title: Trunk muscle activity during spine stabilization exercises performed in a pool.
abstract: OBJECTIVE
  To compare trunk muscle activity levels among a variety of therapeutic aquatic exercises designed for patients with low back pain.
  
  
  METHODS
  Quantitative observational laboratory study.
  
  
  METHODS
  Sports medicine clinic housed in a University.
  
  
  METHODS
  Eleven physically active males aged 25.7 ± 5.53 years.
  
  
  METHODS
  Surface electromyographic (EMG) data from muscles rectus abdominis (RA), external oblique (EO), lower abdominals (LA), multifidus (MT), and erector spinae (ES) were recorded and then normalized to a maximal voluntary contraction.
  
  
  RESULTS
  EMG values during abdominal bracing and Swiss ball exercises for muscles RA, EO, LA, and ES were significantly greater than most other exercises tested that included pelvic tilt, marching, hip abduction, and alternating arm exercises (P = .04-.001). EMG values of muscle LA were also greater for the abdominal hollowing exercise, whereas muscle MT displayed the greatest EMG values during the hip abduction exercise when compared to most other exercises tested (P = .02-.001).
  
  
  CONCLUSIONS
  The aquatic exercises that maximize trunk muscle activity in the healthy males studied are abdominal bracing and Swiss ball exercises. Some muscles were selectively activated during abdominal hollowing (LA) and hip abduction (MT) exercises when compared to most other exercises.
authors.affiliation: Biomechanics Laboratory, HPER Department, Utah State University, 7000 Old Main Hill, Logan, UT 84322, USA. eadric.bressel@usu.edu
authors.forename: Eadric
authors.initials: E
authors.lastname: Bressel
authors.forename: Dennis G
authors.initials: DG
authors.lastname: Dolny
authors.forename: Coby
authors.initials: C
authors.lastname: Vandenberg
authors.forename: John B
authors.initials: JB
authors.lastname: Cronin
mesh_terms: D000328:Adult; D004576:Electromyography; D005081:Exercise Therapy; D006801:Humans; D017116:Low Back Pain / Q000534:rehabilitation*; D008297:Male; D013131:Spine / Q000502:physiology*; D013551:Swimming Pools; D055815:Young Adult