Tuesday, September 29, 2015

The Low Carb High Fat Cyclist - Perpetual Motion

An update on my experiences with the Low Carb High Fat diet, now that it's almost a year that I've been following it. In the process it seems I've discovered the secret of eternal energy, and through my continuing studies, become further convinced that this is actually the way the human body evolved to be fueled over more than 99% of 2 million+ years of our evolution. That we lost it can only be viewed as yet another part of the saga of our on-going downfall.

My awakening to the health benefits of our ancestral metabolic state, has brought with it the grim knowledge that this won't be welcome information to many. Through blinkered thinking, self interest, and hasty public health decisions, we live in a world that is just so far down the track in the wrong direction. It seems increasingly evident to me that the 12,000 or so years of development of our sedentary culture or "civilization" as we like to think of it, while considered widely to be our crowning achievement, is also at the same time our curse. Author Jared Diamond notes in his great anthropological study The Third Chimpanzee that with the advent of agriculture the average height of populations decreased by 6 inches, and longevity by 10 years. Recent studies on diabetes and heart disease have similar observations. But more on that later.

It's immensely difficult to get through the barrage of erroneous and irresponsible information that is out there, not least of all because so many industries, and livelihoods, are now reliant on the established dogma.

What makes it doubly difficult, even without being constantly bombarded by propaganda, is the harsh reality that most of what we have come to identify as food, is actually better labelled "fun". Our bodies have got used to the sugar-rush associated with eating refined carbohydrates, and our days are organized around the need to satisfy our blood-sugar cravings at regular intervals. I'm aware that a lot of the struggle with the LCHF diet comes from the perceived lack of fun in real food. I mean, the most pivotal social occasions in almost every culture on the planet have evolved to be inseparable with the consumption of sugar and refined carbs. Dietary salvation, it would seem, comes with a certain social exclusion.


One of the most damaging myths in modern circulation, and one that the exercise industry is bent on perpetuating, is that you can basically eat what you like if you have an active lifestyle. I myself used to accept the conventional wisdom that as a fit person I was free to indulge in pretty much anything I fancied in the knowledge that I would be able to "burn it off" later.

The reality is, unfortunately, that we don't lose weight with exercise if we eat wrongly. In fact if we eat correctly we'll reach our ideal body composition regardless of activity levels. Exercise stimulates our appetite as our bodies trigger the impulse to replace the fuel we've used up in energy. In his meisterwerk Good Calories, Bad Calories, Gary Taubes observes that all animals have a central governing system that regulates food intake according to energy expenditure against stored reserves. We humans lose weight if our bodies are able to access and efficiently utilize the stored fat which we all carry around. However, if we feed ourselves carbohydrate, we short-circuit the system. We bombard our blood with an instant hit of cheap and fast fuel - glucose - which our body happily uses for all of it's energy needs.

Glucose blocks the body's ability to use it's stored fat.

In addition, when we have no current energy demands and our blood sugar increases above what we can immediately use, our pancreas creates the hormone insulin which shunts all the blood-sugar to storage sites where it is converted to fat. This creates an immediate need for more sugar. Sugar and modern super-refined carbs start to enter our blood streams as soon as they enter our mouths, so the surges can be quite extreme depending on your body's insulin response. We then experience the sugar-craving which most of us call hunger.  

Insulin also blocks the body's ability to metabolize it's stored fat. 

This yoyo-ing between raised sugar and insulin levels creates the Metabolic Syndrome where the body is constantly craving sugar, which it then stores as fat, but which it cannot then access since insulin controls the release of triglycerides from adipose tissue,. As long as either sugar or insulin levels remain elevated, the fat stays where it is. By eating the wrong stuff we are literally starving our gradually expanding bodies.


Thus you can see that, though we assume that those involved in endurance sports will have efficient fat-burning, aerobic metabolisms, most of us burn sugar rather than fat for a far higher percentage of our overall effort than we expect. When a marathon runner depletes their store of glycogen and blood sugar after about 2 hours of sub-threshold running, their body can't just flip a switch and change to burning fat.

It's an either-or situation. You're either adapted to burning sugar, or your adapted to burning fat. It takes days just to start the transition from one to the other. Even the most highly trained glucose-burner can store only around 2-hours-worth of sugar, whereas even the leanest of us is carrying enough fat to last several marathons back-to-back. Changing that will require re-calibrating our bodies at a cellular level to again use the super-efficient energy pathway we evolved over the past 2 million years as persistence-hunters.

Sport science for the past few decades has focused on finding ways of optimizing the delivery and storage of glucose to enable our glucose-fueled activity to keep going for longer. Only a rare few had the idea that maybe it was better to find ways of tapping into that vast reserve of fat that we all carry. We will all one day thank them. This is their legacy.


In a fasted, or glucose-free state, our bodies will gradually learn to efficiently use the relatively slow-burn option of fat for fuel. Our liver produces Ketones from fat, which serve to fuel the organs which in modern humans have grown used to relying on sugar, and our bodies maximize the range of the aerobic energy pathway so that it becomes super-efficient at metabolizing Triglycerides from our fat storage for use in all activity. It will also regulate intake according to what is required for energy reserves, so hunger is a real sign for a need for nutrition, and not just a craving for more cheap, immediate fuel.

