The Ketogenic Athlete

drink eggsHere in Part IV of the Sock Doc Essential Guide to Carbohydrates I’m going to discuss the hot topic of ketosis in athletes. Ketosis is a metabolic state where the liver takes fat and proteins and produces molecules called ketone bodies to use for energy. Ketosis allows a starving person to survive for days (or even months). Some athletes see great improvements in their health and fitness when they’re in a ketogenic state, while others just feel miserable. So is a ketogenic diet right for you?

This is Your Brain in Ketosis

sugar brainYour brain is approximately 2% of your body mass, though it requires approximately 20% of your basal metabolic rate – more if you’re a thinker. That’s not necessarily a joke, believe it or not. Different parts of your brain use different amounts of glucose, and nearly twice as much later in the day than in the morning. If you’re using your brain solving problems and working mentally hard throughout the day, you’ll need to fuel your head more. If you’re working more on motor control, (say a skill involving precision or balance), then you’ll use less glucose. Personally, I can attest to how much my brain uses more energy when mentally challenged. When I’m treating patients in my office, often dealing with complex problems and biochemical pathways, I can’t go as long without eating some carbs than if I was outside training most of the day. Even though I’m using more energy exercising for perhaps six to eight hours, I feel more fatigued when using more of my brainpower for less time.

Though our brains run off glucose and not fat, they can also run off of ketones as an alternative fuel source. Those who promote ketogenic diets tend to note the fact that an increase in ketones improves the recovery and repair of neurons and increases the inhibitory neurotransmitter GABA. (GABA chills you out and helps you sleep. It’s also the main neurotransmitter which sleep meds and anti-anxiety drugs effect.) Of course, ketosis means you’re burning way more fat, (in the form of ketones), for energy than sugar, and for the most part that’s usually good thing.

You won’t venture into a dangerous diabetic ketosis level as long as you’re producing even just a little amount of insulin. So as long as you’re not a Type 1 or pancreas-about-to-fail Type 2 diabetic, there is nothing to worry about. But to stay in a keto-adaption state, you typically need to eat less than 50 grams of carbs per day if not much less than that; it’s not an easy feat. In this state, the body relies on fat rather than glycogen, and the brain relies on ketones rather than glucose.

People wishing to achieve ketosis also can’t consume too much protein. This usually means no more than 150g a day. Protein can be converted to glycogen and as you learned earlier in Part I, this protein can also be used to make glucose and that would throw you out of ketosis.

Ketones Vs. Glucose: Know When To Say When

athletes-and-sugarSo should you try to achieve this ketogenic state? Personally I think it’s unnecessary for most, but for some people they need to do it at least temporarily to get their body out of insulin resistance. Again, like most things – it’s very individualized. If you’re severely insulin resistant then this might be your way out of it and on the road to health again. Overall, most people could do better, (meaning become more fit and more healthy), eating less carbs. But I think some people tend to go to the extreme and fear carbs when they don’t need to. Most people also fear insulin since everything we read today about obesity, cancer, and pretty much any disease talks about inflammation and insulin. But don’t forget it’s all about making just the right amount. Insulin isn’t a bad guy, just too much of it is. If you don’t make insulin when you should be you’re actually in a more dire situation than making too much and becoming insulin resistant.

It typically takes two to three weeks to really shift your body over to fat from using sugar as a primary fuel source, and this is with a very low carb, high fat diet. Often just tweaking your diet a little bit won’t do the job to make the shift. You have to go to the more extreme for a few weeks, and then you can add in some carbs after that and see how you react to them, mentally and physically. The nice thing about shifting your body from sugar burning to fat burning is that you also won’t convert back to being a sugar-burner if you eat too many carbs for a short period of time. I put many of my patients on a carbohydrate elimination diet to get them headed in the right direction.

Whether your want to be in ketosis or not is up to you, but you should be able to go days without any carbs (other than veges) in your diet. And you should be able to go most days with no sugar other than some fruit. Complex carbs should typically only be consumed when you’re training hard or long, or when you just want to eat them because you want something like pizza, a dessert, or whatever you’re into.

Remember, even if you’re only eating around 2,000 calories a day then 100g of carbs is only 20% of your diet. Hopefully you’re getting the same amount of protein and that leaves the fat around 60%, which is around 130-135 grams of fat. (Fat is 9 calories per gram; protein and carbs are each 4 cals.) If you’re training hard, you’ll want some more carbs. No actually you’ll need some carbs. If you’re trying to go on a ketogenic diet then good luck training hard or at any moderate to high intensity for a prolonged period. You will feel like hell, and you won’t last very long. So if you’re going to try such a diet do it in the off season when you’re building a solid aerobic base or when you’re in a recovery period from training hard or racing.

Comments

  1. Basically N=1 ;) Any special considerations for females? Like Intermittent Fasting is not suppose to be healthy for most females……

    • Not that I know of. Why do you say IF is not supposed to be healthy for women?

      • Stepani Ruper @ Paleo For Women wrote this well researched article that has been sited by a few of the big wigs in Paleo like Robb Wolfe, Chris Masterjohn, Diane Sanfillipo Abel James etc….

        http://www.paleoforwomen.com/shattering-the-myth-of-fasting-for-women-a-review-of-female-specific-responses-to-fasting-in-the-literature/

        Dave Asprey- Bulletproof Executive… I think you drink the bullet proof coffee….

        http://www.bulletproofexec.com/a-bad-combination-for-women-intermittent-fasting-and-paleo/

        Doctors like Julia Ross have talked about it’s effects on thyroid for women….

