You can’t just do work that is painful just because it hurts and expect to get better.
The central claim is that you can get the same endurance benefits (or better) from doing high intensity work and limit any slower to moderate paced running.
They first created their own new performance metric on which you’re judged.
Because being good at all the other methods of establishing performance isn’t good enough, so now you’re judged based on some criteria that crossfit develops. Additionally, they really go after this hard work/pain = improvement and results idea. But if you’ve been in the coaching business long enough you know that hard stupid work doesn’t get you anywhere.
Think back to your HS days when you spent a summer building a base of almost just mileage and then you hit the season and your coach starts throwing interval training into the mix. This is essentially what happens in these research studies.
They take recreational runners who just do easy/base stuff and then throw 6 weeks of training hard on them and they improve.
A researcher named Tabata did a series of studies on untrained and then moderately trained individuals in which he gave them a workout that consisted of 20sec hard/10sec rest for 4minutes.
When this program was researched, they noted that VO2max increased by a large amount and that certain aerobic enzymes also increased.
In that different intensities and volumes will increase aerobic or anaerobic enzymes in each type of fibers along the spectrum.
What that means is that although high and low intensity might both hit similar aerobic enzymes, they do so in different ways and in different fiber types.
Ask any coach and they’ll say this is just a simple old school peaking/training program.
In fact, it might resemble your typical HS application of Lydiard training.
In CF this refers to a variety of high strength circuits and in CFE it combines this with high intensity intervals like the famous Tabata “sprints” (sets of 20sec hard/10sec easy). It’s simply mix short intensity work with slightly longer high intensity work and that’s all you get. We’ll go over this straw man tactic a bit later, but they try and cultivate this idea that just because it’s different and new means its got to be better.