But the surprising results should not be taken as a greenlight for unrestrained eating, the researchers caution. Being trim and fit is best, says cardiologist Dr. Timothy R. Wessel, an investigator at UF’s Health Science Center and the report’s lead author. Still, the study suggests body weight may not be as crucial for heart health as exercise.

“Our study accepts the fact that obesity is a cardiovascular risk factor,” Wessel said. “It is and has been shown to be so in multiple studies. But what this study suggests is that simply modifying weight without modifying your physical fitness level is not addressing a perhaps more important risk condition for cardiovascular events; that is, poor physical fitness.”

The researchers say their results clearly emphasize the need to assess an individual’s activity levels as a routine part of the medical exam. A 12-item questionnaire used in the study to assess the women’s perceived level of fitness is a powerful tool that easily could be adopted by physicians to identify patients prone to future problems, said Dr. Carl J. Pepine, chief of cardiovascular medicine at UF’s College of Medicine and the paper’s senior author.

The findings come as experts note a staggering two-thirds of U.S. adults are overweight and more than a third are obese. Obesity heightens the risk of heart-related problems, in part because it is associated with the development of artery-clogging fat deposits and malfunctioning blood vessels. But the UF study is important because it shows that a patient’s own perceived physical activity level alone appears to predict heart disease risk, even after accounting for weight, traditional cardiovascular risk factors and body measurements, such as body mass index, waist circumference or waist-to-hip ratio, Pepine said.

“There’s no doubt that increasing levels of obesity are associated with many potential medical problems over time, not the least of which are cardiovascular disease, diabetes and hypertension. The latter conditions can lead to serious heart disease,” he said. “But it seems from this research that at least women may be able to negate some of the adverse effects of obesity and being overweight by increasing their levels of fitness.”

UF researchers studied about 900 middle-aged women who were enrolled in the National Heart, Lung and Blood Institute-sponsored Women’s Ischemia Syndrome Evaluation, or WISE. All had symptoms suggestive of reduced blood flow to the heart. WISE seeks to define the prevalence, extent, severity and complexity of heart disease in women and also aims to find ways to better predict it.

About 41 percent of study participants were obese, defined as a body mass index greater than or equal to 30; all told, three-quarters were overweight. A little more than half had high blood pressure or high cholesterol. Two-thirds had no evidence of obstructed arteries on coronary angiograms.

The women completed a questionnaire that assessed measures of fitness, including whether they participated in light sports, could climb a flight of stairs, carry groceries up stairs or run a short distance. Results are designed to express the questionnaire findings in terms of the standard exercise treadmill test performance commonly used to gauge heart health.

“In the study we used the term 'physically fit' not to describe trained Olympic athletes but to correspond to the day-to-day activities many of us do,” Wessel said.

The UF researchers found that lower fitness levels were associated with a higher-than-expected rate of heart attack, stroke, hospitalization and death during follow-up. Overall, about half the study participants developed heart-related adverse events.

Of those, about 28 percent of the women classified as obese yet fit experienced heart problems, just slightly more than the 24 percent of women who were lean and fit. In contrast, a startling 43 percent of those who were lean but unfit developed events, comparable to the 42 percent of those who were obese and unfit who also fared poorly.

“The suggestion is that it’s actually better to be in shape even if you are obese. If you were out of shape, being thin did not offer protection,” Wessel said. “Just being at a lower body mass index or some other measure of obesity is not as important as better fitness or having higher activity or exercise capacity.”

However, many popular approaches to tackling obesity, such as diets, focus on weight loss alone and fail to stress efforts to improve physical fitness, he said.

“It’s alarming to see recent weight-loss trends that involve following a diet plan and don’t emphasize changing physical activity or fitness at all,” said Wessel, adding that the American Heart Association recommends women participate in at least 30 minutes of moderate e {mos_sb_discuss:2}