MORGANTOWN — After weeks of bopping along to the video game Dance Dance Revolution, Ryan Walker is trimmer and stronger — and for the first time the 12-year-old feels comfortable in his own skin.

“Before, he didn’t want to play with kids, go to school dances or any of those functions — and now he wants to do things,” says his mother, Tammy Walker.

Ryan’s transformation occurred over the 24 weeks he participated in a West Virginia University study that hoped to determine if the exergame could be used to combat the nation’s child obesity problem.

The study, funded in part by West Virginia’s health insurance program for public employees, took 35 overweight children between the ages of 7 and 12 and asked them to gradually increase the amount of time they played the game. Each child was medically considered overweight according to his body-mass index, a measurement of body fat through a height and weight ratio.

What researchers found was that participants who regularly played and continued to eat fatty foods were able to slow down — but not stop — their weight gain. Researchers are calling it a “stall in weight gain.”

Children who relied on the game as their sole source of exercise gained 2 pounds during the study. Those who did not play the game gained an average of 5.3 pounds.

“We didn’t even attempt to change their diet, which is another reason that we didn’t see significant weight loss,” said WVU researcher Emily Murphy.

Instead researchers found that in addition to better artery expansion, some participants developed physical self-esteem.

The game’s addictive nature, and capacity to lead to greater physical activity, earns it a comparison to drugs, with WVU researcher Linda Carson dubbing it a “gateway physical activity.”

“The first night I did it about 30 times in a row, I didn’t want to stop,” Ryan said.

The game is played on a dance pad with eight arrows pointing forward, backward, left, right and diagonally. Players press the panels with their feet in response to arrows displayed on the video screen that are synchronized to the beat of a chosen song.

Success is measured by the player’s ability to time and position his or her steps.

The study directed participants to work their way up to playing 25 songs — equal to about an hour of playtime a day — and researchers called weekly to check on progress.

But simply introducing exercise into lifestyles that include french fries as dietary staples won’t correct obesity, researchers said. That’s unfortunate news for West Virginia, where nearly 21 percent of state residents under 18 are considered overweight, according to Trust for America’s Health.

The state’s rural nature, which hampers the development of exercise-oriented infrastructure, is partly blamed for the problems with obesity, state nutrition officials say. Poverty also plays a role as it affects nearly 1 in 4 West Virginia children.

Even staying after school to participate in athletics or extracurricular activities is a challenge because for many students a bus ride is the only way to and from school. Because of declining populations, many boards of education have consolidated schools, forcing students to catch long bus rides back home to isolated rural homes.

“In many of our rural areas there just isn’t a way to make a safe route for children to walk to school along roads that coal trucks and other fast traffic travel on,” said Melanie Purkey, executive director of the state’s Office of Healthy Schools.

Those are some of the reasons why the state has integrated Dance Dance Revolution into West Virginia’s 160 middle schools and is encouraging school administrators to make the game available to students during free periods before and after school, Purkey said.

Hawaii, California, Missouri, Florida, Tennessee and Mississippi also use the game in schools on a smaller scale, according to Clara Gilbert, a spokeswoman for Konami, the maker of the game.

Though Dance Dance Revolution has a workout mode built in, Gilbert said West Virginia’s use of the game “was a surprise because they wanted to put it in all public schools as a sport, for physical education. We never thought it would be used in a state in this magnitude.”

Use of the popular Japanese video game started in 2005 as a pilot project in 20 West Virginia public schools. Though Konami did not fund the study at WVU, it donated nearly $100,000 to bring the game to middle schools across the state.

Gov. Joe Manchin has called on the Legislature to provide $350,000 in next year’s budget for games for a health project in state schools.

Some parents may wonder if dancing to a video game is as good as running laps.

A Mayo Clinic study found that kids using Dance Dance Revolution for 15 minutes burn more calories than walking on a treadmill for the same period of time. In a University of Auckland study published last August, researchers found that 21 children who used physically active video games produced as much physical activity as walking, skipping and jogging.

“If we could get the kids to skip rope, that would be just as good. But you can’t get them to skip rope,” Carson said.

In many ways, Ryan represents the best case scenario for game users.

He’s gained 10 pounds since he began playing Dance Dance Revolution for the WVU study — but he’s also grown a foot taller, and is more fit and trim than ever before.

The more he played, the less he needed his inhaler, and the better he became at other sports, such as basketball.

And the more Ryan’s body changed from the exercise, the more he took an interest in improving his health. He still enjoys the occasional piece of cheesecake, but for meals he favors salads and low-fat sandwiches from Subway.

His mother says the most exciting changes in Ryan are the intangible ones.

He carries himself and talks to people with pride. Friends now come over after school to play basketball, filling a void where there was nothing but sedentary solitude before. And he now wants to attend school dances.

“Once you start playing you don’t realize you’re getting a workout because you’re having more fun than you’re working on it,” Ryan said. “That’s how it works.”