Cross-sectional relationship of sub-maximal aerobic capacity and obesity with coronary risk factors in Japanese women

Abstract

  The purpose of this study was to clarify the cross-sectional relationship between 50%VO₂max/wt (ml/kg/min) predicted by the one-point method (1PM50%VO₂max/wt) and coronary risk factors (CRFs) in Japanese women, according to body mass index (BMI).
  The study subjects were 1908 women aged 30—59 years with a BMI of 18.5—34.9 kg/m²; none had been taking medicines for hypertension, dyslipidemia, or diabetes. Work rate (WR) corresponding to the age-estimated heart rate at 50%VO₂max (HR@50%VO₂max=38−age/2; bpm) was calculated from the formula WR corresponding to HR at 50%VO₂max=WR at exercise/(HR during exercise/HR at 50%VO₂max). 1PM50%VO₂max/wt was calculated by substituting WR for the metabolic formula given in the guidelines for exercise testing and prescription published by the American College of Sports Medicine. The subjects were categorized on the basis of BMI as obese (Ob, BMI 25.0—34.9 kgm²) or normal weight (NW, BMI 18.5—24.9 kgm²). Each weight group was then categorized on the basis of 1PM50%VO₂max/wt as low fitness (LF, 1PM50%VO₂max/wt<4 METs) or high fitness (HF, 1PM50%VO₂max/wt>=4 METs). Systolic blood pressure, diastolic blood pressure, total cholesterol, triglyceride, high-density lipoprotein cholesterol, fasting blood sugar and HbA1c were measured as CRFs. Logistic regression analysis was conducted to calculate the odds ratios for each group.
  Our findings confirmed that the odds ratio (OR) for having abnormal CRF values was significantly lower in the NW+HF, NW+LF and Ob+HF groups than in the Ob+LF group. Furthermore, the OR was lower at a higher fitness level, regardless of the adjusted BMI. In conclusion, the present findings suggest that a higher submaximal aerobic capacity has a beneficial effect on CRFs independent of obesity.