Welcome to 24 Hour Fitness. At our health and fitness centers, we believe in changing lives through fitness. Our state-of-the-art facility has just about every feature you could wish for in a gym membership. If you are looking for a fitness club in Arnold that offers a wide range of group exercise classes and personal training, then make 24 Hour Fitness your Arnold gym. Find out more about 24 Hour Fitness centers in Arnold, MO, join online, or get your free 7-day pass today.