This study presents an original approach to the effect of regular sporting activity on the metabolism of lipids. We have examined the physiological variations of lipoparticles (Lp) AI, Lp B:CIII, Lp B:E, Lp (a) and the principal lipid markers in 21 high-level rugby players and men of the same age group who take part in no sporting activity (reference group; n = 35). The analysis showed a paradoxical decrease in the high-density lipoprotein fraction of cholesterol (P < 0.05) and in apolipoprotein AI (P < 0.0001), and an increase in the apoprotein B/apoprotein AI ratio in the sportsmen, compared with the reference group. According to these results, physical activity seems to have only a slight influence on anti-atherogenic serum markers. However, the drop in Lp B:E (P < 0.0001) and the static level of Lp AI in the sportsmen indicate a favourable effect of sport on these lipoparticles. The results of this study also highlight the importance of triglycerides and their metabolism. In fact, the lower triglyceride levels (P < 0.05) of the sportsmen justify special attention to diet, especially during a period of competition.