To get there is simple, but will need more than a little will-power, and will require days of minimized carbohydrate consumption. You will crave sugar for the first 4-5 days and you'll be cranky and lethargic to begin with. I achieved basic nutritional Ketosis in the only real way possible - cold turkey - within a week of cutting all refined carbs and any grains or starches. After 4-5 days I no longer experienced the cravings for carbohydrate. Having the strength to cycle at anything more than an easy spin took a couple more weeks to kick in however, as my body adapted at the cellular level, or what Dr Stephen Phinney calls Keto-Adaptation. But aside from some rather pathetic rides it was a fairly smooth and painless transition thereafter. The results on my energy levels and well-being were life-changing.

In my studies I've covered just about everything I can find - from the coaching methods, testimonials and evidence in the field of endurance sports, to the latest revelations in nutritional science. I realize that while LCHF is a path to good health for all humans, the demands of an athletic life deserve particular consideration. My past year has been my testing out of this theory, using my own body.


My presentation here is mostly anecdotal. I don't have the resources to run meticulously controlled tests which might offer conclusive results. But what I've discovered is that I am able to keep going with the same level of energy for a very long time. As yet untested as to the actual range I might have. I have developed the ability to push the pace maximally through training. I do regular rides of over 100km on nothing but water. On longer rides I will eat. I try mostly to keep to the LCHF regime if I can. If I'm in a group that needs to refuel I'll generally go with the flow - it's one of the rare times when you can actually eat most things, simply because the body is already in the metabolically elevated, exercise mode and will correctly utilize whatever you give it.

Beyond a 4-hour ride I will get hungry. Literally just that though. Not lacking in energy or feeling depleted in any way. I haven't actually pushed the water-only test beyond this point yet. The longest rides I've done in the past year are just over 200km, and with groups, so I follow the group dynamic, which means having refueling stops, but I have phased out the use of isotonic drinks even on these rides, and now rarely drink anything other than water. In the past year I haven't ever experienced anything remotely resembling that feeling we call the "bonk", when our glycogen stores run out.


So assuming that I can train my body to maximize it's ability to function within the fat-burning, aerobic energy pathway, there's still the issue of that potential glucose requirement for the higher-intensity effort that is assumed will have to come from the anaerobic pathway which relies on muscle glycogen - a stored form of glucose. In racing, and in training to improve our performance, it is commonly-held sport science dogma that we will need to make demands on this anaerobic system if we are to maximize our potential.


The big question I had when I went into this was how to assess this demand. Much of the literature I was reading suggested that in the fully keto-adapted athlete, no additional carbohydrate would be needed. In fact it suggested that the preserved state of ketosis was ideal for recovery.  Other writings suggest that athletes will need to consume an additional amount of carbohydrate in their diet. Most however agree that there's no one-size-fits-all. The claim is that glycogen will also be synthesized from fat and protein, and at higher metabolic rates in the keto-adapted. Much literature also suggests that we can train our aerobic pathway to be efficient at remarkably high intensities, so that our fat-burnigh metabolism can take care of it all.

I have made the following observations from my own personal experience. This is what I currently believe is working for me, though I'm still experimenting, and I'm still yet to push the boundaries of the experiment in terms of distance, intensity, and (lack of) consumption:

  • When riding 1-4 hours of endurance-based, mainly zones 1-3, but even with a fair amount of higher intensity, my body will not require additional carbohydrates under normal circumstances. I will not need to eat during the ride. My recovery drink will contain some added carbohydrate from fruit, but my meal afterwards with be a standard LCHF meal.
  • If I am to do consecutive days of the above, I will include a little more carbohydrate in the recovery meal.
  • On rides of over 4 hours I have nothing conclusive to offer really, as I haven't pushed the envelope by not eating. Up to now I eat whatever is available on these rides, due to their social nature mostly. I will get hungry at some point, though I haven't experienced any reduction in strength. Convenience and speed of digestion means carbs are the obvious choice. Recovery will involve a similar carbohydrate element to the above.
  • If I train at an intensity of zone 4, or shorter durations in 5 or 6, I will include a similar additional carbohydrate element in recovery.
  • If I train specifically for anaerobic endurance - zone 5 or above for maximal durations, I will include a fair amount of carbohydrates in recovery, and possibly more carbs in a subsequent meal within 2 hours of training.
So I'm still being rather conservative when it comes to recovery. I have so far had little real opportunity to test the full ketosis theory beyond 4 hours. I think I'm still holding onto the belief that, though we may no longer need carbohydrate supplements during exercise, the recovery process from intense effort will demand a slightly higher percentage of carbs than our basic LCHF formula. The test goes on....


