When you are on the bike, there won't be a huge time difference if you're racing on the flat, where absolute power will prevail. But if you go on a hilly course, then we have to think in W/KG, and here, any extra gram is making a difference. Cervello bike manufacturer did a study a few years ago comparing two athletes with 2 kilos difference sitting on the same bike model, the course being 40 kilometres with a constant 3 per cent grade. The final gap time of that 71-minute ride was 36 seconds, which equal 162 seconds for an IronMan 140.6 bike course. It's a lot, but nothing compared to running.

In 2006, a University of Dayton runner physiologist named Paul Vanderburgh decided to devise a calculator to equalize performances among runners of different weights. He called it the Flyer Handicap scale²What's your ideal race weight ? - Runner's world[/mfn], and you can find a lot of versions on the Internet²Weight vs Pace calculator - RunBundle as a “pace versus weight calculator”. He estimated that any athlete will see their speed increasing by almost one per cent for every percentage of weight loss. For a kilo, the difference on a marathon for the same power of your human engine is about 120 seconds. Yes, you can shave off 2 minutes of your marathon time with just one kilo less. The tricky part is to avoid excessive weight loss, resulting most likely in compromised muscle mass, but it's doable.

Last but not least, any weight loss will directly impact your VO2 max, as it's expressed as the rate of millilitres of oxygen used per minute for each kilogram. Everything being equal, the lower your body mass — and not muscle mass — the higher your VO2 max. So that's something else to consider when we discuss the weight management topic, especially for athletes over 35 years old where VO2 max decreases by a steady rate of 0.5% per year. Apart for aliens like Eliud Kipchoge apparently, who still sits on a 88 VO2 max, being the same age as me. Life is so unfair. Back on the topic, I truly hope I convinced you that bodyweight is the key element to your race final time next to training and, unfortunately, some talent.

So what's the secret recipe for losing weight ? Plenty of things.

In training nutrition

There is one single rule to live with at all cost : don't get yourself in a spot where you feel you can faint at any time during your training. Nutrition is a key part of your progress while in training as you will need to absorb whatever is necessary for your body to recover in a proper way to avoid injuries or even worse in some cases, over-training effects. Not to mention your general mood and fatigue that will definitely prevent you from training at your best level. So I can't stress it enough : eat whenever you feel you need to eat. It's that simple.

Living by this rule doesn't mean you have to eat stupid things, though; you need to focus on what's core to help your recovery and in training block performance. I was thinking about sharing with you a typical week's meals, but this would be pointless as it would not be accurate enough as it was directly linked to my training load.

Instead I would prefer to give you my general guidelines :

• No sugar. This is so utterly obvious, but it's true. Remove sugar from everything you can, apart from electrolyte drinks and workout gels which are absolutely necessary for long time effort. It means also to forget about desserts and ice creams, and this is was mentally so painful to live without chocolate cake, which is actually my favourite thing ever.
• No dressing. I learnt to live without dressing for most of the year, and I can see it was way harder than I thought as in our society we are used to eating almost anything with vinaigrette, mayo, ketchup, whatever... These are stupid calories, and won't bring anything good to you.
• No junk food. That general expression has a lot of different meanings, especially for the high-end age group athletes whatever the sport. Fast food is the first thing that would surely enter into my mind, but I could fill up on pizza for example, or any ready-made meal full of food preservatives. Eat fresh, eat a wide variety of food.
• No alcohol. Surprisingly it was quite easy for me to follow this rule, despite being a solid social drinker before starting my triathlon journey. It's just that if you do your training block the way intended, your body will just ask for water. Even though I was saying to myself on a rest day why not go for a beer, most of the time my body was actually commanding me to not do so. Alcohol is truly awful for any athlete, as it acts as a diuretic making dehydration more likely, and by not allowing your liver to produce its usual glucose level. You can feel the effects of binge drinking on your body performance up to 5 days for the record.

Raclette is definitely my favourite cheat meal and was part of my well being, like seriously.

