"Bulking up" by athletes playing football and other sports may lead to an increased risk for cardiovascular disease, study findings suggest.

"Our work demonstrates a higher prevalence of metabolic syndrome, an established cardiovascular risk factor, among retired National Football League (NFL) linemen," said Dr. Marc A. Miller, of Mount Sinai Medical Center, in New York. Football linemen are commonly of large body size.

Metabolic syndrome refers to a combination of high blood pressure, low levels of 'good' cholesterol, high levels of blood lipids (fats), elevated blood sugar and high body weight.

When Miller and colleagues compared metabolic syndrome rates among 510 retired NFL players, they found that nearly 60 percent of linemen had metabolic syndrome, compared with 30 percent of those playing other positions.

Moreover, greater than 85 percent of the linemen were obese, compared to half of the non-linemen, the researchers report in the May 2008 issue of the American Journal of Cardiology.

Between February 2004 and June 2006, Miller and colleagues assessed metabolic syndrome factors among 164 linemen and 346 non-linemen who, at the time, were 54 years old on average. Overall, they had been NFL players for about 6 years and had been retired for about 25 years.

Miller notes that because previous research indicated increased rates of cardiovascular death among NFL linemen, he was not surprised to also find a higher prevalence of metabolic syndrome among football linemen.

"The NFL, like any employer, has an obligation to address the health concerns of its employees," Miller said. "Players will have to be educated about lifestyle modification in their post-professional years," he said.

Likewise, "Student athletes need to be educated about the potential long-term health consequences of 'bulking up' and should be discouraged from achieving unhealthy body weights," Miller said.