Below is the data analysis of a 4-hour ride I did a couple of months ago without consuming anything other than water. I was reasonably well-rested for the ride, so my glycogen stores will have been good (whether I actually tapped into them or not is still unclear). For the last 20km downhill of the ride we went quite hard, in fact my highest heart-rate reading for the ride of 179bpm was recorded during this section. Average HR for the ride was 145bpm (threshold is around 168bpm). My highest average 5-minute power output at 258w was in the last hour, while my highest average for 20 minutes, at 215w, was on the first climb (estimated FTP at 238w). My energy levels were consistent throughout.

I have plenty more of these but they all offer up pretty much the same picture, so I won't bore you with it here.


Crucial to give a picture really, as most people can't imagine how they might eat if they took out the bread, rice and pasta etc. In fact it really is like only eating the nutritious stuff and jettisoning the fluff. You actually eat less in terms of volume. Just more fat.

As an example I covered a sample of my normal diet in my last post about the subject, but to summarize the principles: we're talking about replacing the calories you'd normally get from carbohydrates with fat. The protein content of your food should remain pretty much the same. Fat is denser in calories than carbohydrate so you need to eat less of it. The best fats are animal fats. Other good fats include coconut, palm kernel, almonds and olive. Saturates and Monounsaturates. NOT seed or corn oils. Omega 3s are essential, though not too much. The longer chain Omega 6s only in small quantities.

Those still duped by the Cholesterol myth can refer to my earlier posts below, or should read this or this.

Additional carbohydrate when needed should come from fruits. Not grains or starchy vegetables.

During a ride, if you're hungry, obviously carbohydrate is the easiest food to digest, but as long as you're not about to go "full gas" include as much good fat as you can comfortably digest, and some protein. I've found that half-boiled eggs (with butter?), some fruit, and tea with cream work pretty well, but mainly because that's easily available on most of my rides.

Dairy is awesome, but check that you're not lactose intolerant. Everything should be full fat.

Low fat = high carb.

My favourite recovery drink is full-cream milk and beetroot juice.


The most interesting testimonials will come when those who ride, and win, grand tours are using a LCHF diet. I'm sure that within the extreme parameters of the effect that this kind of brutal event has on the body, things evolve that otherwise wouldn't. I still see top pros in these races obsessed with maintaining their blood sugar, and suffering withering melt-downs when they "hit the wall". That means their bodies are still reliant on carbohydrates as a primary fuel or that wouldn't happen. Of course the rigors of a 3-week race demand ridiculous levels of food consumption, which even then fall short of replacing spent reserves, and leave the athletes under-weight, with impaired immune systems and even reduced muscle mass. I'd be fascinated to learn how a body adapted to ketosis could evolve to deal with this extreme situation. It really is like a complete re-wiring of your metabolism.

While there may be teams or individuals that are secretly applying these principles, to my knowledge it is still at the "secret weapon" stage if it exists at all. I'd say it's a typical case of "you can't add to a cup that is already full". The pros are all advised by their appointed "experts". Very few of the doctors, coaches, and sports scientists recognized (entrenched) within the sport are open-minded enough to completely challenge the prevailing dogma. Couple that with the fear of losing even the slightest competitive advantage, and it should be easy to see why ideas become entrenched.

In fact it was the complete 180-degree turn on diet of one of my personal gurus, and one of the most respected sports scientists, Professor Tim Noakes, that prompted my interest in this food revolution in the first place. He has become an evangelist for this revolutionary cause, and though the book Real Meal Revolution was, until recently, only available in South Africa, it has now been published internationally. The website Real Meal Revolution remains one of the best resources for updates on what they call the Banting diet - the science, the testimonies, the recipes, and the growth of the movement, plus lists of acceptable and prohibited foods. Noakes has converted some top marathon runners and other sportsmen to the LCHF diet, with stellar results.

Of course there are plenty of other age-group and amateur athletes like myself out there already reaping the benefits of reverting to our ancestral metabolic state. Jeff Volek and Stephen Phinney's great book The Art And Science Of Low Carbohydrate Performance was first published in 2012. But for us it's much less of a risk, and we get to try all this out in a relatively non-lethal environment, since we don't make a living from winning.

I think we can anticipate a wave of young graduates from those currently in sports science and medical programs, unable to dismiss the unraveling evidence of dubious Public Health practices, and excited by the real science now being put forward by Noakes and a growing contingent of free thinking academics. These guys will be the coaches and team doctors of the near future.


There's no doubt in my mind that this is the way to go. Whether your purpose is to become a better endurance athlete, lose weight, regain your health, or just improve the quality of your life, the LFHC diet works. There may be those who don't respond so well to it to begin with because of certain metabolic predispositions, but there is a growing body of resources for all of us to find the balance that suits us best.

This is still very much a work-in-progress, so expect more updates. I realise many of you will be hoping for more scientific testing and results. I will get deeper into it, but I'm no lab rat. My main purpose is to open minds to the possibilities. For now I again refer you to a blog post by an amazing Finnish endurance athlete, Sami Inkinen, who has data on a couple of scientific tests he did during his process of training the body to run on the LCHF diet.

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