KETO Bonking

(Christopher John Howson) #1

Can anybody help me?
Im somewhat confused…

now i was lead to believe that a due to the metabolic advantage that a fat adapted individual exhibits, one could cover long distances without bonking?

Ive been ketogenic for at least 18 months now and consider myself “fat adapted” and well versed in the subject however, it appears i have missed a trick?? i really thought i had this diet down.

There isn’t a day that goes by where i’m not listening to, or reading something regarding the “diet” whether it be success stories, the science of it all or information on low carb performance etc. im immersed in the subject to be honest, but now i need help!

I did my first long(ish) distance event at the weekend, an olympic triathlon (just short of anyway) and while i made it to the end and felt great afterwards (completion time 2hours 20mins) on the drive home i started to feel pretty average to say the least, i realised that this was prime bonking time - about hour three.

now, Ive never experienced “bonking” before so i don’t know what it feels like, i can only guess.
all i know is, is that i felt cold inside, tired, and did not feel like eating.

i hydrated well, prior, during and after.
i had plenty of electrolyte too.
i was in somewhat of a fasted state, but had also drank some pruvit ketones 40mins before.

after the race, my blood sugar was at 4.8mmol.
my blood ketones were at 5.8mmol.

i have been told that these symptoms could be gall bladder / bile related? (body shutting down certain systems?)

i am a lean individual, about 8%BF weighing 72kg on a normal day.

i have another olympic tri coming up in two weeks and don’t want this to happen again.
can anyone shed any light?
do i need “strategic carbs”?

A somewhat confused,
yours sincerely,
performance / keto enthusiast
Chris Howson (the keto house)

(Stickin' with mammoth) #2

Did you experience the bonk during long distance training periods beforehand? You mentioned it was your “first long(ish) distance event” and that you “made it to the end.” Does that mean you’ve never done anything like that before, not even in training? Most of the tri guys and ultramarathoners I know train in such a way that the competition is like any other day for them, they train until it’s easy.

Other thought is to experiment with protein ratios. The body changes, maybe you’re ready for something new.

#3

There are a few confounders that I see.

From what you describe and what people like Mark Sisson and Dr. Jeff Volek describe, I don’t think you are experiencing bonking.

Keto-adaptation doesn’t eliminate the need to burn glycogen, but it does maximize fatty acid oxidation and minimize glycogen utilization, so you can still temporarily exceed your capacity to generate energy and have a period of time when glucagon spikes and you sense a low-energy state during that timeframe at that level of expenditure.

In the thread below @Emacfarland talks about metabolic testing and you might find the results interesting and helpful given your level of competition. In other words, the testing might show that you’re not as fat-adapted as you think and you might be using more glycogen for your level of exertion.

I’m also not convinced that exogenous ketone supplements like Pruvit are a good thing and instead think that it’s better to rely on your body making ketones. @richard makes a good point that the exogenous ketone products mix the left-hand and right-hand versions and our bodies can only use one of them (I think it is the “Dextro” or right-hand version). Instead of Pruvit, I would use something like KetoMCT.

(Guardian of the bacon) #4

At 8% body fat I would wonder if you are running up against your bodies ability to produce energy from available storage. @richard talks about this here. http://blog.2keto.com/why-fasting-is-easier-for-some-people/,

Supplementing energy with some fat during the event may be a necessity.

#5

What you describe isn’t bonking. Bonking happens during a race and it basically means that your muscles and liver run out of glycogen, at that point, the body pretty much shuts the body down in favour of the brain. Bonking feels like you are running on empty, you may get clammy, may feel dizzy, may feel like throwing up, your limbs refuse to output power like you want them to, you feel weeak, you feel like you are running/cycling in porridge . Basically, your brain implements everything in it’s power to stop you doing what you are doing that is using up it precious glucose.

There is no defined “bonk point” as it depends on how much glycogen you have, how quickly you are burning through it, and whether you are replacing it, and how much fat you are burning vs glycogen.

If you completed the race, and felt great, you didn’t bonk. Nor, is there such a thing as ‘delayed bonking’. Your body should have started replacing glycogen as soon as you stopped. And here’s where the problem probably is, your body scavaging itself to replace glycogen. As far as I know, the only place it can get glycogen from is protein via GNG. If you don’t feed it protein after, you might feel pretty poorly as your body scavanges it’s muscles for protein. This is possibly what happened, and easily avoidable by eating.

If you are racing at any sort of intensity, you are burning both fat and glycogen. The higher the intensity, the higher the carb burn.

But even body fat, especially for lean individuals, is not an unlimited resource. You need to be kind to your body and still feed it especially after intense exercise.

I don’t know what you are hoping to achieve by racing a triathalon fasted. And why you wouldn’t eat after a race?

The advice I would give depends on your goals and your philosophy. If you want an increase in performance but want to stay in Ketosis then add superstarch to your pre-race intake. Alternatively, don’t worry about being ’ ‘low carb’ and eat carbs. Just eat some glucose lollies beforehand or during. Those carbs are going to be burnt up by the end. The longer your intense exercise goes for, the more carbs you are going to take in during the race. (This is not for training, but for racing). Most serious low carb athletes adopt a “Train low/Race high” philosophy,

Skip the pruvit ketones. Utterly pointless. Save your money. You’ll get just as much out of a coffee with coconut oil in terms of energy. If you want to take a performance supplement then BCAA’s (amino acids) are going to be far more helpful in assisting the body get through intense exercise.

