When it comes to the prevention of heart disease, a high HDL (good cholesterol) has always been thought to provide some protection against the development of a heart attack which is one of the many reasons your family doctor may have urged you to get out and exercise on a daily basis. But as far as exercise and HDL, how much exercise does it really take to increase HDL and how effective is it at raising the levels of this good cholesterol? Up until the present time, the amount of exercise needed to do the important job of raising HDL levels to prevent heart disease has not been firmly quantified.
Recently a comprehensive analysis called a meta-analysis was performed on thirty-five previous studies that addressed the issue of exercise and HDL in an attempt to answer the question of how much exercise is needed to actually raise HDL levels. The results were published in the Archives of Internal Medicine, May 28, 2007. The meta-analysis scrutinized about 1400 subjects who had taken part in previous trials looking at exercise and HDL in an attempt to quantify and further clarify the role exercise plays.
The researchers found after exercise training, the HDL levels of the exercise subjects were 2.53 mg/dl higher than subjects assigned to the control group who didn’t exercise, a rather modest gain. Furthermore, HDL levels only increased in those subjects who exercised at least one hundred and twenty minutes per week for thirty minutes per session. It didn’t appear that exercising more frequently or at a higher level of intensity improved HDL levels any further in the test subjects.
Analysis of Results:
It appears that aerobic exercise sessions of at least thirty minutes in length four times per week are required to cause a significant rise in HDL levels. Exercise sessions less than thirty minutes don’t appear to have a beneficial effect on HDL levels nor does excessively strenuous or very frequent exercise sessions appear to have any additional positive benefit on HDL. The overall effect of aerobic exercise on HDL is rather modest.
The bottom line is you’ll need to exercise aerobically at least thirty minutes at a stretch and do it at least four times a week to see any real effect on HDL levels. In addition, the effects of exercise alone on HDL levels may not be as dramatic as originally thought. This shouldn’t discourage anyone who’s trying to use exercise to help reduce the risk of heart disease. Exercise has been shown to have beneficial effects on a variety of cardiac risk factors such as lowering blood pressure and keeping weight under control. It should continue to be a part of any serious heart disease prevention program despite the more limited role that exercise and HDL may play.
- Archives of Internal Medicine: May 28, 2007