Thursday, December 28, 2017

HIIT works for everyone...until it doesn't

30 seconds of google image search for HIIT finds lots of nonsense - especially this time of year!
HIIT - high intensity interval training - aka Metcon - is an amazing tool. I would not be surprised to hear that you've done HIIT before (you're reading this blog, so the self-selection bias is pretty high here). I'd even bet you had great results with HIIT.  It is amazing at turning around body composition, kick starting fat loss, it makes you feel great, it even makes you stronger and better able to live the Boulder lifestyle.

It works so well that it's very easy to get into a more is better mentality. I spent many years doing a high frequency of HIIT training, and I was in the best shape of my life...until I wasn't.

There are many things that aren't sustainable about a steady regimen of HIIT, and here's an important one that I just learned about this week: you can damage your biochemistry.

If you're a long time reader of this blog, you know I care about staying out of that moderately intensity (fat burning) zone. For training, you need a LONG time in your aerobic (very low) zone (we've been calling that the antiglycolytic training) with some short bursts into the alactic (very high) zone.  What we don't do is spend much, if any, time in the glycolytic zone, and there's a very important reason for that.

Most of the sexy metcons out there are based on spending your time using the glycolytic pathway. CrossFit is centered around it. There are times where you need to be able to go into that pathway - but that's for performance, not for training. If you're a professional athlete, or a first responder, or a special operator, or really anybody whose job depends on your physical performance, you need to be able to use the glycolytic pathway to get your job done (or to be able to run from a lion and survive) - but you rarely need to train it.

When you spend time in that glycolitc pathway the major byproduct of combustion is acid. When you do a 7 minute metcon every single day (or worse, an hour of a series of metcons) you are bathing your mitochondria in acid. You are destroying the energy producing parts of your cells. You are breaking yourself.

That's why at some point HIIT will stop working. All of the benefits you got from HIIT will stop and reverse. You won't be able to maintain your body composition, your fat loss, your energy, or your strength. You will no longer have the biochemistry to produce energy.

Keep your intensity low, don't get lured into feeling the burn (guess what that burn is). Lift heavy, swing kettlebells for your power production, and rest.


row 500 / run 400
crawling lunge
10 KB swings or snatches
double KB overhead lunge
10 TGUs or windmills
10 goblet squats
5 pull-ups or push-ups or dips


squat 8-8-3x8


2 pull-ups + 2 dips between strength sets

Group Workout

6 rounds
5 1-arm kettlebell swing 
5 kettlebell back squat 
*Switch arms each round


4 rounds, as quickly as possible:
8 3/1000 hold bodyweight row
12 kettlebell halo + extension
6 pull up scaled to full ability 


2 minute bar hang


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