Fitness, Fatness, and Serum Cholesterol: An Epidemiological Study of an Entire Community

A modification of the Harvard Step Test was administered to over 5000 males and females, age 10–69, in Tecumseh, Michigan. The ECG was recorded during and after the exercise. A blood sample was drawn for serum total cholesterol (Abell Method) on the same day the exercise test was given. Four skinfolds as a measure of body fatness were also taken. Heart rate response to the standardized exercise test is an estimate of capacity for muscular work. It was the purpose of this analysis to study the relationship of serum cholesterol to heart rate response to exercise. All analyses were done in age and sex-specific groups. The correlation coefficients were low and in about a third of the groups, statistically significant. This suggests that poor fitness for work (high heart rate) was related, albeit weakly, to higher serum cholesterol. However, there was a positive relationship between body fatness on the one hand and serum cholesterol and heart rate response to exercise on the other. When the effect of body fatness was eliminated there was essentially no relationship between this estimate of work capacity and serum total cholesterol.