London ? Attention all shoppers: taking the stairs protects your heart.

That’s the message researchers tried at a suburban shopping mall by putting up colorful signs along the steps of a staircase, and it worked. Over six weeks, use of the stairway next to an escalator more than doubled.

Normally, about 4 percent of people at the mall take the stairs but after adding the signs, that went up to nearly 10 percent. The findings were recently published in the American Journal of Health Promotion.

“A certain segment of the population clearly responds to these messages,” said Frank Eves, one of the study’s authors and a senior lecturer in applied psychology at the University of Birmingham.

Eves and colleagues counted the number of people at a mall who climbed the 15 steps before the signs went up and after they were posted. They counted more than 82,000 shoppers at the mall in Coventry, in western England.

“If we can persuade more people to take the stairs, then we might really have something in the war against obesity,” he said.

With fewer daily opportunities for physical activity in modern society, public health officials are increasingly focusing on stairs at schools, workplaces and even the mall. Past studies have also shown that the decision to take stairs can be manipulated relatively easily with a few signs.

Still, experts think that to change behavior long term, the signs need to be seen regularly. At the U.S. Centers for Disease Control and Prevention in Atlanta, physical activity experts tested that in a 2002 campaign to boost internal stair use.

By tacking up signs promoting stair use and transforming their ugly, concrete stairs into a carpeted, bright stairwell with artwork and piped-in music, CDC officials have bumped up stair use by nearly 20 percent.

Experts emphasize that just climbing one flight of stairs at a shopping mall is not going to improve your health. But they hope the signs may inspire some people to regularly forgo escalators in the future.