Eat some fats and proteins after the race. You don’t do your body and feelings of well being any good by starving it. At 8% fat, fasting is counterproductive, as is racing in a fasted state, IMHO.

Most serious low carb athletes don’t share their performance secrets, but here is a good article on a pro LCHF athlete winning the ironman … [spolier: He ate a lot of sugar during racing] https://profgrant.com/2014/03/04/how-to-win-the-ironman-on-lchf/

Anyway, eat more, possibly simple carbs if you are racing at intensity*, and definitely eat some protein and fats afterwards.

Disclaimer: This advice does not apply to people who are not racing or exercising intensely for longer periods. It is perfectly easy and acceptable to exercise for hours without the need for any carbs, It’s also fine to not eat before, during or afterwards (if you don’t feel like it). But, your metabolic needs cycling for 2hrs at 50-70% of your max, is very different to 2hrs cycling at 90% of your max.

#6

Yes, glycogen can be replaced through Gluconeogenesis (GNG), and it can proceed from the amino acids in protein as stated, but also from the glycerol released through fatty acid oxidation as well as pyruvate and lactate.

From breakdown of proteins, these substrates include glucogenic amino acids (although not ketogenic amino acids); from breakdown of lipids (such as triglycerides), they include glycerol (although not fatty acids); and from other steps in metabolism they include pyruvate and lactate.

#7

I really should’ve remembered the other thread below and included it in my earlier reply since there are many good links in there.

One of the main links from the other thread was one included here by @jfricke and allowing for the limit of approximately 31 calories per day per pound of body fat and assuming you’re 170 lbs, that would be about 14 lbs of body fat at 8% which only allows you to access 434 calories per day from your fat reserves and from what you describe, your activity levels exceeds that threshold. On the optimistic side, being fat-adapted minimizes the need for glucose/glycogen, so supplementing with a combination of MCTs and perhaps something like macadamia nuts would be a better fuel source than the Pruvit ketones.

#8

Fasting fat utilization and exercise without fasting are related but different. Also, see my post about IMTG in that topic. Ability to use fat as fuel for endurance sports

#9

Can’t stop laughing at this…bonking in Australia has a whole other meaning!! I opened this post with much trepidation. :joy:

(Guardian of the bacon) #10

Do Tell!!

(Crow T. Robot) #11

I know Richard had some calculations that worked out this way, but I just don’t think it holds water. I thought it was a bit of a stretch when I first heard it on the podcast, and since then only more so. Haven’t Phinney and Volek’s experiments with fat-adapted, lean athletes proved that it’s possible to burn far more than 31 calories per pound of body fat per day? They were burning more than that in an hour, or am I off-base?

(Crow T. Robot) #12

I’ve heard it both ways in the US.

#13

I follow Richard’s logic, but I’m not 100% convinced either. I do believe that there is a limit on how much energy can be released from a fat cell and it might be 31.5 kcal under the conditions specifically tested, but maybe there are other conditions where more or less can be released.

I think I need to re-listen to the podcast and re-read The Art and Science of Low Carb Performance and do some more research among other things.

(Crow T. Robot) #14

Exactly. I think Richard’s logic is excellent. It was just the application of that particular study that was questionable, IMO.

#15

It’s another word to describe having sex…I had the most ridiculous comical image pop into my head when I read the tag line of a gorgeous steak dinner, candles, Barry White playing in the background… :grin::heart_eyes:

(Beth) #16

I wanted to add to this rather old thread in the interest of restarting the conversation. I have had some similar experiences to @Christopher_John_How related to exercise bonking.

I’ve been a cyclist for many years and undertook this woe about 17 months ago. I feel that I am extremely fat adapted at this point. So I too was under the impression that I could exercise continuously without getting that crash that a lot of sugar burners experience if they haven’t replenished their carbs.

I am not particularly lean, probably 25 or 30% BF.

So I’ve biked on many occasions in the past 17 months and the experience has been highly variable. So far, every time I’ve biked, I’ve been keto, very low carbs, either fasted or not fasted. On many occasions, when I rode at a moderate perceived effort, everything has been fantastic.

The times I’ve bonked seem to be consistent now that it’s happened to me several times. I was on group rides where the pace was aggressive and a high perceived effort. Things seem ok at first, then as the ride wears on, I lose my ability to maintain the effort and then start to feel weak and slightly nauseous. Yesterday, I actually had to lay down for an hour after I got home (UGH).

After reading this thread I’ve come to the realization that if I know I’m going out on one of these high intensity group events, I may need to eat more carbs than normal before the ride and bring some electrolyte drinks and carby nuts or other snacks, just in case. I admittedly was dehydrated as well even though I drank a lot of water and took some pink salt prior to the ride. After all this time being keto, saying this just doesn’t feel right to me, but the bonk yesterday was pretty epic.

If anyone has insights into this or strategies, I’d be interested in knowing them.

Thanks!