Relationship between exercise and cholesterol levels
It is well known that exercise reduces the risk of cardiovascular disease. It is possible that this effect is mediated, in part, by an improvement in the lipid profile.
Researchers at Duke University have investigated the effects of the amount of exercise training required to optimize the lipid profile in sedentary, overweight people with mild to moderate dyslipidemia (abnormal lipid profile).
The study subjects were randomly assigned to participate in a control group (no exercise) or in three exercise groups of varying intensity. Lipoprotein analysis was performed at the completion of the study.
The study authors demonstrated that there was a beneficial effect of exercise on a variety of lipid and lipoprotein variables, seen most clearly with the high amount of high-intensity exercise. The high amount of exercise resulted in greater improvements than did the lower amounts of exercise and was always superior to the control group who did not exercise.
The study concluded that the improvement in lipid profiles were related to the amount of activity and not to the intensity of exercise or improvement in fitness.
The message from this study is clear: exercise regularly ("high amount") without regard to the intensity of the exercise. Regular walking, regular jogging, regular rowing, regular aerobics and so on. Regular exercise is key to improving your lipid profile and cardiovascular fitness.
Effects of the Amount and Intensity of Exercise on Plasma Lipoproteins, New England Journal of Medicine 347:1483-92
(Article was modified from my original contribution to my website.)