We have another special edition of The Kona Edge for you today. Functional sports nutritionist Ian Craig joined us during the 2016 IM Summit to share a few fantastic nutrition strategies for Ironman triathlons. This is a segment of that lecture and deals with what you should focus on in the build up to an Ironman.


I’m going to spend a little bit more time on the performance nutrition today because this is why you’re here, this is what you’ll get benefit from.

Firstly, micronutrient balances because we’re getting a bit more into the quantity, quantitative aspects of nutrition here, whereas the term qualitative onto the functional stuff, so let’s start with your cabs and fats. Those of you who have been following Tim Noakes in South Africa, you’ll possibly resonate with that. He’s gone, he talks about Banting, which is a low carb, high fat approach and firstly he was talking about using that for diabetes, but he’s since gone into sport and said, okay, we all need to be consuming a low carb diet. He doesn’t expressly say that everyone must do this, but he doesn’t not and the perception is that it applies to everyone. He needs to do a little bit rebalancing with his messages and he’s actually caused a bit of a rift within other sciences, other peers in the medical profession, so I just want to show you this one.

Ross Tucker is one of his ex-students and he’s a prominent scientist in South Africa, worked for the sports teams and this is a response to Tim Noakes essentially. His article was, low carb diets, a plea for balance, scientific rigour and death to dogma. If our intentions are genuine and we want the best possible number of people, we’ll see that some people benefit from X and others from Y. If we are rigid and defensive and if we own our own position too strongly, then we make it less likely that this ever happens. These are strong words, it’s just one of the quotes I pulled out from his article and I like the way he thinks,

person X is going to be different from person Y and requires different things. For every person who would come into my clinic who is doing the Banting or the applied Atkins kind of approach, who was doing well and losing weight and had good energy, there would be one or two who would come in who are doing badly and quite a lot who are doing indifferently and that comes into the genetics again.

I use a test called DNA Diet which looks at carb metabolism and fat metabolism and not accidentally, Tim Noakes has been tested and he’s got these carb resistant genes, so he himself does need to be very careful and selective with carbohydrates, but not everyone does. It’s only maybe 2-3 people a year who are actually put on a quite solid low carb diet.

Here’s an example of individuality in a very sports context and the authors of this paper were actually in Tim Noakes’ department. He’s seen a lot of different scientific views over the years, which leads to Ross Tucker to say, well, why are you being so dogmatic now. This cycling study, you’ll see on the Y axis you’ve got time, it was a 100km cycling time trial and you’ll see that most of the times are between 120 odd minutes to 160 minutes. They’re pretty fast cyclists, there’s a pretty elite group of eight cyclists, the left hand column is a high fat diet, the right hand column is a high carb diet.

Essentially what they did was they put on two different occasions, each cyclist had to do the trial twice. On one occasion they did a high fat diet for a week, on 70% of calories through fat, that’s a very high fat diet and then for one day they did a high carb diet which kind of did a quick carb load and then they did the time trial.

The other occasion was a high carb diet, which is 70% of carbs, which is also ridiculously high, but not as far out as the high fat diet, and did that for a week and then did the time trial. I actually see from the graph, mostly the high carb diet, the subjects had a faster, the column on the right hand side is smaller and most of the lines are going downhill. In other words, they took a little bit longer to do the time trial on the high fat, a little bit quicker on the high carb, but you’ve got two uphill lines here, one right to the top and one right to the bottom. Actually the fastest guy in the subject did better on a high fat diet, quite a bit better and the slower subject did quite a bit better as well. That’s out of eight subjects, two of them are what you’d call outliers. That’s a quarter, that’s 25%, so it’s quite significant. Tim Noakes is right, some of us actually do do well on a higher fat, low carb approach, but just we can’t map out everyone.

Funnily enough, the research conclusions from this were that on average, the average statistics were better in the high carb scenario. So therefore we keep with the high carb approach, which was the normal convention in 2006. Individuality, we need to view each person in their own skin.

I just want to go into a touch of physiology to look at fuel supplies and this is fundamental physiology, this has been in the textbooks for decades. Fat, the width of this graph represents how much is available, the height is how fast the energy turnover is capable of. There’s a lot of fat, but it doesn’t turn over too quickly. There’s less carbohydrates, although aerobically you can turnover quite well and then anaerobically there’s not much of it, but you can turn it over really quickly. Something like a sprint you can do it pretty quickly, but there’s not much energy available to do it for long.

Basically something like an Ironman, you are there all day, so you’re not going to be using the red block too much, occasionally a burst up a hill or a strategic try and catch up somebody but mostly you’re going to be in the green and blue sections.

Fat will provide, give or take 65% of your VO2 max, so recreationally you might actually, 65% represents what you might call an easy run or an easy cycle or an easy swim, if you’re doing the Ironman recreationally, then fat will probably provide the vast majority of the nutrients. If you’re doing it more towards an elite standard, 65% is not going to cut the grade, you’re going to be more up into the 70’s. Some people genetically can handle that, can actually push their fat metabolism up higher, but most need a little bit of carb turnover. It’s not a case of, okay, are we just doing high fat or are we just doing high carb, we actually need both and there’s a reason why we have the biomechanical machinery in our body to actually cope with both.

Let me share this slide with you. This is a percentage VO2 max, 25% would be going for an easy walk, 65% , I just explained, is a pretty easy aerobic exercise, 85%, okay that might be a top marathon runner during a marathon, you’re really pushing the pace. You’ll see that the green, the big green sections are muscle glycogen, so there’s nothing when you’re just doing that easy walk, there’s a reasonable amount when you’re doing the 65%, there’s a huge amount when you’re doing the 85%.