        • Actually I don’t drink that coffee (or any coffee more than 1X a month for that matter).

          I guess my confusion to your question is that you’re taking about IF here and I’m talking about ketosis. Really not the same, though they may provide some similar results. But they’re different.

          I can see how IF (and a Keto Diet) could cause hormonal problems and other issues in women. I don’t have enough clinical experience to comment and I don’t think it’s right to just make comments off “reading the studies” that are out there – they don’t always correlate with what is seen. I would say though that guys have a lot of hormonal problems too, they (we) just don’t see it as obviously as women for, well, obvious reasons. I would caution a woman to try IF or a Keto Diet as much as I would caution her not too – depends on each individual, their current health, goals, etc.

  2. Hi! What is your opinion on this for diabetics (I am type I)? I have been on no-carb diet for three months in the past and of course I felt great after the initial transformation process (no insulin shots, very nice glucose levels, better overall feeling). How do you feel about such “diets” (it actually could/should become a lifestyle, not a diet) for actual diabetics? I quit because it is mentally very hard to get the right level of vegetables eaten every day, especially during winter, but have played with the thought again.

    • Well if you’re Type 1 and you don’t need insulin shots then you’re doing something special so you should probably just keep doing what you’re doing. Overall diabetics should be consuming less carbs – obviously insulin resistance is what causes TYPE II and now they’re calling TYPE III a type of Alzheimer’s-Insulin Problem.

  3. This is the best summary of the topic that I’ve read to date. Excellent post Doc.

  4. Really enjoying this series. I’ve lowered my carbs and increased my fat as per the earlier article and my MAF test has improved quite noticeably. Since increasing my fat intake I’ve noticed that my perspiration smells more after my daily run. Any thoughts on whether changing the hybrid mix to run off more fat and less sugar could/would result in a change in perspiration odour?

    Thanks, Craig

    PS, where you say people wishing to achieve ketosis also can’t consume too much protein. Should that be “can” consume too much protein?

    • This is from the ammonia forming from nitrogen breakdown from protein. I actually wrote about this (the entire carb series is eight posts long, but I’m not posting any more – you’ll have to wait for the book, sorry). You can either eat more carbs or better yet don’t train to the point where you rely on carbs which your body is providing from protein breakdown.

      Guess I should say they “shouldn’t” or else it’ll throw them out of ketosis.

  5. Jacob Golden says:

    Hi,

    This sounds very much like the ‘Two Week Test’ that you and others talk about and that I’m currently doing. Is the process of going ketogenic different then the ‘two week test’? Also, the way I found out about the ketogenic athlete is through an ultra runner named Mike Morton who just placed third in the Western States 100 mile race. He writes about it on his blog. It showed me that you don’t need to be on a carb heavy diet to be a long distance runner.

    thanks and great site.

    • This is why I mention the TWT in the article. No, it is not the same. The TWT is just that – a test and you can’t have any carbs on the test other than veges.

      • Meghan Kennihan says:

        What veggies can you eat during the two week test? does 30g of carbs from sweet potato count? What about 6grams from cottage cheese……? How strict is this suppose to be?

  6. The statement below in my opinion is false. I run triathlons and have been on an ketogenic diet for two years.

    “Remember, even if you’re only eating around 2,000 calories a day then 100g of carbs is only 20% of your diet. Hopefully you’re getting the same amount of protein and that leaves the fat around 60%, which is around 130-135 grams of fat. (Fat is 9 calories per gram; protein and carbs are each 4 cals.) If you’re training hard, you’ll want some more carbs. No actually you’ll need some carbs. If you’re trying to go on a ketogenic diet then good luck training hard or at any moderate to high intensity for a prolonged period. You will feel like hell, and you won’t last very long. So if you’re going to try such a diet do it in the off season when you’re building a solid aerobic base or when you’re in a recovery period from training hard or racing”

    I’m just curious where you based this statement from. Also, 100 g of carbs (sugar) a day is a lot and in my opinion is why this country is so obese. I also had the impression that you were and M.D., but you’re actually a chiropractor. What qualifies you to give dietary advice?

    • Since I hear the insult at the end here – let me ask you this: “What gives a MD qualifications to give dietary advice?”.

      Next I would be interested in how you train anaerobically and not replenish glycogen stores. But I’m really more interested in your glorification on the medical society.

  7. Dear Dr. Gangemi,

    Reading comments like the one of this guy called “Eric” really makes me sick ! Well, guess for every 100 people that you helped improve their health and live there got to be one foul apple as well. Can´t wait for your book, I will put it right next to Dr. Maffetones !

    Yours sincerly

    Wolfgang (an ultrarunner and HUUUUUUUUGE fan from Austria)

    • Thanks Wolfgang. I don’t bother too much with such bozos. I’m going to hunker down on the book this fall/winter for a spring release.

  8. I disagree with your last paragraph. I train all the time in a ketogenic state and feel much better than when I run on glucose. I am a fitness professional and have even trained on a ketogenic diet for 800m races. My lactic acid build up is not as painful when I am on a Ketogenic diet. Thanks,
    Michelle Berger

    • I’d agree with shorter distances such as 800m but not longer events (5K and higher primarily) that tax the anaerobic system.