Every health marker you can think of can be measured by a continuum labeled “Sickness-Wellness-Fitness”.
What is a “Continuum”?
Think of it like a movie. If you stop the movie you see a snapshot of the movie at that particular moment in time. We can take a snapshot (a value) of a health marker and determine if that value is more on the Sickness end, Fitness end or somewhere in between on that health marker’s continuum.
For example, a blood pressure of 160/95 is pathological (Sickness), 120/70 is normal or healthy (Wellness), and 105/55 is consistent with an athlete’s blood pressure (Fitness); a body fat of 40 percent is pathological (Sickness), 20 percent is normal or healthy (Wellness), and 10 percent is fit (Fitness). We observe a similar ordering for bone density, triglycerides, muscle mass, flexibility, high-density lipoprotein (HDL) or “good cholesterol,” resting heart rate, and dozens of other common measures of health (Table 2). These health marker values (snapshots) will show us how healthy we are at that particular moment in time.
Many authorities (e.g., Mel Siff, the NSCA) make a clear distinction between health and fitness. Frequently, they cite studies that suggest that the fit may not be health protected. CrossFit feels that fitness, done right, provides a great margin of protection against the ravages of time and disease. Fitness is and should be “super-wellness.” Sickness, wellness, and fitness are measures of the same entity. A fitness regimen that does not support health is not CrossFit.
The motivation for the four CrossFit models is simply to ensure the broadest and most general fitness possible. Our first model evaluates our efforts against a full range of general physical adaptations; in the second the focus is on breadth and depth of performance; with the third the measure is time, power and consequently energy systems; and the fourth is on health markers. It should be fairly clear that the fitness that CrossFit advocates and develops is deliberately broad, general, and inclusive.
Our specialty is not specializing. Combat, survival, many sports and life reward this kind of fitness and, on average, punish the specialist.