), rhomboid major (RM), pectoralis minor (Pm), and infraspinatus (IS) muscles. All data were normalized as a percentage of maximal voluntary isometric contraction (%MVIC). A linear mixed model with Bonferroni correction was applied for statistical analysis. Results: Scapular kinematics revealed an anterior tilt position during the inferior glide, low row, and robbery ( P < .05). An upward rotation position between 20° and 30° was reached in all exercises except low row. Inferior glide (31°) and low row (42°) represented a significantly increased internal rotation position compared with lawnmower and robbery. Lawnmower and robbery showed significantly ( P < .05) more MT (lawnmower, 36% MVIC; robbery, 39% MVIC) and RM (lawnmower, 59% MVIC; robbery, 66% MVIC) activation compared with inferior glide and low row. Lawnmower and robbery showed significantly ( P < .05) less Pm activation (9.5%-12% MVIC). LS was significantly more active during robbery (58% MVIC) compared with inferior glide and low row (27%-36% MVIC) ( P < .05). IS showed moderate activity (24%-37% MVIC) for all exercises, except low row (13% MVIC). Conclusion/Clinical Relevance: This study provides new insights about scapular positions and activation of the deeper layer muscles during 4 commonly used shoulder rehabilitation exercises. The lawnmower showed a favorable position of the scapula with less Pm activity in contrast to the low row. The inferior glide, lawnmower, and robbery should not be implemented in early phases of shoulder rehabilitation because of their moderate muscle activity.

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