The first 24 Hour Fitness Express will open sometime this winter in Fair Oaks … adding to the 10 much larger gyms it already has in the Sacramento region. This new company format is closer to the circuit-training locations made popular by Curves and Slender Lady. With less space, less gear, and less overhead, it’s a concept that can work in neighborhoods lacking the population to support a full-service workout center. It’s also appealing to two groups: those intimidated by full-blown workout centers, and people with only 30 minutes to invest in staying fit.