CrossFit - the program on the website and the methods taught at their "certs" - is Exercise, not Training. Exercise is physical activity for its own sake, a workout done for the effect it produces today, during the workout or right after you're through. Training is physical activity done with a longer-term goal in mind, the constituent workouts of which are specifically designed to produce that goal.
Exercise is fun today. Well, it may not be fun, but you've convinced yourself to do it today because you perceive that the effect you produce today is of benefit to you today. You "smashed" or "crushed" or "smoked" that workout... today. Same as the kids in front of the dumbbell rack at the gym catching an arm pump, the workout was about how it made you feel, good or bad, today.
In contrast, Training is about the process you undertake to generate a specific result later, maybe much later, the workouts of which are merely the constituents of the process. Training may even involve a light day that you perceive to be a waste of time if you only consider today.
CrossFit is a random exposure to a variety of different movements at different intensities, most of which are done for time, i.e. as many reps as possible in a stipulated time period or a stipulated number of reps done as fast as possible. As such, it is Exercise, not Training, since it is random, and Training requires that we plan what we are going to do to get ready for a specific task.
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For most people, exercise is perfectly adequate - it's certainly better than sitting on your ass. For people who perceive themselves as merely housewives, salesmen, or corporate execs, and for most personal training clients and pretty much everybody who can afford a CrossFit membership, exercise is fine. CrossFit sells itself by advertising the random part: random is not boring, and not-boring gets people to come back. Coming back while doing the diet at the same time gets you abs. CrossFit is largely about abs.
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But this active retainment of members actually using the gym creates a unique problem for CrossFit facilities that no one else in the standard fitness industry has to face: the post-novice trainee.
As you are obviously aware (since you have memorized my books), a novice trainee is one for whom recovery from each workout is possible within a very short timeframe - 48 hours or so. This is because untrained people are unadapted people, and for unadapted people anything that's harder than what they've been doing causes an adaptation.
This is why CrossFit works so well for the vast majority of the people that start it: for the first time, an exercise program causes them to experience rapid improvement... at first. Then the problem with CrossFit becomes obvious.
CrossFit is not Training. It is Exercise. And exercise -even poorly-programmed random flailing-around in the floor for time- causes progress to occur,for a while. For the novice, CrossFit Exercise mimics the effects of Training, because it's hard and because stress causes adaptation. Then, progress slows, since the Laws of Physiology cannot be ignored. The more you adapt to physical stress, the stronger and fitter you become. And the stronger and fitter you become, the more difficult it is to get more strong and more fit, because the easy part of the process has already occurred.
This is called the Principle of Diminishing Returns, and is evident throughout nature and your own experiences, if you have paid attention. Once the low-hanging fruit have been picked, you have to get a ladder, and then you might need a helicopter - and each increase in complexity yields less fruit, dammit.
And this is precisely where CrossFit: The Methodology falls apart. Once a person has adapted beyond the ability of random stress applied frequently under time constraints to cause further improvement, progress stalls. And increasing the intensity of the random stress doesn't work either - that just gets you hurt because you haven't gotten stronger, and your heart and lungs can only work at about 200 BPM and about 50 RPM.
Further progress must be based on an analysis of the adaptation you want to create, and a program of Training for the purpose of causing that adaptation to occur must be correctly designed and followed. Beyond a certain point, random physical stress fails to continue to elicit a favorable adaptation.
CrossFit appeals to many people because it claims to be about doing everything well and nothing perfectly. Humans cannot excel at everything, as evidenced by the individual performances within the Decathlon as compared to the specialists' performances in those events. But at some point, even people who don't want to excel at anything in particular realize they aren't really improving at anything in general. People motivated to get this far are also motivated to continue improving, and even if you want to be merely good at everything, there must be a way to continue to improve this general competence. "Mainsite CrossFit" cannot drive this improvement beyond a certain point.
This is precisely why the advanced athletes who win and place at the CrossFit Games do not use CrossFit website programming to achieve advanced levels of the strength and conditioning necessary to perform at that level. None of them. This is widely known and freely admitted by everyone not involved with the company. All athletes at advanced levels must Train intelligently to advance, and CrossFit: The Methodology doesn't do the job.