One of the most intriguing things about our style of training, "CrossFit - Constantly Varied, High Intensity, Functional Movement," is that we consistently see performance improve in domains we are not necessarily targeting.
For example, when we train short duration high power output i.e. our conditioning WODs, we can still perform longer duration activities fairly well...like the bridge run (10k). We can also take a beginner / intermediate athlete and improve their deadlift over an 8 week time period by targeting strength of squats and presses. (caveat: once an athlete starts moving from intermediate to advanced specific training is required to see advancement).
*The statement above is highly general and intended to allow the discussion below to happen.*
One of the reasons we see this is part of the definition of CrossFIt: functional movement. These movements are also described with terms we use in the gym like core to extremity; multi-muscle; and sayings like "we don't use machines, you are the machine". We perform tasks that utilize the individual parts / muscles in concert to generate high power output. Training this way trains your entire system, your body as a whole.
Why are we talking Anit-Fragile?
This term came out of a book I got into called Antifragile. By our very nature we are what the author describes as anti-fragile. Our bodies thrive when put into an environment where disorder or other stressors challenge our systems. This is true to a point obviously. Everything has a threshold...the stress and disorder of getting hit by a bus certainly will not help you thrive. However, putting your body into situations (upside down on a wall) or under loads (max effort deadlifts) that it is not accustomed to will improve your level of fitness. When performed in an environment where the safe, performant positioning and proper recovery are prioritized, an ELETE level of fitness and health can be obtained.
This is exactly why the mantras we adopt as Iron Bridge CrossFitters are so important to getting the results you want out of your training. "Pushing through the suck", "working on what you are not good at", "puking is acceptable quitting is not", "iron forges man", etc. These all set the tone for the level of hardening we push for in order to remain Anit-Fragile.