title: Open-loop feedback increases physical activity of youth.
abstract: OBJECTIVE
  The number of youth that meet activity guidelines is decreasing and easy access to reinforcing sedentary behaviors competes with increasing physical activity. In the laboratory, open-loop feedback that used pedometer activity counts to gain access to sedentary alternatives doubled physical activity. This study evaluated the influence of open-loop feedback and reinforcement on physical activity and television (TV) time in a small clinical trial.
  
  
  METHODS
  Children (8-12 yr old) were randomized to an open-loop feedback plus reinforcement intervention (N = 11) or no feedback, no reinforcement control (N = 7). Subjects wore an accelerometer for 6 wk and attended meetings to download the accelerometer. Accumulating physical activity counts gave subjects in the open-loop group access to TV time, controlled by a TV Allowance device, with 400 counts = 1 h of TV. The control group had no feedback for activity and free access to TV.
  
  
  RESULTS
  The open-loop group had a 24% increase in physical activity, which was greater (P = 0.02) than the control group. TV time of the open-loop group was reduced by 18% or 20 min x d(-1) whereas the control group increased by 13 min x d(-1), but these were not significant changes. The change in time spent watching television was directly related to the change in BMI z-score (r = 0.69, P = 0.002).
  
  
  CONCLUSIONS
  Open-loop feedback increases physical activity in children, thus helping children to achieve physical activity recommendations. Reductions in TV watching may reduce or minimize gains in body weight.
authors.affiliation: Division of Behavioral Medicine, Department of Pediatrics, State University of New York at Buffalo School of Medicine and Biomedical Sciences, Buffalo, NY 14214-3000, USA. roemmich@buffalo.edu
authors.forename: James N
authors.initials: JN
authors.lastname: Roemmich
authors.forename: Cathy M
authors.initials: CM
authors.lastname: Gurgol
authors.forename: Leonard H
authors.initials: LH
authors.lastname: Epstein
mesh_terms: D001676:Biofeedback, Psychology / Q000379:methods*; D002648:Child; D002652:Child Behavior / Q000502:physiology / Q000523:psychology*; D015444:Exercise / Q000502:physiology / Q000523:psychology*; D005260:Female; D015438:Health Behavior; D006801:Humans; D008019:Life Style; D008297:Male; D009042:Motivation; D009518:New York; D009765:Obesity / Q000517:prevention & control; D012054:Reinforcement, Psychology