Even for the Overweight, Exercise Helps the Heart
- Reported, February 08, 2012
Study finds changes in physical fitness affect disease risk at any
weight.Getting and staying physically fit might help fend off heart disease even
if you've put on a few pounds, new research suggests.
"If you would like to reduce the risk of cardiovascular disease, you want to be
cautious about weight gain but at the same time concerned about maintaining or
improving fitness," said study author Duck-chul Lee, a research fellow at the
University of South Carolina, in Columbia.
Maintaining or improving fitness could somewhat counteract the increased risk of
fat gain, researchers found. On the other hand, reducing body fat helped make up
for the added heart-disease risk linked with losing fitness.
The study is published in the Feb. 14 issue of the Journal of the American
College of Cardiology.
Experts have long known that both fatness and fitness affect heart-disease risk
factors. However, the researcher say the new study is one of the first to look
at how a change in fitness or fatness (or both) affects the development of these
risk factors later. The new analysis allowed for fitness and fatness to be
adjusted for each other, which isn't taken into account in many studies.
Lee and his colleague followed 3,148 healthy adults enrolled in the Aerobics
Center Longitudinal Study. All received at least three extensive medical exams
from 1979 to 2006 at the Cooper Clinic, in Dallas.
They looked for any of three risk factors: high blood pressure, high cholesterol
or metabolic syndrome.
Metabolic syndrome is a group of signs that raise the risk of diabetes and heart
disease. To be diagnosed, someone must have at least three of the five signs:
large waist (abdominal obesity), high triglycerides, low "good" cholesterol,
high blood pressure and high fasting blood sugar.
Researchers measured fitness with a treadmill test and calculated body fatness
with body-mass index (BMI) -- which takes height and weight into account -- and
skinfold testing. Researchers looked at changes over time.
At the end of the study, 752 participants had high blood pressure, 426 had
metabolic syndrome and 597 had high cholesterol.
Those who maintained or improved fitness over time had a lower risk of
developing any of the three risk factors. Those who maintained fitness has a 24
percent lower risk of high blood pressure, 38 percent lower risk of metabolic
syndrome and 25 percent lower risk of high cholesterol. Those who gained fitness
reduced their risk of each about the same or slightly more.
Those who gained body fat were more apt to develop one of the risk factors than
those who lost fat. Gaining fat put the men and women at 24 percent higher risk
of getting high blood pressure, 52 percent higher risk of getting metabolic
syndrome and 41 percent higher risk of high cholesterol.
Maintaining or improving fitness modified but did not eliminate the increased
risk caused by fat gain. And reducing fat seemed to offset part of the higher
risk linked with losing fitness.
Best possible scenario? "If you lose fat and gain or maintain fitness, you have
the lowest risk of all three risk factors," Lee said.
Being fit and not being fat work independently to reduce risk factors, Lee said.
If you can't improve with fitness or fatness? Try to at least maintain, he said.
The study provides some good news, said Dr. Suzanne Steinbaum, director of Women
and Heart Disease at Lenox Hill Hospital, in New York City. She is also a
spokesperson for the American Heart Association's "Go Red for Women" campaign.
The study, she said, seems to be saying: "If you are fit, it sort of gets rid of
some of the risk of being fat. If you are less fat, it gets rid of some of the
risks of being less fit than you should be."
She sees this take-home message: "If you are going to be overweight, you have to
be fit. Ultimately you have to pay attention if not to both at least to one."