title: Effect of pelvic stabilization and hip position on trunk extensor activity during back extension exercises on a Roman chair.
abstract: OBJECTIVE
  To assess the effect of pelvic stabilization and hip position on the electromyographic activity of trunk extensors during Roman chair exercise. A secondary objective was to compare genders.
  
  
  METHODS
  Repeated measures.
  
  
  METHODS
  Eleven men and 11 women volunteers.
  
  
  METHODS
  Five trunk flexion-extension cycles for 3 Roman chair conditions: (i) pelvis unrestrained; (ii) pelvis restrained; and (iii) hip at 40 degrees flexion. Electromyographic signals were recorded on the back muscles, as well as on the gluteus maximus and biceps femoris. The percentage of electromyographic amplitude relative to the maximal activity was used to assess the level of muscular activation of each muscle group across the exercises.
  
  
  RESULTS
  For both genders, the Roman chair conditions did not influence the activity of the back and gluteus muscles. The hip-at-40 degrees-flexion condition significantly reduced the activity of the biceps femoris (average of 4-18%) relative to the other 2 conditions. Gender differences were observed on the activity of the biceps femoris in all Roman chair conditions.
  
  
  CONCLUSIONS
  The hip-at-40 degrees-flexion condition would allow the Roman chair exercise to train the targeted back muscles more specifically by overloading them over a longer duration in order to induce physiological changes.
authors.affiliation: Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal (CRIR), Montreal Rehabilitation Institute, Quebec, Canada.
authors.forename: Rubens A
authors.initials: RA
authors.lastname: da Silva
authors.forename: Christian
authors.initials: C
authors.lastname: Larivière
authors.forename: A Bertrand
authors.initials: AB
authors.lastname: Arsenault
authors.forename: Sylvie
authors.initials: S
authors.lastname: Nadeau
authors.forename: André
authors.initials: A
authors.lastname: Plamondon
mesh_terms: D000328:Adult; D001415:Back / Q000502:physiology*; D004576:Electromyography; D015444:Exercise / Q000502:physiology*; D005260:Female; D006615:Hip / Q000502:physiology*; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology*; D010388:Pelvis / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology; D016059:Range of Motion, Articular / Q000502:physiology; D012737:Sex Factors