title: A prospective study of cardiorespiratory fitness and risk of type 2 diabetes in women.
abstract: OBJECTIVE
  The purpose of this study was to determine the independent and joint associations of cardiorespiratory fitness (CRF) and BMI with the incidence of type 2 diabetes in women.
  
  
  METHODS
  An observational cohort of 6,249 women aged 20-79 years was free of baseline cardiovascular disease, cancer, and diabetes. CRF was measured using a maximal treadmill exercise test. BMI was computed from measured height and weight. The incidence of type 2 diabetes was identified primarily by 1997 American Diabetes Association criteria.
  
  
  RESULTS
  During a 17-year follow-up, 143 cases of type 2 diabetes occurred. Compared with the least fit third, the multivariate (including BMI)-adjusted hazard ratio (HR) (95% CI) was 0.86 (0.59-1.25) for the middle third and 0.61 (0.38-0.96) for the upper third of CRF. For BMI, the multivariate (including CRF)-adjusted HR (95% CI) was 2.34 (1.55-3.54) for overweight individuals and 3.70 (2.12-6.44) for obese individuals, compared with normal-weight patients. In the combined analyses, overweight/obese unfit (the lowest one-third of CRF) women had significantly higher risks compared with normal-weight fit (the upper two-thirds of CRF) women.
  
  
  CONCLUSIONS
  Low CRF and higher BMI were independently associated with incident type 2 diabetes. The protective effect of CRF was observed in individuals who were overweight or obese, but CRF did not eliminate the increased risk in these groups. These findings underscore the critical importance of promoting regular physical activity and maintaining normal weight for diabetes prevention.
authors: Department of Exercise Science, University of South Carolina, Columbia, South Carolina, USA. msui@gwm.sc.edu
authors: Xuemei
authors: X
authors: Sui
authors: Steven P
authors: SP
authors: Hooker
authors: I-Min
authors: IM
authors: Lee
authors: Timothy S
authors: TS
authors: Church
authors: Natalie
authors: N
authors: Colabianchi
authors: Chong-Do
authors: CD
authors: Lee
authors: Steven N
authors: SN
authors: Blair
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D002320:Cardiovascular Physiological Phenomena; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D015999:Multivariate Analysis; D010809:Physical Fitness / Q000502:physiology*; D011446:Prospective Studies; D012143:Respiratory Physiological Phenomena; D012307:Risk Factors; D013781:Texas / Q000453:epidemiology