CrossFit is a precise combination of exercise and nutrition that has been proven to increase fitness and health for people of all ages and abilities. CrossFit is founded on the first scientifically rigorous definition of fitness: The program produces observable results that can be measured and replicated. You can do CrossFit with a credentialed CrossFit trainer or in a supportive, motivating community like Driving Force Crossfit, or you can do CrossFit in your garage or home gym.