DALLAS — Is it better from the standpoint of cardiovascular risk to be fat and fit, or lean and unfit?
That's a question in the minds of many roly-poly regular exercisers and skinny couch potatoes who are contemplating a lifestyle change. And Dr. Charles B. Eaton provided the answer at the annual scientific sessions of the American Heart Association.
Young adults who are lean and have poor cardiorespiratory fitness have a coronary heart disease risk profile that is clearly better than that of overweight individuals with high fitness. But the best CHD risk factor profiles of all belong to individuals with high fitness and a normal body mass index (BMI), according to Dr. Eaton of Brown University, Providence, R.I.
He analyzed cross-sectional data on a representative sample of 2,178 Americans aged 20–49 years who were included in the National Health and Nutrition Examination Survey for 1999–2002. Dr. Eaton categorized the subjects as having low, medium, or high cardiorespiratory fitness based upon their estimated VO2 max compared with age- and gender-specific norms. He further cross-stratified participants as normal-weight—meaning a body mass index of less than 25 kg/m
When Dr. Eaton plugged in data on each subject's total cholesterol, HDL, blood glucose, and insulin levels, as well as insulin resistance and systolic blood pressure, the composite CHD risk factor profile that emerged shot down the hypothesis that fat but fit is better than lean but unfit.