title: Specific trunk and general exercise elicit similar changes in anticipatory postural adjustments in patients with chronic low back pain: a randomized controlled trial.
abstract: METHODS
  A randomized controlled trial.
  
  
  OBJECTIVE
  To compare changes in self-rated disability, pain, and anticipatory postural adjustments between specific trunk exercise and general exercise in patients with chronic low back pain.
  
  
  BACKGROUND
  Chronic low back pain is associated with altered motor control of the trunk muscles. The best exercise to address altered motor control is unclear.
  
  
  METHODS
  Sixty-four patients with chronic low back pain were randomly assigned to a specific trunk exercise group (SEG) that included skilled cognitive activation of the trunk muscles in addition to a number of other best practice exercises, whereas the general exercise group performed only seated cycling exercise. The training program lasted for 8 weeks. Self-rated disability and pain scores were collected before and after the training period. Electromyographic activity of various trunk muscles was recorded during performance of a rapid shoulder flexion task before and after training. Muscle onsets were calculated, and the latency time (in ms) between the onset of each trunk muscle and the anterior deltoid formed the basis of the motor control analysis.
  
  
  RESULTS
  After training, disability was significantly lower in the SEG (d = 0.62, P = 0.018). Pain was reduced in both groups after training (P < 0.05), but was lower for the SEG (P < 0.05). Despite the general exercise group performing no specific trunk exercise, similar changes in trunk muscle onsets were observed in both groups after training.
  
  
  CONCLUSIONS
  SEG elicited significant reductions in self-rated disability and pain, whereas similar between-group changes in trunk muscle onsets were observed. The motor control adaptation seems to reflect a strategy of improved coordination between the trunk muscles with the unilateral shoulder movement. Trunk muscle onsets during rapid limb movement do not seem to be a valid mechanism of action for specific trunk exercise rehabilitation programs.
authors.affiliation: School of Science and Health, University of Western Sydney, Penrith, New South Wales, Australia.
authors.forename: Cristy
authors.initials: C
authors.lastname: Brooks
authors.forename: Suzanne
authors.initials: S
authors.lastname: Kennedy
authors.forename: Paul W M
authors.initials: PW
authors.lastname: Marshall
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D059031:Anticipation, Psychological; D001642:Bicycling; D001696:Biomechanical Phenomena; D059350:Chronic Pain / Q000175:diagnosis / Q000503:physiopathology / Q000523:psychology / Q000628:therapy*; D003071:Cognition; D004185:Disability Evaluation; D004576:Electromyography; D026241:Exercise Movement Techniques; D005081:Exercise Therapy; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000175:diagnosis / Q000503:physiopathology / Q000523:psychology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D018482:Muscle, Skeletal / Q000503:physiopathology*; D009517:New South Wales; D010147:Pain Measurement; D004856:Postural Balance; D011187:Posture; D011237:Predictive Value of Tests; D057566:Self Report; D013997:Time Factors; D060726:Torso; D016896:Treatment Outcome