Ketotic Sport Training

Recently came across several sports articles describing endurance athletes (non diabetic) who train in a ketotic state. This made me think that this could be the ideal metabolic state for those athletes among us with DMI. I am wondering if there are people on this website that keep themselves in ketosis through very low carb diets and how that effects their sport training. Specifically if you are in ketosis will your glucose levels remain constant or nearly so during long workouts as your body is now burning fat and not glucose? Any thoughts would be appreciated.

I keep a low carb diet, 125-175g a day, I have found that I am "slow" to warm up and can hang with the faster cyclists for the first 20 -25 miles. Once my body begins burning the fat for energy I am able to compete for the lead. I find that I am much stronger at 40-60 miles than I am at the begining of the ride. My Dex shows a peak early in the ride as I burn off on board carbs and liver dump, than it flatlines for the end of long rides.
I am still honeymooning and am making enough insulin to deal with the low carb diet on my own, as long as I ride consistantly,(125-150 miles a week) and at a high intensity, I can avoid the insulin injections.

Interesting… So that’s what I was doing all summer long! Takes longer to warm up but still have the reserve energy even after bicycling and running to go for more punishment…

Found a balancing point for glucose levels, not spiking as much in lows, 4’s, got 5.4 after a couple of hours exercising, consistently. I guess a combination of low glycemic carbs and fatty proteins works for me!

Go figure things we do to ourselves without knowing it! :slight_smile:

when i eat super low carb (30-40 grams a day) i can do long runs without droping low and without needing to eat food to maintain energy- i have a marathon coming up mid Oct that i plan on eatting this low carb during the taper so that race day BS is not an issue (if anything i have to make sure i dont drink sport drinks becuz even though i am running it will cause a huge spike) right now for training i run every other day and i have a lot of carbs right after the run but the rest of the time i only get carbs from nuts or veggies

I am still honeymooning, too, but though I'm not running or cycling long distances, I do dance exercise, which is pretty intense. I am able to do two hours of exercise and up to three hours by eating things like eggs with avocados, cheese in the microwave, almond butter on flaxmeal, etc. I carry a sugar spray in a fanny pack that I take to class, and when I've done three hours of exercise, I bring another water bottle with 2-4grams of carb , a vegetable powder. Weights tend to raise my bg. I come home about 95, and don't drop for at least an hour or two, though I usually eat something when I get home. I'm on my third year of LADA without insulin, but I even joined a secondary gym on a Groupon to get enough classes. My bg are 85-95 surrounding exercise. How do I know I'm in ketosis? Truthfully, I've been low carbing and exercising this way for three years, and I'm scared of the way that I felt consuming carbs. I get thirsty if I eat too many low carb vegetables before I work out for the first five to fifteen minutes depending on the intensity. After that, the thirst goes away. I try to consume some extra fat before I exercise, but I don't know what I'm doing. It just works for me.

During a recent six hour endurance MTB race, I carried hard boiled eggs in a jersey pocket and consumed them as needed for food intake. I did drink G2 gatorade, cut in half water, for hydration. If I only eat carbs at a meal I spike, if i only eat protein I spike, if I balance protein and carbs bg's are stedy.

read this guys stuff at the eating academy - great stuff- forgot to mention i pump with cgm now n then

Dear SOT 1, great link! It has answered pretty much everything I was wondering about. Although Peter Attia is not a diabetic, I think his experiences are transferrable. Hope to pick up the book by Phinney and Volke soon. I have gone ketotic over the past week after eating low carb (60-80 gms/day) for the last several months. Now about (20 gms/day). So far better BS pre/post wk out and no need for bolus insulin for 1 week! One of the most interesting things I have found is that after a 2.5 HR bike ride this weekend, my BS was 55 when I finished with no signs/symptoms of hypoglycemia. I suspect as I was fueling with ketones my Body does not mind these lower levels. Well early days, we’ll see what the weeks ahead have to offer. Cheers

I've read just about everything Phinney has written and also had the opportunity and privilege to have an extended internet conversation with him regarding low carb athletic performance. One of his assertations, that I'm still a bit skeptical about given findings on enzyme actvity in the glycolysis pathway in response to low carb diets, is that a low carb diet will result in a more efficient use of glycogen.

I think clearly current research shows that endurance athletes can benefit from low carb diets. Certainly there is no reason for endurance athletes to avoid them IF, and it's a big IF, they take the time to supplement properly. I would say that's one of Phinney's most compelling findings.