Taking into account these elements, my in training daily nutrition was probably vastly different from a regular individual as it was focused on carb loading to help sustain my efforts :

• 70% carbohydrates. The basic of any endurance athlete, stored in the body through muscles and liver as glycogen.
• 15% fat. Despite behind way behind the carbs, it still come as the second most important source of energy for endurance athlete, stored as fatty acids that we'll discuss later in that chapter.
• 15% proteins. This is not really of any help during any endurance effort, but it's utterly important when it comes to recovery as it's the core element of production for cells and therefore muscles.

Yeah... with such splits I knew everything about any pasta or rice brand in just a few months. Carbohydrates are the key to everything, and you should make sure your intake is well balanced with your planned efforts. You can easily find on the Internet plenty of cooking recipes for endurance athletes, but if you want to save some time, I can recommend you Racing Weight Cookbook from Matt Fitzgerald. That said, being serious in nutrition is utterly important to perform and recover properly, but it shouldn't prevent you from getting some excitement from time to time, otherwise you will most likely just turn completely nuts. I was allowing myself a shit meal at least once a week, usually on my rest day on Friday because I could afford any digestive system issue anyway. I would go full ham on pizza, burgers, cheese raclette — sorry for my non French friends, but I can't translate this — or chocolate cake, possibly some social alcohol drinking too. Whatever I felt like, apart from sugary drinks like Coke that were really not worth it.

We also have to discuss the dietary supplements, which is a topic among a lot of athletes. Either vitamins, antioxidants, or creatine. I won't elaborate on this because this chapter is about to be a long one already, but if you're living in a healthy way with a diverse diet, you'll have everything you need for your daily intake. There might be an exception for vitamin D, that we might lack and really need as athlete when living in countries where winter is a real thing to deal with. Creatine on the opposite can be useful to help in the recovery process, but only when dealing with intervals workout, and in a reasonable way of 5 grams per day.

A decent life deserves morning coffee until you prove me wrong.

What about coffee, as most triathletes have an addiction to it ? There are a lot of articles around the Internet about the pros and cons. For myself, it always worked well, and quite frankly I don't see myself going for long training or a race without a shot of espresso. I understand that for some people it might lead to an instant toilet session, but I think it relies on you to know your digestive system. The only certainty is that caffeine can really help in the recovery process, because it increases the body's absorption of carbohydrates along with the conversion of glycogen.

Finally, race weight is really where you feel great in your workouts and races while not playing with your health. If you're dealing with recurring injuries for example, you're definitely doing something wrong as you don't give enough fuel to your body to adapt to training. I've been in the making for a season only, but it appears that race weight just comes naturally over the course of good nutrition, and smart training.

Pre-race nutrition

I usually shift to a new nutrition gear about 3 weeks before the race. At that point the countdown is on and as the tapering phase is slowly kicking in, so I can start a diet that is allowing me to lose weight enough to match my race weight target without compromising my training performance and recovery. When I say “compromising”, I'm obviously talking about muscle loss, that you should avoid at all cost ! It happened to me once, and I can tell you it's an absolute nightmare as you just feel like that average chimp again, not able to match power with your cardiovascular system. The tiny line to play with is your BFP — body fat percentage —, which the need of could be quite different from an athlete to another one, from one sex to the other.

Refueling straight after a hard training session truly helped my body to recover faster ahead of my second session of the day.

The purpose of this blog is not to discuss the history of the world — thus once you're retired and have some time ahead I'd suggest you read the bestseller Sapiens : a brief history of Mankind — but we have to acknowledge that living in a Western society full of abundance, we're just eating and stocking up too much body reserve leading to solid weight gain. We have to maintain some common sense though, and to understand that keeping a part of BFP, is utterly important for any human being, especially athletes. A lack of calories will inevitably lead to injuries, muscle loss, and... body fat retention. Yes, indeed, if your body is starving to death, it will do it's absolute best to hold on to any intake by slowing down the metabolism, blasting off muscle tissues too demanding in energy, and storing fat as much as it can. This can cause an ugly cycle called the “relative energy deficit in sports (RED-S)³The Relative Energy Deficit in Sports - Wikipedia”, so be aware when you get in a caloric deficit to have sufficient fuelling to avoid the opposite effect sought.

