Men who didn't exercise more likely to have dysfunctional HDL

There's no question that high levels of good cholesterol-also known as high-density lipoprotein (HDL)-seem to be protective against heart disease. Rather than depositing fat into the blood vessels the way the "bad" cholesterol (low-density lipoprotein (LDL)) does, HDL appears to carry cholesterol away from blood vessels to the liver. From there, the liver processes it for removal from the body.

However, adequate levels of HDL might not be enough. Several recent studies have suggested that many cases of heart disease occur in people with normal levels of HDL cholesterol. Consequently, some researchers believe that even if people have adequate amounts of HDL cholesterol, it might not work well. Such HDL may not fulfill this molecule's other important duties in the body, such as reducing inflammation and acting as an antioxidant.

Because exercise has the potential to protect against heart disease in a variety of ways, Christian K. Roberts and his colleagues at UCLA tested whether HDL in men who weight trained regularly behaved in a healthier way than HDL in sedentary men. They found that the men who didn't exercise were more likely than those who weight trained to have dysfunctional HDL. Having faulty HDL was associated with numerous other risk factors for heart disease, including high triglycerides and a higher trunk fat mass. This finding held true regardless of the men's weight, which suggests that maintaining a "healthy" weight isn't as important for healthy cholesterol function as being active by regularly performing strength training.