title: The effect of frequency of kinetic feedback on learning an isometric force production task in nondisabled subjects.
abstract: OBJECTIVE
  The purpose of this study was to investigate the effects of kinetic feedback frequency and concurrent kinetic feedback on the performance and learning of an isometric force production task in young, nondisabled adults.
  
  
  METHODS
  Twenty-four nondisabled, right-hand-dominant adults (18 male, 6 female), aged 19 to 33 years (mean = 22.5, SD = 4.1), participated in this study.
  
  
  METHODS
  Eight subjects in each of three kinetic feedback groups performed an isometric elbow extension task in an attempt to minimize error between their effort and a force template over a 5-second period. Feedback was provided (1) concurrently with and after each attempt (concurrent feedback), (2) after each attempt (100% feedback), or (3) after every other attempt (50% feedback). Immediate and delayed (48-hour) retention tests were performed without feedback. Separate analyses of variance for repeated measures were used to compare task error among the three feedback groups for acquisition, immediate retention, and delayed retention trials.
  
  
  RESULTS
  A significant interaction was found during the acquisition trial blocks, but at each trial block, subjects in the concurrent feedback group exhibited less error than did the subjects in either the 50% or 100% feedback group during the acquisition trials. For the immediate retention test, the 50% and 100% feedback groups exhibited 58% and 39% less error, respectively, than did the concurrent group. For the delayed retention test, the 50% and 100% feedback groups exhibited 52% and 26% less error, respectively, than did the concurrent group. In the immediate and delayed retention tests, subjects in the 50% feedback group displayed less error (31% and 36%, respectively) than did the 100% feedback group.
  
  
  CONCLUSIONS
  When permanent changes in the performance of a motor task are desired, concurrent feedback about task performance may be less desirable than feedback that is provided after the task has been completed. In addition, when feedback was used after the task had been completed, a lower frequency of feedback resulted in more permanent changes in the subjects' ability to complete the task.
authors.affiliation: Department of Physical Therapy, College of Health, Social, and Public Services, Eastern Washington University, Cheney, WA 99004.
authors.forename: D W
authors.initials: DW
authors.lastname: Vander Linden
authors.forename: J H
authors.initials: JH
authors.lastname: Cauraugh
authors.forename: T A
authors.initials: TA
authors.lastname: Greene
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001676:Biofeedback, Psychology; D004550:Elbow / Q000502:physiology*; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D007537:Isometric Contraction; D007700:Kinetics; D007858:Learning; D008297:Male; D009048:Motor Skills; D009991:Oscillometry; D026741:Physical Therapy Modalities / Q000379:methods / Q000592:standards; D011597:Psychomotor Performance