The effects of running mileage and duration on plasma lipoprotein levels

Abstract

Healthy, sedentary men [81] aged 30-55 yr were randomly assigned to supervised running [number] (n = 48) or to sedentary control groups (n = 33) and followed up in a 1-yr trial. Measurements of plasma lipoproteins, fitness and percent body fat were made at 3-mo. intervals. Cross-sectional studies of lipoprotein concentrations in exercisers may be biased by a self-selection effect, since study participants with initially higher high-density lipoprotein cholesterol (HDL-C) and lower triglyceride concentrations were more easily persuaded to run more miles. Plasma concentrations of HDL-C and low-density lipoprotein cholesterol (LDL-C) generally did not begin to change until a threshold exercise level (10 mi run/wk) was maintained for at least 9 mo. Fitness increased and percent body fat decreased sooner and at lower exercise levels than required for HDL-C and LDL-C concentration changes.