[StefanMoroni]

Hi,

I’ve recently decided to experiment with a low-carb diet (no carbs throughout day then eating a normal, big dinner). I’ve also been steady state training, improving up to around 20 mi/week running near my aerobic threshold (145bpm).

I’m coming off of a rest week (maybe should have switched before rest week), but I’ve felt off all week, and most noticeably, my pace has slowed around 2 min per mile at that threshold heart rate. I’ve read about the “keto flu” and it seems like I’m experiencing a lot of the symptoms (stress, headache, carb cravings).

Curious whether or not you have seen this in the past, and if so, whether I should try and grind through the bad symptoms for some light at the end of the tunnel, or whether this type of diet isn’t compatible with long and slow training. Philosophically, they seem to align, but I feel like crap!

Thanks for all the info you have put out there, I’ve really seen an improvement in my running and in my ability to grind through long days in mountains.

– Stefan

Topic

[Anonymous]

Anonymous on August 30, 2020 at 8:28 am #44628

Stefan:

Those symptoms are consistent with what I have seen when folks are transitioning to a ketogenic diet. We’re not big on the keto diet here at UA. Not because it does not work. It will make you very fat adapted over time but it is very hard to maintain and if you fall off the diet then you have to go through this very unpleasant transition period again….and again….and again. It can also be awkward to to be that person who can’t eat certain thing when in a social setting. And it is not necessary to accomplish fat adaptation.

We advocate; in the many articles on this site and in the recent podcast I did with Rebecca, a more tempered approach. Reduced carb intake coupled with training in Z1-2 has proven in hundreds of athletes we’ve worked with to cause good fat adaptation without the severe side effect that you are experiencing.

This experiment you have been conducting seems to show that this is not working well for you. I would suggest a more moderate approach like we recommend. Do not make major shifts in diet or training. Be very gradual about introducing these things and you body will adapt but it if you hit with a big hammer it will rebel.

Scott