LOUISVILLE — This city’s Broadway displays its own array of neon signs — two dozen fast-food restaurants, as diverse as McDonald’s and the local Indi’s — beckoning along a 2.8-mile corridor bookended by low-income neighborhoods on the front lines of a multimillion-dollar battle against obesity.

The street symbolizes one of many hurdles facing officials here working to put a severely overweight population on a diet. After all, Kentucky is where Colonel Harland Sanders first made his famous fried chicken and a hotel invented the Hot Brown, a turkey-bacon sandwich drowning in Mornay sauce.

In many ways, Louisville’s experience in fighting obesity is little different from that of a dieter stepping on and off a scale. Successes on one front are countered by setbacks on another, and signs that the needle has moved overall are slight and mostly anecdotal.

More than six in 10 people in metro Louisville are still considered seriously overweight, in a state that ranks seventh in the nation for obesity. The rates continued to rise through 2008, while the percentage of the population reporting any physical activity outside of work fell despite public campaigns advocating more walking and biking.