title: Accelerometers and pedometers: methodology and clinical application.
abstract: OBJECTIVE
  The relationship between physical activity and health varies considerably, partly due to the difficulty of assessing physical activity accurately. This review examines recent literature on the validation of movement sensors to assess habitual physical activity. Recommendations are given for the use of movement sensors during free-living conditions and methods of data analysis and interpretation are discussed.
  
  
  RESULTS
  Recent progress in physical-activity research includes detailed comparative studies of different monitor brands. The move away from using linear-regression equations and the use of novel data-analysis strategies is increasing the accuracy with which energy expenditure can be estimated from accelerometry. New technologies, including the combination of accelerometry with the measurement of physiological parameters, have great potential for the increased accuracy of physical-activity assessment.
  
  
  CONCLUSIONS
  Accelerometry is able to adequately assess physical activity and its association with health outcomes but currently methods have limited accuracy for the estimation of free-living energy expenditure. Pedometers provide an inexpensive overall measure of physical activity but are unable to assess intensity, frequency and duration of activity or to estimate energy expenditure. Interpretation of monitor output is best kept as close to the measurement domain as possible.
authors: Medical Research Council Epidemiology Unit, Cambridge, UK.
authors: Kirsten
authors: K
authors: Corder
authors: Søren
authors: S
authors: Brage
authors: Ulf
authors: U
authors: Ekelund
mesh_terms: D000203:Activities of Daily Living; D004734:Energy Metabolism / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D006304:Health Status; D006801:Humans; D008124:Locomotion; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods / Q000592:standards; D009043:Motor Activity / Q000502:physiology; D010809:Physical Fitness / Q000502:physiology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity