The 2016 Reebok CrossFit Games were a grueling five-day, 15-event test to find the fittest man and woman on Earth. 'Fittest on Earth: A Decade of Fitness' follows the dramatic story of the top athletes who qualified and competed and offers an inside look at what it takes to be among the world's elite athletes, both in training and on the competition floor. The CrossFit Games challenge competitors to perform intense physical tasks, but the hardest part is sometimes mental. Athletes often learn the details of the events only minutes before they begin, and everyone handles the pressure differently. Which of these fierce competitors will rise to the top and earn the title of Fittest on Earth?