Habitual physical activity and high-density lipoprotein cholesterol in men with primary hypercholesterolemia. The Lipid Research Clinics Coronary Primary Prevention Trial.

The association of habitual physical activity with plasma high-density lipoprotein (HDL) cholesterol and total triglyceride (TG) was examined in 7106 asymptomatic 35-59-year-old white men with primary type II hyperlipoproteinemia who attended the second screening visit of the Lipid Research Clinics Coronary Primary Prevention Trial. Subjects were rated by usual level of physical activity at work and outside of work and the frequency of strenuous physical labor or exercise. By each of these three criteria, physical activity was monotonically related to HDL cholesterol and TG: the most physically active men had the highest HDL cholesterol and lowest TG levels. With respect to physical activity outside of work, for example, mean HDL cholesterol and TG were 46.4 and 152.1 mg/dl, respectively, in the most active group, and 41.4 and 186.7 mg/dl in the most sedentary group. Physical activity remained significantly predictive of HDL cholesterol and TG when other known correlates of these plasma constituents--age, Quetelet index, plasma total cholesterol, cigarette smoking, alcohol intake, and clinic--were controlled individually by two-way analyses of variance or jointly by analysis of covariance. The association of physical activity with very low density lipoprotein cholesterol was parallel to but weaker than its association with TG. Low-density lipoprotein and total cholesterol were not significantly related to physical activity.