Increased plasma HDL-cholesterol and apo A-1 in sedentary middle-aged men after physical conditioning.

Previous studies have demonstrated an inverse relationship between plasma high density lipoproteins (HDL) cholesterol and coronary heart disease risk. In the present study we investigated prospectively the effect of a moderate physical conditioning programme on plasma lipids and lipoproteins, especially HDL-cholesterol and apolipoprotein A-I (apo A-I), the major apoprotein of HDL. Healthy, sedentary, middle-aged men were randomly selected and assigned either to a training group (n = 24, age 40 +/- 3.4, mean +/- SD) or to a control group (n = 13, age 39 +/- 5.0). Training consisted of various indoor and outdoor sports activities 45 min/day, 3 times/week for 12 weeks at an intensity of approximately 80% of measured maximal oxygen uptake (VO2 max). The trained subjects were studied at 4, 8 and 12 weeks. The training increased VO2 max by 12% (P less than 0.01). Increases were observed in both apo A-I (10%, P less than 0.02) and HDL-cholesterol (8%, P less than 0.02) after training, with significant increases already after 4 and 8 weeks, respectively. Furthermore, decreases in total plasma cholesterol (5%, P less than 0.004) and plasma triglycerides (26%, P less than 0.003) were found without changes in body weight, body composition, cigarette smoking, alcohol consumption or the percentage composition of dietary intake. Fasting serum-insulin concentrations decreased significantly during training. No changes were noted in the control group. The present study demonstrates prospectively that moderate physical training can increase HDL.