Sweat-suited and sneaker-footed, with pedometers clipped firmly at waists, they appear, sometimes before dawn, and slip quietly through the shopping-mall entrance with a wave to smiling guards. Early-bird bargain hunters? Well, no. These are not sales stalkers but a growing breed of fitness faddists, the mall walkers.
Walking is the preferred exercise of more and more Americans, especially the aging and ailing. "It's aerobic, it burns calories, and it's less intense than jogging," says Gary Yanker, editor of Walking World. "More people are regular walkers than runners, about 55 million compared with 34 million." Malls--conveniently located, climate controlled and security patrolled--have...