title: Quantifying physical activity via pedometry in elementary physical education.
abstract: OBJECTIVE
  The objective of this study was to determine a pedometer steps per minute standard for quantifying the lesson time that first- and second-grade physical education students spent in moderate to vigorous physical activity (MVPA).
  
  
  METHODS
  The sample was divided into validation (N = 246) and cross-validation (N = 123) samples using the holdout technique. Using the criterion test model, steps per minute cut points were empirically and judgmentally determined. C-SOFIT systematic observation was the criterion instrument and pedometry was the predictor instrument. Data were collected from 45 physical education lessons implemented in six schools. The three-step analytic procedure of computing mastery/nonmastery outcome probabilities, phi coefficients, and error proportions was used to determine the optimal steps per minute cut point for quantifying 33.33% of the physical education lesson time engaged in MVPA within a 30 class.
  
  
  RESULTS
  Steps per minute was highly correlated with observation (r = 0.74-0.86, P < 0.0001). Five steps per minute scores that were accurate indicators of 33.33% of the class time engaged in MVPA in the validation sample were accurate indicators of steps per minute in the cross-validation sample. The optimal steps per minute cut point ranged from 60.00 to 63.00, which is equivalent to 1800-1890 steps in a 30-min physical education class.
  
  
  CONCLUSIONS
  Data supports the use of pedometry steps per minute values as an accurate indicator of MVPA. Pedometry demonstrates promise as a viable large-scale surveillance instrument for measuring MVPA in physical education.
authors.affiliation: Department of Physical Education, Health and Sport Studies, Miami University, Oxford, OH, USA. scruggpw@muohio.edu
authors.forename: Philip W
authors.initials: PW
authors.lastname: Scruggs
authors.forename: Sandy K
authors.initials: SK
authors.lastname: Beveridge
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Eisenman
authors.forename: Doris L
authors.initials: DL
authors.lastname: Watson
authors.forename: Barry B
authors.initials: BB
authors.lastname: Shultz
authors.forename: Lynda B
authors.initials: LB
authors.lastname: Ransdell
mesh_terms: D002648:Child; D004734:Energy Metabolism; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D008991:Monitoring, Physiologic / Q000295:instrumentation*; D010806:Physical Education and Training; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016138:Walking