Bad cholesterol’s good for big muscles

TEXAS A&M (US) — The more LDL, or “bad cholesterol,” you have, the more muscle you build during resistance training.

A new study found that after fairly vigorous workouts, adults who were in generally good health, but not normally physically active, gained the most muscle mass but also had the highest levels of the “bad” cholesterol—low-density lipoprotein (LDL).

“It shows that you do need a certain amount of LDL to gain more muscle mass,” says Steve Riechman, assistant professor of health and kinesiology at Texas A&M University.

“There’s no doubt you need both, the LDL and the HDL,  and the truth is, it (cholesterol) is all good.  You simply can’t remove all the “bad” cholesterol from your body without serious problems occurring.”

The research is reported in the Journal of Gerontology.

Cholesterol is found in all humans and is a type of fat around the body.  Total cholesterol level is comprised of LDL (low-density lipoprotein) and HDL (high-density lipoprotein) cholesterol.

LDL is almost always referred to as the bad cholesterol because it tends to build up in the walls of arteries, causing a slowing of the blood flow which often leads to heart disease and heart attacks. HDL, usually called the good cholesterol, often helps remove cholesterol from arteries.

“But here is where people tend to get things wrong,” Riechman says. “LDL serves a very useful purpose.  It acts as a warning sign that something is wrong and it signals the body to these warning signs.  It does its job the way it is supposed to.

“People often say, ‘I want to get rid of all my bad (LDL) cholesterol,’ but the fact is, if you did so, you would die. Everyone needs a certain amount of both LDL and HDL in their bodies.  We need to change this idea of LDL always being the evil thing7mdash;we all need it, and we need it to do its job.”

According to the American Heart Association, about 36 million American adults have high cholesterol levels.

“Our tissues need cholesterol, and LDL delivers it. HDL, the good cholesterol, cleans up after the repair is done. And the more LDL you have in your blood, the better you are able to build muscle during resistance training.”

The findings could be helpful in studying sarcopenia, a condition where muscle is lost due to aging. Previous studies show muscle is usually lost at a rate of 5 percent per decade after the age of 40.  After the age of 60, the prevalence of moderate to severe sarcopenia is found in about 65 percent of all men and about 30 percent of all women, and accounts for more than $18  billion of health care costs in the United States.

“The bottom line is that LDL, the bad cholesterol, serves as a reminder that something is wrong and we need to find out what it is. It gives us warning signs. Is smoking the problem, is it diet, is it lack of exercise that a person’s cholesterol is too high?

“It plays a very useful role, does the job it was intended to do, and we need to back off by always calling it bad cholesterol because it is not totally bad.”

Researchers from Johns Hopkins University, the University of Pittsburgh, and Kent State University contributed to the study.

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