Too many Americans suffer from poor fitness and obesity. African-Americans are at particularly high risk, a new study shows.

Carl J. Lavie, MD, is co-director of cardiac rehabilitation and preventive cardiology at the Ochsner Clinic Foundation in New Orleans. Lavie and colleagues collected data on more than 5,000 men and women aged 52-74 who underwent treadmill heart stress tests at the Ochsner Clinic.

The major findings:

—On average, African-American men in the study were three years younger than the white men, yet African-American men's fitness capacity was 7% lower than that of white men. The difference is considered significant.

—On average, African-American women in the study were four years younger than the white women. Yet African-American women's fitness capacity was 3 percent lower than that of white women. This difference is not considered significant.

—African-American men were more likely to be obese than white men: 44 percent vs. 33 percent.

—African-American women were more likely to be obese than white women: 37 percent vs. 27 percent.

—African-American women were also more likely than white women to be severely obese: 19 percent vs. 11 percent.

"Even correcting for obesity, African-Americans are slightly less fit," Lavie tells WebMD. "Everyone in the country needs to be thinking about their weight and their fitness. Our data support [that] this is of even greater urgency in African-Americans."

Lavie's study appears in the December issue of the journal Chest.

Lavie notes that the best predictor of premature death is poor physical fitness. He points to studies showing that the best way people can reduce their risk of early death is to improve their exercise capacity.

"The message here is that both obesity and fitness are very important to all races and genders," he says. "But in African-Americans, we need even greater attention not only to reducing weight, but in improving fitness. The two go together but are separate, too."

Obstacles to Fitness

Sheila P. Davis, PhD, is professor of nursing at the University of Mississippi Medical Center in Jackson. She has studied African-American children living in the rural south and found high levels of obesity and low levels of fitness.

"Being African-American myself, I can conjecture about what is happening," Davis tells WebMD. "In the South, in terms of obesity, the differences are not that marked. To call it a black obesity problem is to miss the point — we have an obesity problem. In terms of fitness, we are more similar than dissimilar. There are no genetic differences. But there are things within the culture that we incorporate that might be responsible for some of the differences."

Unfortunately, she notes, many African-Americans face restraints on becoming more physically active. Children in poor communities attend schools that lack gyms and physical education teachers. And a person can't just put on running shoes and go for a jog or a walk in a community where personal safety is an issue.

"Those restraints exist," Davis says. "If they were removed, we would see more equalization in terms of fitness."

This does not excuse poor diets or sedentary lifestyles, Davis notes. She says there is a critical need for aggressive interventions to improve diet and exercise for African-American children and teens.

By Daniel J. DeNoon, reviewed by Brunilda Nazario, MD

SOURCES: Lavie, C.J. Chest, December 2004; vol 126: pp 1962-1968. Carl J. Lavie, MD, medical co-director, cardiac rehabilitation and preventive cardiology, Ochsner Clinic Foundation, New Orleans. Sheila P. Davis, PhD, professor of nursing, University of Mississippi Medical Center, Jackson.