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 Boulder that offers a wide range of group exercise classes and personal training, then make 24 Hour Fitness your Boulder gym. Find out more about 24 Hour Fitness centers in Boulder, CO, join online, or get your free 7-day pass today.