title: Increasing overall physical activity and aerobic fitness is associated with improvements in metabolic risk: cohort analysis of the ProActive trial.
abstract: OBJECTIVE
  Our aim was to examine the association between change in physical activity energy expenditure (PAEE), total body movement (counts per day) and aerobic fitness (maximum oxygen consumption [VO2max] over 1 year and metabolic risk among individuals with a family history of diabetes.
  
  
  METHODS
  Three hundred and sixty-five offspring of people with type 2 diabetes underwent measurement of energy expenditure (PAEE measured using the flex heart rate method), total body movement (daily activity counts from accelerometry data), [VO2max] predicted from a submaximal graded treadmill exercise test and anthropometric and metabolic status at baseline and 1 year (n = 321) in the ProActive trial. Clustered metabolic risk was calculated by summing standardised values for waist circumference, fasting triacylglycerol, insulin and glucose, blood pressure and the inverse of HDL-cholesterol. Linear regression was used to quantify the association between changes in PAEE, total body movement and fitness and clustered metabolic risk at follow-up.
  
  
  RESULTS
  Participants increased their activity by 0.01 units PAEE kJ kg(-1) day(-1) over 1 year. Total body movement increased by an average of 9,848 counts per day. Change in total body movement (beta = -0.066, p = 0.004) and fitness (beta = -0.056, p = 0.003) was associated with clustered metabolic risk at follow-up, independently of age, sex, smoking status, socioeconomic status and baseline metabolic score.
  
  
  CONCLUSIONS
  Small increases in activity and fitness were associated with a reduction in clustered metabolic risk in this cohort of carefully characterised at-risk individuals. Further research to quantify the reduction in risk of type 2 diabetes associated with feasible changes in these variables should inform preventive interventions.
authors.affiliation: Medical Research Council Epidemiology Unit, Institute of Metabolic Science, Addenbrooke's Hospital, P.O. Box 285, Hills Road, Cambridge, CB2 0QQ, UK.
authors.forename: R K
authors.initials: RK
authors.lastname: Simmons
authors.forename: S J
authors.initials: SJ
authors.lastname: Griffin
authors.forename: R
authors.initials: R
authors.lastname: Steele
authors.forename: N J
authors.initials: NJ
authors.lastname: Wareham
authors.forename: U
authors.initials: U
authors.lastname: Ekelund
mesh_terms: D000328:Adult; D000332:Aerobiosis; D015992:Body Mass Index; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics* / Q000517:prevention & control; D004734:Energy Metabolism; D019317:Evidence-Based Medicine; D015444:Exercise; D005080:Exercise Test; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000453:epidemiology; D008875:Middle Aged; D009043:Motor Activity; D010101:Oxygen Consumption; D010809:Physical Fitness