There is no rule that can apply to everyone, but the bare minimum is to aim at least for a BFP of 5% when it comes to men, and 12% for women. Keeping this information in mind, the vast majority of my weeks close to a race were looking this way :

• Low carbs training. Within a few days, I start to process my morning training without any breakfast prior to it. Most likely on the home trainer so I can keep a banana next to me in case of a sudden bonking. This force your body to burn your body stock of glycogen, it's very effective. It's also great training for race day in case of you missing an aid station or forgetting a scheduled snack.
• Daily diet menu. My daily menu is by then drastically reduced to the most essential elements allowing my body to work. Starting with a banana and protein shaker after my first morning workout, then usually 150 grams of white rice with one egg and a yoghurt for lunch. Two bananas throughout the afternoon whenever I feel hungry. Finally 130 grams of wholemeal penne pasta with a 3-egg tomato and cheese omelette in the evening, along with a 0% fat yoghurt. That's roughly 2,000 calories a day so usually a 1,000 calorie a day deficit for someone of my fatness. Yes, I acknowledge it's a lot, but it's working for me.
• No more shit meal. When you put yourself on such a diet, any extra intake will lead 100% to weight gain, so you must be extra cautious until the final days prior to the race. Stick to your core food supply, it's just a matter of a few weeks. Same obviously goes for alcohol, just forget about it.

I won't lie by saying I was not feeling hungry most part of the days, but it was sustainable for me, and I was never in a spot where I was feeling like bonking or fainting as I was always timing my calories intake as perfectly as possible. I think the hardest part was actually to pass in front of my next-door pizzeria every evening when coming back to home. Oh gosh, that smell...

Losing weight is all about mathematics : if you burn more calories than you take in, you lose weight. « With self-discipline all things are possible. » — Theodore Roosevelt

Race nutrition

Making it to the start line of an IronMan 140.6 is already an achievement in itself, because if you did your training the right way you know how much sacrifice you made. It’s a once in a lifetime journey for the most of us, yet I noticed that a lot of athletes are just ruining it by failing their hydration and nutrition execution throughout race day. I’m one of those guys who believes that it's the fourth unofficial sport of long-distance triathlon, and probably more vital than some of the others like swimming. Indeed, being able to sustain a 10+ hour effort and a 9,000+ calories loss is a huge undertaking that will require your body to function at 100%. Not at 99%, 100%. That’s why weeks ahead of your race, your nutrition & hydration protocol should be part of your workouts; you must ensure that you won’t be bonking or dealing with GI — gastrointestinal — system issues. “Training the gut” as we call it is mandatory if you want to show up on race day, and I’ll give you full details on my nutrition strategy I improved over time.

But before tasting that first liquid gel on the bike, your specific race nutrition protocol should already have started some days ago, ideally 3 to 4 days before. The so called “carb-loading”. Some are saying it’s a myth; truth is it isn’t. The first one to prove it was Swedish researcher Bengt Saltin⁴Carbo-Loading is Dead. Long Live Carbs ! - Medium in the 70s and the point is to raise the level of glycogen in your body — liver and muscles — to such a point that it will prevent, or at least delay any hypoglycaemia. When the race is on the Sunday, I usually started this diet on the Thursday. From that moment, I was only eating durum pasta with cheddar cheese, bananas, and some whole-wheat bread with honey after my first workout of the day. I never raised the number of intake total calories compared to the previous week though, and that's for 2 reasons :

• Glycogen can be pretty sneaky, because when it comes to the chemistry process, one gram of it will associate 3 grams of water. So if you just overcharge your pasta dish, you can easily gain a kilo in just a couple of days.
• Your extra compensation of carbohydrates is already reinforced by your tapering phase, allowing your body system to stock up way more than usual with the same amount of calories.

The classic pre-race combo, I never made any exception to it.

