What is Fitness?

Click here to get the original article from the CrossFit Journal.

Can you define fitness? Some people have tried. Dictionaries have tried but they always come up short.

fitness |ˈfitnis|

the condition of being physically fit and healthy: disease and lack of fitness are closely related | [ as modifier ] : a fitness test.

  • the quality of being suitable to fulfill a particular role or task: he had a year in which to establish his fitness for the office.
  • Biology an organism's ability to survive and reproduce in a particular environment: if sharp teeth increase fitness, then genes causing teeth to be sharp will increase in frequency.

Crossfit’s Redefinition of Fitness

Coach Greg Glassman (CrossFit’s founder) felt this definition was circular thinking and in no way helped a person clearly measure if they were fitter from one day to the next. Rather than simply be frustrated he decided to redefine fitness. He did so in a way that gave us a granular metric for measuring fitness (exactly how much fitter one person is than another). In the process of redefining fitness, he came up with three models that we can use to grasp the expansive possibilities of fitness.

Three Models of Fitness

These three models are interesting on their own, but we must use all three together in order to understand the scope of CrossFit’s definition of fitness.

1. The Ten General Physical Skills of Fitness

  • Cardiovascular/respiratory endurance – The ability of body systems to gather, process, and deliver oxygen.
  • Stamina – The ability of body systems to process, deliver, store, and utilize energy.
  • Strength – The ability of a muscular unit, or combination of muscular units, to apply force.
  • Flexibility – the ability to maximize the range of motion at a given joint.
  • Power – The ability of a muscular unit, or combination of muscular units, to apply maximum force in minimum time.
  • Speed – The ability to minimize the time cycle of a repeated movement.
  • Coordination – The ability to combine several distinct movement patterns into a singular distinct movement.
  • Agility – The ability to minimize transition time from one movement pattern to another.
  • Balance – The ability to control the placement of the bodies center of gravity in relation to its support base.
  • Accuracy – The ability to control movement in a given direction or at a given intensity.

How would you rate your competency on these 10 physical skills? Is any one obviously a weakness?

2. The Hopper

There are an infinite number of physical activities that a person can perform; from hiking to fighting in a war and everything in between. Let’s pretend we placed that infinite list into a bingo hopper and selected activities one by one at random. The ability a person has to perform each random task would be a measure of their fitness. Therefore, a fit person could handle any activity drawn out of this hopper with a level of competency. While an unfit person would struggle.

If you participated in a hopper test what would you be afraid would be selected? Is your training improving your ability to perform that activity well?

3. The Energy Pathways

We (generally) operate on three energy systems: Phosphagen, Glycolytic (Anerobic), and Oxidative (Aerobic). This third standard of fitness holds that a fit person has a level of proficiency in all three of these energy pathways.

  • The Phosphagen system – This system is used only for short efforts of up to 10 seconds. This is the primary system behind very short, powerful movements spiking a volleyball, a 100m sprint or powerlifting.
  • Glycolytic System – This predominantly supplies energy for exercises lasting less than 2 minutes. An example of the glycolytic system at work would be a 400m sprint.
  • Oxidative System - This is the long duration energy system. After about 5 minutes of exercise this system starts to takes over. In a 1 km run, this system is already providing approximately half the energy; in a marathon run it provides 98% or more.

Are you working in all three energy pathways? Do you avoid heavy lifting days or sprints? What about going long every once in a while?

It is the combination of these three models that gives us the fullest picture of what fitness is. So if your idea of fitness is a triathlete you can now see that they probably neglect many of the 10 physical skills, if it’s not running, cycling or swimming they’d probably struggle with a hopper test, and they spend most of if not all of their time training in the oxidative pathway.

This definition of fitness sets a high standard. In the next post we’ll take a look at how CrossFit delivers a proficiency in all three models.

Now go move better.