Olivia Thomas, Ph.D., is conducting a pilot study to develop exercise programs for overweight African-American youths that can change their body composition and enable them to live healthier lives.

Olivia Thomas is the principal investigator of the ‘Fit Club at the Y’ study, which aims to develop exercise programs for overweight African-American youths that can change their body composition.

“Fit Club at the Y” is a 12-week study for children ages 10-12 funded by the Charles Barkley Health Disparities Research Award.

“There have been several large behavior-intervention trials designed to reduce obesity in children through increased physical activity,” says Thomas, assistant professor in Epidemiology. “Even though these trials were very well designed, the impact of these studies on body composition has been limited.”

There are recommendations about how much exercise all children should have each day, but the type and amount of exercise needed for an already obese child has not been established, she says.

“We’ve really put the cart before the horse in terms of establishing how much exercise overweight children need to actually change their body composition,” Thomas says.

“We thought we needed to go back to the drawing board and start with an efficacy trial that’s closely monitored and controlled. We want to see the impact of an exercise program when we’re controlling the dose and measuring total physical activity.”

Overweight children at risk
Until now, no one has established a dose-response relationship between physical activity and obesity in children. U.S. Department of Agriculture dietary guidelines suggest that children should get at least an hour of moderately intensive physical activity every day, but there are no data available showing that this dose of exercise is effective for managing body weight in children.

According to the National Center for Health Statistics in 2006, about 34 percent of children ages 6-19 are overweight; about half of those are considered obese, up from 11 percent in 1994.

Rates are highest among African-American adolescents. Statistics from 2002 show that almost 24 percent of black girls and boys ages 12-19 were obese.

Research shows that overweight children are at a higher risk for health problems that plague overweight adults, including hypertension, breathing disorders, sleep problems and bone-and-joint complications. They also are at greater risk for developing heart disease and some forms of cancer.

“Fit Club at the Y” will randomize 15 participants into three groups. One group will be the control; the two exercise groups will participate in either 30 minutes or 90 minutes of supervised, moderate intensity activity.

Those randomized to one of the two exercise groups will be carefully monitored five days a week for 12 weeks at the Western Area Family Branch of the YMCA in Birmingham.

The study is for children who are overweight, but otherwise healthy. They should not have health issues related to diabetes, hypertension or asthma or be taking medications that would interfere with their body composition.

Children participating in the study also should not have participated in an exercise or dietary program for weight loss.

Prescription for exercise
Thomas and Jana Wallace, project coordinator, will create an exercise prescription for each child enrolled in the study.

Participants will spend one night in the General Clinical Research Center so their resting energy expenditure can be measured. They also will have their body composition measured, undergo a fitness test to determine their target heart rate range and give blood samples to test their lipid and insulin levels.

Children will be wearing heart-rate monitors that show their activity levels during the supervised exercise sessions. They also will have a variety of exercise options at their disposal.

“We’re allowing them to participate in all of the activities at the YMCA, including basketball, walking, swimming, soccer, active video games and many other activities,” Thomas says.

“The goal — regardless of the exercise they are doing — is to maintain their target heart rate for moderate intensity physical activity. We just want to be sure they have plenty of options for their exercise to be fun because they are coming five days a week, which is quite a bit.”

Efforts are under way to expand this study in the future. Call Thomas at 975-7662 or Wallace at 975-8383 for more information on the study or inquire about enrolling a child. You also can e-mail Wallace at wallacej@uab.edu.