WASHINGTON -- Surgeon General Richard Carmona and soccer star Mia Hamm have a message for America's kids -- get off the couch.

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They have helped kick off a multi-year, $4 million partnership designed to increase physical activity and prevent childhood obesity.

The program, called "Get Kids in Action," is backed by the University of North Carolina at Chapel Hill and Gatorade.

"We are seeing a generation of kids who are growing up in front of the TV and computer and away from the playground and ball fields," Carmona said. "Childhood obesity has more than tripled over the past 40 years, and this epidemic will lead to an obese and therefore unhealthy adult population unless we do something now."

Carmona said kids should get at least 60 minutes of physical activity a day.

Hamm, who plays for the Washington Freedom and the U.S. Women's National soccer team, said kids who are active and healthy will feel better and have more confidence and higher self-esteem.

"I am as passionate about encouraging kids to get active as I am about winning on the soccer field," said Hamm. "There is no more important message that athletes can send to kids today than to get up, get active and have fun. Being active as a kid sets an important precedent for being an active and healthy adult."

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