Ironman, you’re going to be 65% up a bit, certainly not up to 85%, but 65% maybe into the 70’s. There’s going to be a fairly balanced contribution from the different fuels, you can train the body at a low carb state to use fat better. You can actually push up the purple section of this column more in the blue, that’s the fat component and bring down the green a little bit, but you’re not going to eliminate the green, you still need some carbohydrate.

Let me just talk for a moment about this train low compete high concept. This has been around for a few years. The article that I’ve referenced here was 2008 and it’s a very good article because it goes into the biochemistry of it and essentially what train low compete high does is, you might do a low carb, high fat approach for most of your training period, but then when a competition comes up, you throw in a couple of days of carbohydrates loading and then do the competitions, so it’s basically try and train your tissues to use fat better in a glycogen depleted state but then load up because according to the previous slide, you’re going to need some carbs to have these higher intensities.

There’s pros and cons to this method. The pros are glycogen depletion and increases a very important chemical called AMPK, that then is in monophosphate kinase and basically it’s related to ATP, that’s energy and AMP is a depleted or a used-up ATP energy state. If you’ve got a lot of AMP in your body, that means that you’re depleted in energy. That itself is a stimulus for more mitochondrial, obviously the lower [inaudible 0.35.17] in our cells that produce good energy turnover. That works, but the problem is, the perceived exertion of an exercise bout with a mat workload is much higher in a glycogen depleted state.

If I had two people of equal fitness and I did one on a low carb diet, one on a normal mixed diet and then I send them both out for a 10km run at 16 km/h, the one will probably feel like they normally do, but the other one will feel like it’s really hard work. They might cope with it, but they might not, but it’s a stress on the body to train cause it feels harder and physiologically it is harder, so guess what? We drive up the cortisol levels by doing that, cortisol is your stress hormones and we need a certain amount of cortisol when we’re training for stimulation and response, but if we have too much, it can actually rev up inflammation and it can put a lot of stress on the immune system and that is not something we particularly want to do.

What the current thinking, now in 2016 is around train low compete high is actually due to some sessions in a depleted state. Get up in the morning, have a cup of coffee and go, but don’t do it all the time, because you’re going to actually potentially burn your adrenals and cause problems further down the line health-wise. Use it very sensibly.

The other concept that’s thrown around now is individuality is really important. You get some people, I sort of label them as an adrenal type or a thyroid type. You get some people who tend to be a bit stockier, your adrenal types and the adrenals are stronger, they just seem to be able to cope with more training and higher loads and recover better. They can generally cope with the carb depleted states, but the thyroid type, like myself, tend to be quite slim and prone to stress and if they do too many sessions in a carb depleted state, it can be problematic. Okay, so hopefully that’s just given you a little bit of, most of you will have read about the train low, compete high concept, but hopefully that will give you a little bit more, there’s plenty of reading out there, so do your homework, don’t just jump on the bandwagon.

What I’m going to do now is look at nutrition for your competition. We’ll start with three days out and that’s the time period where typically you might do a carb loading base traditionally, do we still do that? I’m not a big fan of carb loading, per se, I certainly don’t like the body to be depleted of carbs, so there’s old strategies of carb loading where you suddenly are eating pasta and bread until it comes out of your ears.

For Ironman it’s not as critical as a marathon because it’s a much longer race and you’re going to be using fat metabolism much more. Don’t go nuts, what I’ve represented in this table is a couple of different dietary options where there’s a reasonable amount of carbohydrate coming in through our breads, get some rice and maybe some pasta if you’re into that, into the diet, butternut squash, potatoes, but you’re not revving up like crazy and you’re certainly not depleting it either.

They’re just average reactions, but I need to see people individually to understand what they need. The last breakfast, before you go out and commit yourself to hours of hard work, okay, here is what I got off the Ironman [book?] on website, for a nervous belly we’ve got applesauce, Rice Crispies, peanut butter and honey, what does that sound like for a breakfast? That’s simply four different items that have been selected based on their calories and their carbs and their fat content and so on. They don’t go together, it’s not a meal.

For the iron stomach you’ve got oats, eggs, banana, raisins and walnut, again, they’re not a meal that works together. I have a sensitive stomach before a race, I certainly would struggle with that combination. Then we’ve got hammernutrition.com, okay, so we get no calories three hours prior to the race, eating at the time will negatively affect how your body utilizes its stores of carbs, so what they’re recommending, take their product 30-45 minutes before the race. Sorry, we’re doing an Ironman, we need some breakfast. Here’s a couple of examples from me, you can read through these and work out what’s right for you. It needs to have been done in practice, I know exactly the race breakfast that works for me, but it doesn’t work for all of my clients, so I’ll get them to try it in training.

I had one client who did this 200km cycle race and he ate a full English breakfast before. All his team mates were eating Rice Crispies and Cornflakes, high carb with their low fat milk, by 160km, he was laughing, but he’s an exceptional example of a very good, somebody with very good digestion capabilities.

Okay pre-swim, here’s my little tip for any race, it doesn’t have to be an Ironman race, take about 500ml of your sports drink that you’ve chosen, mixed up and just sip it, sip it, sip it, over about half an hour or so and when you sip it very slowly, it shouldn’t push the blood sugars too high, so definitely avoid rapid consumption because if you push your blood sugars high, what’s going to happen? Insulin gets released, it drives the blood sugars back down just before you get in the water and you get into a blood sugar low, which isn’t particularly nice.

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