Serum lipid levels in female handball players were studied. A group of well trained female handball players, in comparison with a group of less active females, had a significantly lower level of triglyceride, higher levels of HDL-cholesterol and HDL2-Cholesterol subfractions, and higher apolipoprotein A-I and LCAT activities. The ratio of apolipoprotein B/apolipoprotein A-I, as an atherogenic index, was also significantly lower in the handball players. These results suggest that prolonged regular exercise such as handball training may produce favorable changes in serum lipids, thus helping to prevent and reduce the incidence of atherosclerosis.