#8 Periodization matters:
It seems simple enough that people would know that how you plan and periodize training matters. Training isn’t a random collection of hard exercises or workouts. There has to be some sort of logical sequence and progression. If there’s not, then you can expect to get exactly what you trained for, random results.
The bottom line is that so called high intensity interval training (HIIT) which is the new fad word with strength coaches is good. But for endurance performance it’s even better when it is supported! You have to support it with something. Endurance work of various kinds and even pure speed work (with lots of recovery) serves as support for the intense stuff.
#9 Interaction matters:
Endurance and strength gains fight each other a bit for adaptation. While I don’t want to get bogged down in the details, if we look at the signaling pathway for some endurance adaptations and then muscle hypertrophy which are two goals of CF and CFE, we can see that they interact and in fact impair each other in some cases. For example, doing endurance work right after strength can impair hypertrophy because the mTOR pathway(which signals hypertrophy among other things) is basically switched off with endurance work. This isn’t meant to show that they are mutually exclusive, but instead to show that when you do things matters. Sometimes a whole heck of a lot! Thus why you have to think about and plan things, not just do random hard workouts.
This goes for not only sequencing of endurance and strength work, but also in regards to sequencing different strength workouts. You have to know what pre-fatiguing muscles does to the subsequent training effect. And you have to know what the effect is on the Central Nervous System. Crossfit doesn’t think about this at all. They don’t care.
My number one pet peeve. There is no individualization. Workout of the day. That’s the norm. Beyond that, everyone does the same crap for the most part. I could go on for days on the importance of individualization, and CF and CFE fail miserably.
What does this all mean?
What happens in the long term?
Again, I’m going to ask a rhetorical question, for you HS coaches out there what happens if you mess up the balance and do too much intense interval training after that base phase? The answer is the kids fried. You see it all the time in High School. A kid hits the interval training hard, runs some amazing early season times and then fizzles out and is fried by the end of the year. That’s what happens training wise. If you want lactate proof, this is what happens aerobically if you mess things up. You shift the balance to working anaerobically too much (Test #3) and you produce more lactate at each pace, and you are done!
The reason is that there is an interplay between easy to moderate running and intense running or even strength training. If you work too much on the intensity or strength side you shift things towards that way. In practical terms your lactate produced at each speed might go up or you might decrease aerobic ability a little bit. Same goes if you do too much volume with not enough speed support. You’re speed side would be neglected so that would go down. It depends on what you are training for but achieving some sort of balance is key.
Additionally, if we look at very long term implications for performance we know that the foundational aerobic mileage does a few things. First in long term studies on Cross Country skiers, the high volume of training created a fundamental shift in fiber type towards those which improved their performance. So we got a ST fiber type shift for guys who needed lots of ST. Secondly, the high volume of training leads to long term increases in efficiency. Yes, high intensity work or even lifting can do this too but again it’s through different mechanisms. Lifting for example can increase efficiency via modulating stiffness of the system. Or essentially creating a stiffer spring. High Volume training on the other hand works via increase the efficiency of both motor program patterns (because of the repeated nature) and at the muscular level in terms of oxygen utilization and waste product removal. Again, two different ways to hit the same functional adaptation (improved efficiency), so why would we just want to work on one of them.
So we have research showing that in very elite runners, long term high volume training is needed to make functional changes. We have practical experience in that throughout history we’ve shifted towards the volumes we do now and that practically every single good runner does a solid amount of mileage (with good intensity mixed in) and we have the theory of why mileage should work.
If we simply put crossfit endurance through the same kind of review we have:
Research- short term studies on high intensity training shows improved VO2max and in some cases performance, but we have looked at why those don’t apply neatly already. No research on crossfit endurance in particular
Theory- It goes against all known scientific theory for how endurance performance should be improved and how it actually happens.
Practice- No good runners do it. We know from history what happens and what kind of performance you get even if you do a lot of high intensity work with very little volume.
And lastly, it doesn’t help that they subscribe to every fad from diet to pose method of running that there is.
Finally, if you want a very interesting research approach to the high volume/intensity paradigm read Stephen Seiller’s nice summary here:
And finally, I’d like to point out that finishing and racing are different. I’ve heard far too many times that so and so did crossfit and finished a marathon so it must work. No offense and sorry to sound elitist, but if I took off 6 months and did nothing I could still finish a marathon. It doesn’t mean my program of doing nothing worked.
What does this all mean?
While this was a lengthy rant, it only touches the surface of the Crossfit or Crossfit Endurance phenomenon. My point wasn’t to critique everything they did (that might be later) but to teach you why some of their claims they make, even research based claims, might be wrong.