Summary: | Aims/hypothesis: Cardiorespiratory fitness (VO2 max) is an independent risk factor for type 2 diabetes; but in people at risk, factors influencing VO2 max are poorly understood. We tested the hypothesis that VO2 max is associated with diastolic function (SEVR%), (as diastolic function influences myocardial perfusion). Methods: 47 men and women with central obesity without diabetes were studied. We measured fitness (VO2 max) by treadmill testing and diastolic function (SEVR%) by pulse wave analysis. We measured other factors influencing this relationship [insulin sensitivity (M/I) by hyperinsulinemic euglycemic clamp; fatness by MRI and DEXA; physical activity energy expenditure (METS) by Sensewear Pro2; muscle microvascular exchange capacity (Kf) by venous plethysmography]. Results: Mean age [mean (SD) was 51 (9) years]. VO2 max was associated with SEVR% (r=0.50, p=0.001), fatness (r=-0.39, p=0.008) and HbA1c (r=-0.35, p=0.018) but not with M/I, METS or Kf. In regression modelling with age, sex, fatness, and SEVR% as explanatory variables, only age, sex and SEVR% were independently associated with V02 max (SEVR% - standardised B coefficient =0.37 ((95%CIs 0.003, 0.18), p=0.007). 46% of the variance in VO2 max (r2=0.46 p=0.0001) was identified by this model. Conclusions/interpretation: There was a strong, independent association between VO2 max and a measure of diastolic function in sedentary people with central obesity.
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