title: Activation of selected shoulder muscles during unilateral wall and bench press tasks under submaximal isometric effort.
abstract: METHODS
  Controlled laboratory study.
  
  
  OBJECTIVE
  To assess the activation of 7 shoulder muscles under 2 closed kinetic chain (CKC) tasks for the upper extremity using submaximal isometric effort, thus providing relative quantification of muscular isometric effort for these muscles across the CKC exercises, which may be applied to rehabilitation protocols for individuals with shoulder weakness.
  
  
  BACKGROUND
  CKC exercises favor joint congruence, reduce shear load, and promote joint dynamic stability. Additionally, knowledge about glenohumeral and periscapular muscle activity elicited during CKC exercises may help clinicians to design protocols for shoulder rehabilitation.
  
  
  METHODS
  Using surface electromyography, activation level was measured across 7 shoulder muscles in 20 healthy males, during the performance of a submaximal isometric wall press and bench press. Signals were normalized to the maximal voluntary isometric contraction, and, using paired t tests, data were analyzed between the exercises for each muscle.
  
  
  RESULTS
  Compared to the wall press, the bench press elicited higher activity for most muscles, except for the upper trapezius. Levels of activity were usually low but were above 20% maximal voluntary isometric contraction for the serratus anterior on both tasks, and for the long head triceps brachii on the bench press.
  
  
  CONCLUSIONS
  Both the bench press and wall press, as performed in this study, led to relatively low EMG activation levels for the muscles measured and may be considered for use in the early phases of rehabilitation.
authors.affiliation: Department of Biomechanics, Medicine and Rehabilitation of Locomotor Apparatus, School of Medicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil. helgatucci@yahoo.com.br
authors.forename: Helga T
authors.initials: HT
authors.lastname: Tucci
authors.forename: Marcia A
authors.initials: MA
authors.lastname: Ciol
authors.forename: Rodrigo C
authors.initials: RC
authors.lastname: de Araújo
authors.forename: Rodrigo
authors.initials: R
authors.lastname: de Andrade
authors.forename: Jaqueline
authors.initials: J
authors.lastname: Martins
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: McQuade
authors.forename: Anamaria S
authors.initials: AS
authors.lastname: Oliveira
mesh_terms: D000293:Adolescent; D000328:Adult; D004576:Electromyography; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology; D055070:Resistance Training / Q000379:methods*; D012782:Shoulder / Q000502:physiology*; D055815:Young Adult