title: Effect of Humeral-Elevation Angle on Electromyographic Activity in the Serratus Anterior During the Push-Up-Plus Exercise.
abstract: BACKGROUND
  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.
  
  
  OBJECTIVE
  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.
  
  
  METHODS
  Comparative, repeated-measures design.
  
  
  METHODS
  University research laboratory.
  
  
  METHODS
  29 healthy men.
  
  
  METHODS
  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°.
  
  
  CONCLUSIONS
  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°.
authors.forename: Ui-Jae
authors.initials: UJ
authors.lastname: Hwang
authors.forename: Oh-Yun
authors.initials: OY
authors.lastname: Kwon
authors.forename: In-Cheol
authors.initials: IC
authors.lastname: Jeon
authors.forename: Si-Hyun
authors.initials: SH
authors.lastname: Kim
authors.forename: Jong-Hyuck
authors.initials: JH
authors.lastname: Weon
mesh_terms: D000328:Adult; D004576:Electromyography; D005080:Exercise Test / Q000379:methods*; D006801:Humans; D006811:Humerus / Q000502:physiology*; D007537:Isometric Contraction / Q000502:physiology; D008297:Male; D016059:Range of Motion, Articular / Q000502:physiology*; D055815:Young Adult
keywords: activity ratio; maximum contraction; selective activation