Healthy young hearts

U researcher combats childhood obesity

Associate professor of kinesiology Donald Dengel has found that exercise improves vascular health in overweight children.

Photo by Patrick O'Leary

From M, winter 2007

It's no secret that the United States is in the midst of a childhood obesity epidemic--an astounding one-third of our children, nearly nine million children are at risk for obesity-related illnesses, including formerly adult-only diseases like hypertension, elevated cholesterol, Type 2 diabetes, heart disease, and stroke.

Donald Dengel of the College of Education and Human Development studies cardiovascular health in overweight children--looking for promising early interventions that might give them a healthy future.

Dengel, associate professor of kinesiology and co-director of the General Clinic Research Center's Body Composition Human Performance Laboratory, focuses much of his research on the endothelium--or lining of the blood vessel--looking for signs of dysfunction that lead cardiovascular disease, and working on ways to improve the endothelia of overweight children.

"If we think about schools as just a place where intellectual learning happens, we will continue to add to the problem of childhood overweight and obesity," Dengel says.

His recent research followed a group of overweight children with endothelial dysfunction as they participated in four-times-weekly exercise sessions on a stationary bike. Their peers in the control group did not change their exercise habits.

After just eight weeks, the exercise group improved dramatically in vascular health, with endothelial functions returning to normal. This is not the case in adults, who can improve endothelial function with exercise, but not totally reverse the damage. In addition, the kids improved their physical fitness and increased their HDL cholesterol (the good cholesterol).

The study participants who exercised didn't lose weight or reduce body fat, but from a vascular health standpoint, Dengel says, weight loss appears to be less important than exercise. "If we get kids to exercise early enough--regardless of being overweight--they have a chance at a healthy future," he says.

On the other hand, the non-exercising control group's endothelial dysfunction worsened, fitness decreased, and the children gained weight--an average of 1.8 pounds per child--on track for an annual weight gain of at least 10 pounds.

According to Dengel, current projections show that when today's children reach age 44, 87-90 percent will be overweight. He hopes his research can lead to societal changes to promote health among all children, starting with improvements in the nutritional value of school lunches, and increased physical education and recess time.

"If we think about schools as just a place where intellectual learning happens, we will continue to add to the problem of childhood overweight and obesity," he says.