Picture a ski racer hurling down a slalom course with arms out front, body tucked and skis scraping against icy snow. Did you picture gray or balding hair under the helmet . . . how about arthritic knees? Many older racers who love the thrill of running gates still compete in the New England Masters Racing Program. Vermont Public Radio's Nina (Ny'-nuh) Keck caught up with some of them at a recent race at Killington, Vermont.