High-density lipoprotein (HDL) cholesterol is called “the good cholesterol” for a reason. It’s because this type of cholesterol does the exact opposite of LDL cholesterol. Instead of depositing fat directly into the bloodstream where it can clog arteries, HDL carries cholesterol away. The cholesterol is deposited into the liver, where it is processed and removed from the body.
If a person has normal levels of HDL cholesterol, it stands to reason that they should be protected from heart disease risk factors. However, a new study is suggesting that normal levels of HDL may not be enough to prevent heart disease if the cholesterol isn’t functioning the way it’s supposed to be.
Sometimes HDL cholesterol can do its job of moving cholesterol to the liver, but it falls short in other areas. HDL also has roles to play in reducing inflammation and in acting as an antioxidant.
For their study, researchers from UCLA wanted to find out if HDL cholesterol behaves any differently in men who exercise regularly compared to those who are sedentary. A group of men who trained with weights regularly were compared to a group of men not participating in any active exercise. The researchers were hoping to find clues about “healthy” cholesterol, as previous research had already shown that exercise protects against heart disease risk factors.
The researchers recruited 90 men between the ages of 18 and 30 who were already participating in a steady exercise routine. These men were then divided into three groups: men who were lean and who weight-trained four times a week, overweight men who trained at least four times a week, and overweight men who didn’t follow any exercise program. Basic physical measurements were taken for all the participants. Height and weight were recorded, as was waist circumference, body composition, and blood pressure.
Next, the researchers measured the men’s muscle strength. They recorded carotid artery thickness and extracted a blood sample. The blood was analyzed for markers of heart disease including cholesterol, insulin, triglycerides, and C-reactive protein. It was at this point that the researchers tested the men’s cholesterol to see if it was functioning as an antioxidant. What do you think they found?
Sure enough, the researchers discovered that the men who exercised regularly had a higher chance of having “functional” cholesterol compared to the men who didn’t exercise. The research team was also able to determine that dysfunctional HDL boosted a man’s chances of having other risk factors for heart disease. These factors included high triglycerides and increased fat around the trunk area. This was true no matter what weight the men were. The researchers say this could mean that it’s not so much a healthy weight that’s important for maintaining healthy cholesterol function, but regular exercise such as weight training.
Follow the researchers’ suggestion and take up some weight training. Not only can you improve your strength and balance, but you could also significantly lower your risk for heart disease. Weight training could help to keep your HDL cholesterol functioning at peak performance levels, keeping LDL cholesterol in check, and reducing oxidative damage in the heart and circulatory system.
Source(s) for Today’s Article:
Roberts, C.K., et al., “Untrained young men have dysfunctional HDL compared with strength-trained men irrespective of body weight status.” J Appl Physiol (1985). October 2013; 115(7): 1,043-1,049.
“When It Comes to the Good Cholesterol, Fitness Trumps Weight,” Science Daily web site, Oct. 9, 2013; http://www.sciencedaily.com/releases/2013/10/131009125738.htm, last accessed Oct. 15, 2013.