CrossFit’s second model for fitness is the HOPPER.
A CrossFit HOPPER is a spinning barrel that has an infinite number of physical challenges written down on pieces of paper or on lottery-style balls. The HOPPER spins and a random piece of paper or ball falls out with a physical challenge to be performed. The piece of paper could read anything from a 5k run or 21-15-9 Thruster and Pull-ups or 100 burpees for time or 1 mile 200# sandbag carry.
Think of any physical challenge, it is in HOPPER, as well as all challenges you did not think of.
CrossFit prepares you for this “Unknown and Unknowable” concept. The “Unknown” challenges are all the challenges you know but do not know which one is going to drop out the HOPPER. The “Unknowable” challenges are all the challenges you did not think about that can drop out of the HOPPER. People never know what physical challenges they may be faced with at any particular point in time in their life. We want to be ready for anything, that’s why we do CrossFit.
Going back to CrossFit’s first model for FITNESS: 10 physical skills.
The better you are at those 10 skills the more prepared you will be for the “Unknown and Unknowable”. CrossFit therefore suggests that our fitness can be measured by the capacity to perform well at these random physical challenges in relation to other individuals.
The implication here is that FITNESS requires an ability to perform well at all tasks, even unfamiliar tasks and tasks combined in infinitely varying combinations. This encourages the individual to not focus on regimented exercise routines where every rep, set and exercise progression is calculated.
Nature frequently provides largely unforeseeable challenges; train for that by striving to keep the training stimulus broad and constantly varied ie: CrossFit.