Down the main artery of the mall he strides - past Macy's and Penney's, past consumer electronics stores and clothing boutiques, around the food court and the locked-up carousel, down every corridor to every entranceway and back. But [Harold Shipman], 76, is neither a security guard nor a member of one of the maintenance crews buffing and polishing the floors at this early hour. He's a walker - a mall walker, to be precise. Seven mornings a week, he's here, navigating the interior, 1.1-mile perimeter of the mall three times. Same stores, same tile floor, same [Mike] and Carol, same three miles. "I don't get bored," says Shipman, a widower who lives in Selden. "This is what we do. And it's good for you."

She speaks from experience. In an effort to lose weight, [Sara Donovan], now 53, had tried everything - diets, health club aerobics classes, jogging around her neighborhood in St. Paul. She couldn't seem to stick with anything until her physician recommended walking. She lost 15 pounds, mostly by walking on an indoor track, and became a competitive race walker. When the world's biggest mall, the four- story Mall of America, opened in nearby Bloomington, she was invited to come in and lead a walking program. Founded in November 1992, the MallStars are now the country's largest mall walking group: 3,000 strong, sometimes up to 800 a day, walking around the vast mall.

This region, of course, stands second to no part of the country in its love of shopping malls. So it should come as no surprise that a vibrant mall walking community exists here in Nassau, Suffolk and Queens. The oldest and (with 1,500 members) largest local mall- walking group is the one at Smith Haven. It was started in August 1990, by two volunteers with the Suffolk County chapter of the American Heart Association, Ron Barber of Stony Brook and Gene Pritz of St. James.