Relative Balance of Serratus Anterior and Upper Trapezius Muscle Activity during Push-Up Exercises

Background Serratus anterior strengthening is used in prevention and treatment programs for poor scapular control. In certain clinical cases, exercises substantially activating the serratus with minimal upper trapezius activation are preferred. Hypothesis The standard push-up plus would show both the highest serratus anterior activation and lowest upper trapezius/ serratus ratios for both groups and all phases. Study Design Controlled laboratory study. Methods Thirty subjects, grouped as healthy or with mild shoulder dysfunction, were evaluated performing standard push-up plus exercises and modifications on elbows, knees, and against a wall. Surface electromyography of the serratus anterior and upper trapezius was compared between exercises. Results Both groups responded similarly across exercises. The standard push-up plus demonstrated the highest activation of the serratus (to 123%) and lowest trapezius/serratus ratios (< 0.2) during plus phases. The wall push-up plus and phases of other exercises demonstrated higher upper trapezius/serratus ratios (to 2.0). Conclusions In clinical cases where excess upper trapezius activation or imbalance of serratus and trapezius activation occurs, the push-up plus is an optimal exercise. Other cases may benefit from a progression of modified push-up exercises. Clinical Relevance Clinical selection of exercises for improving scapular control should consider both maximum serratus activation and upper trapezius/serratus anterior ratios.

[1]  B F Morrey,et al.  Three‐dimensional kinematics of glenohumeral elevation , 1991, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[2]  B Sennett,et al.  Comparison of 3-dimensional scapular position and orientation between subjects with and without shoulder impingement. , 1999, The Journal of orthopaedic and sports physical therapy.

[3]  Childress Ds,et al.  Relationships of the surface electromyogram to the force, length, velocity, and contraction rate of the cineplastic human biceps. , 1981 .

[4]  B. Morrey,et al.  Surgery of the Shoulder , 1990 .

[5]  M P Kadaba,et al.  A kinematic and electromyographic study of shoulder rehabilitation exercises. , 1993, Clinical orthopaedics and related research.

[6]  C. Davies,et al.  Adaptive response of mammalian skeletal muscle to exercise with high loads , 1984, European Journal of Applied Physiology and Occupational Physiology.

[7]  S. Sahrmann Diagnosis and Treatment of Movement Impairment Syndromes , 2001 .

[8]  K Schüldt,et al.  Activity levels during isometric test contractions of neck and shoulder muscles. , 1988, Scandinavian journal of rehabilitation medicine.

[9]  M L Pearl,et al.  Dynamic electromyographic analysis of the throwing shoulder with glenohumeral instability. , 1988, The Journal of bone and joint surgery. American volume.

[10]  T. Cook,et al.  Alterations in shoulder kinematics and associated muscle activity in people with symptoms of shoulder impingement. , 2000, Physical therapy.

[11]  A. Browne,et al.  The painful shoulder during freestyle swimming. An electromyographic cinematographic analysis of twelve muscles. , 1991, The American journal of sports medicine.

[12]  R E Grahame,et al.  Electromyographic analysis of soft tissue lesions affecting shoulder function. , 1977, American journal of physical medicine.

[13]  K N An,et al.  Kinematic and kinetic analysis of push-up exercise. , 1990, Biomedical sciences instrumentation.

[14]  Thomas M Cook,et al.  Translations of the humerus in persons with shoulder impingement symptoms. , 2002, The Journal of orthopaedic and sports physical therapy.

[15]  M. T. Gross,et al.  An electromyographical analysis of the scapular stabilizing synergists during a push-up progression. , 1998, The Journal of orthopaedic and sports physical therapy.

[16]  N. Berme,et al.  The shoulder complex in elevation of the arm: a mechanism approach. , 1978, Journal of biomechanics.

[17]  D A Nawoczenski,et al.  Three-dimensional scapular orientation and muscle activity at selected positions of humeral elevation. , 1996, The Journal of orthopaedic and sports physical therapy.

[18]  L. Portney,et al.  Foundations of Clinical Research , 1993 .

[19]  Frank W. Jobe,et al.  EMG analysis of the scapular muscles during a shoulder rehabilitation program , 1992, The American journal of sports medicine.

[20]  Carl G Mattacola,et al.  Shoulder musculature activation during upper extremity weight-bearing exercise. , 2003, The Journal of orthopaedic and sports physical therapy.

[21]  J. Saunders,et al.  Observations of the Function of the Shoulder Joint , 1996, Clinical orthopaedics and related research.

[22]  G. W. Lange,et al.  Electromyographic Activity and Applied Load During Shoulder Rehabilitation Exercises Using Elastic Resistance , 1998, The American journal of sports medicine.

[23]  J. Perry,et al.  The normal shoulder during freestyle swimming. An electromyographic and cinematographic analysis of twelve muscles. , 1991, The American journal of sports medicine.

[24]  Thomas M. Cook,et al.  Comparison of Surface Sensor and Bone-Fixed Measurement of Humeral Motion , 2002 .

[25]  D. Childress,et al.  Relationships of the surface electromyogram to the force, length, velocity, and contraction rate of the cineplastic human biceps. , 1981, American journal of physical medicine.

[26]  K. L. Moore,et al.  Clinically Oriented Anatomy , 1985 .

[27]  Kenneth J. Faber,et al.  Serratus Anterior Muscle Activity During Selected Rehabilitation Exercises , 1999, The American journal of sports medicine.

[28]  C. Jensen,et al.  The influence of electrode position on bipolar surface electromyogram recordings of the upper trapezius muscle , 2004, European Journal of Applied Physiology and Occupational Physiology.