Given the benefits to BG control from low-carb diets, there is no reason to think that diabetic endurance athletes couldn't also benefit if proper attention is paid to supplementation.

correct about the supplement - i really have to make sure i get enough salt or i get head rushes/lightheaded - this is something Peter Attia gets into a bit-

congrates on finding somthing that is working- i too find my BS is so much better when I am ketonic - and i too find the lows not an issue like you said with the 55 not being bad- i think becuz we are burning fat its not a fast drop which i think may be the reason for the signs/symptoms- keep rocking the Low Carb

Yeah, anectdotally, I have to agree with the idea that BG trend, as much as BG reading, affects performance.

I don't low carb but I notice that a hypo is not a hypo is not a hypo. If I'm under 60 and the BG is stable or even dropping slowly, I can keep working out with a minimal affect. If my BG is dropping fast, even BGs in the 70s, certainly the 60s, will practically stop me in my tracks.

As far as supplements go, what do you do? Just salt or a Mag/K supplement also? Where I am living, bullion cubes don't exist and I don't really have the time to make my own bullion. I haven't really felt the negative side effects described in going ketotic and I suspect it is because I have been adapted to low carb for so long but maybe I am just honeymooning.

You both may be right about the lack of a hypo response as a result of the slow onset versus feeding off of fat. I'll have to test this down the road (no pun intended) by doing a longer ride and seeing if BS stabilises at some point or continues a slow descent to trouble territory. I guess I am hoping, although admittedly skeptical in the theory, that BS will stabilise at some point and I could do a long distance race without needing to be concerned about fuel or BS levels.

Yeah, I'm not sure about being able to continue working out for an extended period of time with a hypo.

I'm neither low carb nor an endurance athlete. I do a lot of explosive, anaerobic training and I feel that keeping my muscle glycogen reserves topped off is more important than the minimal amount of fat I may or may not burn. Muscle glycogen does not contribute to BG as it's being used so it seems like as long as I have a functional amount of circulating glucose, I can get through a workout.

Ultimately, whether your ketotic or not, it will be your glycogen reserves that will determine how long you can work-out, not fat or ketone reserves.

yah i never had "negative effects" mainly just when i drink too much coffee and water i need to make sure i add some extra salt to my eggs or chx or beef - yah I guess supplement is a miss leading word - i dont supplement - i just meant i add a lot more than normal because without all the processed food my salt intake is down --another interesting thing i have been messing with is Mark's Daily Apple says we normally drink too much water and i used to drink a pot of coffee and 130oz water a day- i have now been doing 1/2 a pot of coffee and maybe 90-100oz of water and the head rushes have seemed more rare

"Ultimately, whether your ketotic or not, it will be your glycogen reserves that will determine how long you can work-out, not fat or ketone reserves."
I find this statement difficult to take at face value- before i could disagree i would have to look into it more - but i know that when i fast my BS is level and yet I have fasted long enough to were glycogen reserves should have been spent (i sometimes work out in a fasted state) -this morning i did an easy 2.5 miles but had not eaten for 33 hours and returned with the same level BS i left with- only had bacon and eggs (no real carb effect and maintained BS through lunch)

My own experiences suggest the level of intensity of training vs. the glycogen reserves affects my bg’s directly, just depends on the individual as I do more at anaerobic levels than aerobic, just eat differently towards what I am focusing on that day.

The fact that exercise is glycogen limited, not fat limited, is a pretty robust finding in exercise physiology across a number of different study models and conditions. The bottom line is, when you deplete glycogen, you bonk regardless of fat reserve.

but i know that when i fast my BS is level and yet I have fasted long enough to were glycogen reserves should have been spent (i sometimes work out in a fasted state)

I've definitely exercised after fasting and, back in the days of NPH, I'd have such bad numbers in the morning that I'd regularly exercise before breakfast. Fasting, under usual conditions however, would not deplete glycogen reserves and an easy 2.5 miler probably wouldn't do much to dent glycogen reserves even either, even on top of fasting.

If you think about marathoners hitting the wall and bonking at the 25th to 26th mile and you start to get an idea of the type of effort it takes to deplete glycogen. As a sprinter, it would take something like repeat 400s at 70-80% effort on one day followed by a hard workout the next day to start to feel the effects of glycogen depletion.

Low carbers in ketosis, of course, have low glycogen reserves to start out with which is what puts them in ketosis in the first place. However, this is why Phinney suggests that low carbing somehow makes glycogen use more efficient to explain why low-carb endurance athletes don't suffer decreased performance despite the fact that 1) muscles are glycogen limited, and 2) low-carbers have lower glycogen reserves.

- in Regard to your reply to my reply i must reply with

" this makes a lot more sense, thankx for putting that out there- yah i guess i was not thinking about what it would take to run me out of my stores *esp since right now my body is trained to hold onto my glycogen with my training for a marathon - thankx for spelling it out maybe next time i will think through things a bit harder before posting"