Ok so I am on my 4th day of my 30 days fast ((I have previously done few 10s and one 15s.) I am wondering what’s the upper limit to a slow paced cardio while I am feeling super energetic and sharp? My doubt is when glycogen stores are exhausted body switches to ketones. And when the body has a lot of fat in it is there an upper limit to the amount of ketones it can produce in a day? So let’s say as soon as a fat guy gets into ketosis, he can literally walk the earth fasting with just water and electrolytes on him and by the time he has reached his destination he is lean! Is this even possible?
PS: I am taking all the right amount of electrolytes - it’s probably the reason for my new found energy I think.
There’s not much of a limit, if you are feeling good. People have done much more than you’ll ever do in survival scenarios.
The fat guy who walks around the world from day 1 in your theoretical scenario should be concerned about overuse injuries, but not about anything related to fasting.
Just walk/run easy (maffetone style), start at like 20 mins and build up gradually. If there’s a limit for you, you’ll find it, then just back off a bit. You should be able to go for at least two hours though.
Update: I think I pushed my workouts a little too much since the last 2 days and today was super tiring and made me feel very weak. I slept 12 hrs in the day and didn’t do any workouts today. I think I feel a lot better now. Lesson learnt is going forward I will take the workouts very easy :)
I’m not seeing it yet, but I do feel the need to say that there is an upper limit to ketones, but your body only usually gets there if you’re diabetic and under specific circumstances. If it goes too high, you get into a state called diabetic ketoacidosis, which basically makes your blood too acidic and is crazy dangerous.
That being said, if you’re not diabetic, or you’ve already transitioned to a low carb/ketogenic lifestyle, and your body is adapting just fine, you shouldn’t have to worry about it.
But I just felt it was important to mention and I think that answers your question. I hope. Lol
ETA that I usually hear about DKA happening to people on keto, not so much from fasting, though I could be wrong. Just thought that it was a little risky that someone else said there was no limit to ketones, so I wanted to clarify. Personally, I still feel that keto is the most healthy way of eating, especially for diabetes, but it is important to get your body on board, so I believe that people just need to ease their body and stay on top of tracking those ketones so their body can adapt.