Ultimate Ninjas in O'Fallon, Missouri is a Ninja gym that offers a variety of fitness programs and activities for kids and adults. They provide kids fitness classes that focus on building self-confidence, agility, and overcoming obstacles. The gym also offers open play sessions for families to enjoy together, as well as birthday party packages that include access to the indoor obstacle courses. For adults, Ultimate Ninjas offers fitness classes and competitions. The gym is staffed by American Ninja Warriors who train to conquer the obstacles seen on the NBC hit show, American Ninja Warrior. Ultimate Ninjas has received positive reviews for its engaging and fun environment for kids to learn balance, coordination, and perseverance.