This comes up in virtually every “Science Lab” seminar that we offer free when you purchase things that support our site (it’s mostly stuff you would buy anyway). Click the link and it will give you more details. I am really hoping this post clears things up.
That answer is a definite no (in my opinion). In the first video Kiefer talks about how you can shorten the prep phase of CBL by 3 days by doing HIIT training. Crossfit is HIIT training for the most part. So if you Crossfit you are already, mostly, addressing this concern. Namely the idea of emptying out your glycogen stores. The other part of this that isn’t insignificant is that you probably already have been low carbing if you follow Paleo. Much of what I am talking about is about improving metabolic function. CNS is most for sedentary people. These two videos explain that and great deal so it should be relatively enlightening to everyone that if he is asking the question “should you be working out on CNS” then you probably shouldn’t be Crossfitting on CNS.
There is another part to this question however because inevitably I always get “but I CNS and do Crossfit and I love it”. No offense to any of these people but you can’t perform at a high level keeping your carbs under 30g a day like Kiefer is suggesting. Is there a compromise? Yes, that is what CBL is about, it is an intra day cycling protocol, so that is one strategy. The other strategy is to use “fat” days as “control” days. Kiefer covers the concepts of CNS in CBL so buying both books is redundant and CNS is a pretty simply idea. Basically you cycle your “fats/control” days around your rest days. So basically you carb up, you WOD with a rest day coming the following day and you keep your carbs lowish. Not zero or even under 30g, there is no magic to this by the way. You should still keep your calories relatively high but your control days allows your body to process some of the excess carbohydrate you would rather not have contribute to fat storage.
Carb Nite: Should you Workout?