Long workouts best for raising good cholesterol
Reuters - Thu May 31, 2007 6:12 PM ET

NEW YORK (Reuters Health) - People who want to boost their "good" HDL cholesterol levels with exercise will have to put in at least two hours of physical activity each week, an analysis of 25 studies shows.

And the longer each exercise session, the greater the effect, Dr. Satoru Kodama of Ochanomizu University in Tokyo and colleagues found. While the effect of exercise in increasing levels of HDL cholesterol is well known, studies have had varying results, Kodama and his team note in the Archives of Internal Medicine.

To clarify the relationship between the intensity and duration of exercise sessions and magnitude of HDL cholesterol reduction, the researchers analyzed 25 different randomized controlled trials looking at exercise and good cholesterol. Overall, the researchers found, exercisers increased their HDL cholesterol by a modest but significant 2.53 mg/dL, which equates to a roughly 5 percent drop in heart disease risk for men and a nearly 8 percent reduction for women.

In order for exercise to have an effect on HDL cholesterol, study participants had to expend at least 900 kilocalories a week in physical activity, equivalent to about 120 minutes of exercise. The researchers also found that the intensity of exercise or the frequency of exercise sessions didn't seem to matter, as long as exercise was performed consistently. However, the length of an exercise session did matter; for every 10 minutes longer a workout session lasted, there was an additional 1.4 mg/dL rise in good cholesterol.

The researchers also found that exercise had the greatest effect in increasing HDL cholesterol in people with body mass indexes less than 28 and those who had total cholesterol levels of 220 mg/dL or greater. While the effect of exercise identified in the study is likely smaller than that seen with HDL-boosting medications, including niacin and fibrates, the effect "is potentially of substantial importance to public health," the authors conclude.

SOURCE: Archives of Internal Medicine, May 28, 2007.
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- posted by Andy @ 5:25 PM