Originally Posted by Scoobey
So my Q for discussion is: does anyone know of any research on how well long-time low-carbers switch metabolic modes during high activity? Can we temporarily add substantial carbs without sacrificing our wonderful efficiency at buring fats for fuel a few hours later?
I can only tell you how my body reacts to that scenario.
When I first started my keto diet over a year ago it took me weeks to really feel the benefits of a low carb diet. I had an Atkins flu that lasted for 3 days, it was horrible... I honestly did not have enough energy to walk, it was brutal. I spent that time in bed sleeping as best I could.
About 3 months in to my diet I took a 1 week break for a local Greek Food Festival, so many carbs. After this it took me about 4-5 days to feel at my peak strength again and my "atkins flu" was only one afternoon that I had to leave work early because I was tired (still significant mind you, but much, much less).
Since those times I have taken some breaks from the diet and then hop back on. I took a month off thanksgiving/christmas, then went back on for a few months (I don't recall any Atkins flu). Then I ended up eating carbs for a few months in a row.
I went back on my keto diet about 2 weeks ago. I had no problems transitioning to work (I'm a stone mason so I am asking as much from my body as you are from yours). There wasn't a day, or even a few hours where I felt as though my body was deprived of energy. Thursday (a little over a week in) I shoveled 32 tons of gravel, something I would only have the energy for if I was in full-blown ketosis (which is supposed to take 4-6 weeks).
I imagine that everyone's body's would likely have a different reaction... But mine seems to (after transitioning from carbs to keto several times now) have absolutely no problems at all.
Now, your question seemed to be a little more directed towards say doing something physically intensive that would require say, 2k calories; eating 2k carb calories and going back to fat. I have never tried this as I have much more energy available (not just sustained, but also that) in ketosis.
What about taking Pemmican for your search and rescue stuff?