title: Postprandial Metabolic Effects of Accelerometer Measured Spontaneous Low-Level Activity.
abstract: BACKGROUND
  Interrupting sedentary time induces improvements in glucose metabolism; however, it is unclear how much activity is required to reduce the negative effects of prolonged sitting.
  
  
  METHODS
  Sixty-six participants sat continuously for 9 hours except for required bathroom breaks. Participants were fed meal replacement beverages at 60, 240 and 420 min. Blood samples were obtained hourly for 9 hours, with additional samples collected 30 and 45 min after each feeding. Responses were calculated as incremental area under the curve (iAUC) for plasma glucose, insulin and triglyceride. Participants wore a triaxial accelerometer and a heart rate monitor. Energy expenditure was estimated using indirect calorimetry.
  
  
  RESULTS
  After controlling for age, sex and BMI, every 100 count increase in accelerometer derived total movement was associated with a 0.06 mmol·L-1·9 hours decrease in glucose iAUC (95% CI 0.004-0.1; P = .035), but not associated with changes in insulin or triglyceride iAUC. Every 1 bpm increase in mean heart rate was associated with a 0.76 mmol·L-1·9 hours increase in triglyceride iAUC (95% CI 0.13-1.38).
  
  
  CONCLUSIONS
  Accelerometer measured movement during periods of prolonged sitting can result in minor improvements in postprandial glucose metabolism, but not lipid metabolism.
authors.affiliation: Dept of Human Nutrition, University of Otago, Dunedin, Otago, New Zealand.
authors.forename: Meredith C
authors.initials: MC
authors.lastname: Peddie
authors.forename: Claire
authors.initials: C
authors.lastname: Cameron
authors.forename: Nancy
authors.initials: N
authors.lastname: Rehrer
authors.forename: Tracy
authors.initials: T
authors.lastname: Perry
mesh_terms: D061725:Accelerometry / Q000379:methods*; D000328:Adult; D019540:Area Under Curve; D001786:Blood Glucose / Q000032:analysis; D002153:Calorimetry, Indirect; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D007328:Insulin / Q000097:blood; D050356:Lipid Metabolism / Q000502:physiology*; D008297:Male; D019518:Postprandial Period / Q000502:physiology*; D011187:Posture / Q000502:physiology; D057185:Sedentary Behavior; D014280:Triglycerides / Q000097:blood
chemical_list: D001786:Blood Glucose; D007328:Insulin; D014280:Triglycerides; D005947:Glucose