Influence of physical work on high density lipoprotein cholesterol: implications for the risk of coronary heart disease.

Physically trained individuals differ greatly from untrained counterparts in their high density lipoprotein (HDL) cholesterol blood levels. Such differences in turn may have implications for long-term preventive policies in coronary artery disease. In prospective studies, exercise programs in men, but seldom in women, have been shown to independently raise HDL cholesterol (HDL-C) concentrations in the blood. This evidence is of major interest because of the voluminous epidemiologic evidence for low blood levels of HDL-C as a risk factor for coronary heart disease. Experimental evidence is still missing to establish the efficacy of elevating blood HDL-C concentrations in actually reducing the risk of incident, or recurrent, coronary events. If the efficacy of elevating blood levels of HDL-C in ameliorating coronary prognosis is demonstrated, the recommendation for hygienic means, primarily physical exercise, will be reinforced. The role of physical training in elevating blood HDL-C is examined and plausible mechanisms for the observed experimental results are reviewed.