On the last dinner prior to the race, I keep it very simple with 140 grams of spaghetti only, because I want to make sure that I won’t feel too heavy and not able to sleep when going to bed. On top of that I’m drinking a powder of whey protein mixed with a Precision Hydration 1500 electrolyte — I will elaborate in the hydration part. When I’m waking up a few hours later on race day, I make sure to set the alarm clock 4 hours before the start. Before taking my shower, I straight go for a solid breakfast made of 120 grams of white rice with another whey protein powder mixed this time with a Precision Hydration 1000 electrolyte, the total fluid being 0,5 litre. Sometimes I was not able to eat or drink anything, so I'm just listening to the needs of my body; the idea behind this morning meal being to complement the glycogen level of my body system lost overnight. I still have usually one hour and a half at the apartment, so I take full advantage of it to make sure I go to the toilet as much as I need during that time. Just before leaving for the race, I grab that much controversial espresso coffee. I'm finally ready to go. Approaching the start time, I try to avoid drinking too much as I sufficiently did during breakfast, and will be able to drink again once on the bike. Maybe a sip of water, but that's it. Not eating any more that's for sure.

Ready, set, go, the race is on and with it a complex and specific nutrition protocol to understand :

• When you are doing physical activity, you just can't imagine how much blood is turning into gold for your body : skin to help dissipate the heat, muscles to bring oxygen for creating energy, GI system to work on food absorption. It's literally a trench war inside you, and your body will eventually have to make choice. So the basic principle to keep in mind is that when intensity is going up, the absorption capacity is going down.
• Following the previous principle, your nutrition should be, must be, the most efficient for your GI system to process. So I can’t be more clear when I say that liquid food is key, especially when aiming for a #SUB10 performance where you’ll play at a higher intensity than an average IronMan 140.6 athlete — as seen for the IF in the data chapter. Solid food is simply a waste of energy for your body to break it down.
• The GI issues are happening to a lot of athletes in the longer triathlon distance, that feeling of being bloated and nauseous. It's especially the case during races taking place with particularly hot conditions, because as the cardio is going higher than usual to evacuate the heat, the blood flow to the gut is compromised. So its ability to process the food and fluid intake is disturbed by the temporary low blood flow, and what has to happen, happens... it's getting out in one way or the other.

Both my gels and electrolyte drinks have been proof tested multiple times during my long rides and long runs, in a lot of various conditions. I tried almost all brands on the market, and decided finally to go with the American brand GU Energy. They are offering a wide range of tastes — with or without caffeine — along with some “extra” gels designed especially for long-endurance activities. Each single gel was providing 100 calories, and if you’re going with the established mantra that you need to go for 3 to 4 calories per kilogram of body weight per hour, it means roughly 30 gels if you’re aiming for a #SUB10. Quite frankly, good luck with this, as I’m nowhere near able to “eat” 30 of those things in that amount of time.

For my #SUB10 attempt, I prepared 14 gels divided this way :

• 10 gels for the bike course. I actually planned to eat 8 gels, one every 40 minutes. 4 gels were the regular model, 3 others were from the Roctane line of GU Energy — providing a double quantity of amino acids and sodium — and one was a Roctane with caffeine that I used around the end of the first loop. I kept 2 spare gels in case of sudden need or one getting out of my hands while grabbing it.
• 4 gels for the run course. The goal was to chew 4 gels, one every 40 minutes. 2 gels were regular mode, one was a Roctane, while the last was a Roctane with caffeine. No spare gel as you don’t buy a pair of Vaporfly to save precious grams on the run just to add up some straight behind with gel. In case of something going wrong, it’s way more easier to grab what you need at any aid station.

The bike leg should account for 70% of your total calorie intake, and there are quite a few reasons pushing for that :

• That's when your body system is still fresh and the most capable of absorbing food without general system stress causing GI issues.
• That's when your cardio should be low enough — that intensity thing we discussed earlier — to give a proper treatment to your fuelling.
• That's way less stressful and traumatic for your body to eat on the bike rather than on the run.

I'll give some of my intake timing tips in the race chapter, but that gives a total of 1,400 calories, which could sound not enough at first sight. You have to make the split of that total to understand there is everything needed :

• 1080 mg sodium — 40% of daily value
• 276gm carbs — 96% of daily value
• 78gm sugars — 156% of daily value
• 300mg calcium — 30% of daily value
• 70mg caffeine — still far away from my daily value unfortunately

My nutrition & hydration packed for Challenge Almere-Amsterdam.

