Regular physical exercise is a deterrent of cardiovascular disease and its anti-atherogenic effects have been described in human studies [1].
On the contrary, physical inactivity has adverse consequences on cardiovascular risk, due in part to detrimental effects of serum lipoprotein concentration, namely LDL [3].
To investigate the effects of the amount and intensity of exercise on risk factors for cardiovascular disease, Bales et al. (2002) devised an experiment where overweight and obese men and women with mild-to-moderate dyslipidemia (elevation of lipids in the blood) were randomly assigned to a non-exercising control group or one of three training groups [2]:
- High-amount/high-intensity exercise, the caloric equivalent of 32 km of jogging per week;
- Low-amount/high-intensity exercise, the caloric equivalent of 19.2 km of jogging per week;
- Low-amount/moderate-intensity exercise, the caloric equivalent of 19.2 miles of walking per week.
– High-amount/high-intensity exercise significantly reduced the concentrations of LDL [2].
– The LDL cholesterol concentration decreased with increasing exercise levels [2].
– There was a clear beneficial effect on the HDL cholesterol concentration in the high-amount/high-intensity group. The lower amount of exercise had a smaller effect on these variables, with no apparent effect of the intensity of exercise [2].
– The data shows a clear effect of the amount of exercise on lipoproteins; it also shows that a relatively high amount of regular exercise — even in the absence of clinically significant weight loss — can significantly improve the overall lipoprotein profile [2].