An even more important number to keep in mind for later usage : each gel provides 418 kJ — kilojoules — of energy, and we'll come back to it in a few lines. For now as you can see with just 1,400 calories, I'm fulfilling quite some body need, even though you can't compare the standard DV — daily value — with the one of an IronMan 140.6. Some of you might notice two things though :

• I'm still far away from my sodium DV, something that will be addressed in the hydration topic.
• There is no protein intake, that's why I'm always sticking with a protein shaker before the race.

I think this is the sentence I've said the most in this blog, but again : this is highly individual, depending on so many factors that I just can't list them all. You'll have to make a lot of tries in your B races to figure it out what's working the best for you. Do not leave your nutrition strategy to chance, or you will eventually enter in a bonking process, and at that point, it will just be too late. The concept is fairly simple to understand and has been detailed a lot over the past few years : when our stores of glycogen and glucose are exhausted, we will start to use our body fat — fatty acids to be exhaustive — but that process will require way more oxygen. Other things being equal, the oxygen used will not be able to be used into our legs, meaning far less power in the legs, and you up for one of your biggest disappointments.

Hydration

I had the chance to write quickly about it in my #SUB10 Journey chapter, but during my first IronMan 70.3 at Indian Wells, I completely bonked on the run course. This is because my hydration protocol was simply nothingness, apart from drinking water from time to time. Some would say that without electrolytes, no salvation. I remember watching Kona in 2018 — I was a newbie without any race under my belt at that time — just to watch Lucy Charles missing a hydration bottle at one strategic aid station. The commentators were buzzing about how dirty it could turn for her in a few miles if she hasn't anything to drink. In general, the more the distance, the more the potential for a massive hydration fail is high. I think that is even more important than nutrition, as the line before going off the track is very small. Most research suggests that performance starts to decline after you’re more than 4 per cent below optimal hydration.

I won’t elaborate much, as this chapter is already long enough, but what’s the point of getting your hydration right, and just not stick to water ? Well, having enough sodium and electrolytes in your body is helping it to maximise the blood volume and therefore the cardiovascular function, leading to a better capacity to get rid of the heat produced by your muscles. The cooler your muscles, the less the fatigue and the possible cramps, the better the performance.

It has also been proven to avoid overhydration — the scientific name being hyponatremia — which happens when « a dramatic dilution of sodium (salt) causes an athlete's internal water regulation to go out of whack. Cellular swelling ensues, often accompanied by nausea, headache, a drop in blood pressure and energy, weakness, and even seizures » according to the National Kidney Foundation. I was quite amazed to read in a study that during 2015 IronMan Frankfurt around 10% of the finishers were actually in a hyponatraemic state ! One athlete out of ten had over-consumed water without enough sodium, leading in the best case to a significant drop in performance, and in the worst case hospitalisation !

It is absolutely mandatory to know the aid stations position on the bike course to not miss your chance to refuel !

So what are some general rules of thumb to follow to avoid major issues with your hydration, and that could fit for most of us ? Well, I tried to make a shortlist :

• Have a pre-loading party. I was talking in the nutrition part that I was actually pre-loading the day before, and the morning before a race with a mix of electrolytes. It’s hard to say if it’s really effective — there’s evidence, but not enough yet — but it seems that adding some additional sodium before a long effort is increasing acute fluid retention, thus improving your endurance. This is especially effective in the heat, which is often the case of a long-distance triathlon as it’s done usually during summer, and throughout the day. That being said please don't misinterpret my words : drink normally as you would on any random day, and just add some electrolytes. Don't start to increase your fluid intake, it could literally cause the opposite effect by diluting the body's electrolyte level before you even start your race effort, leading to a hyponatraemic state.
• Don't flood your body. You can't absorb more than 500 ml per hour, which is usually the size of a standard flask, so stick with this rule and you should be more or less fine with various problems, including too many pee breaks.
• Time your hydration like a Swiss clock. It's pretty easy to get slowly dehydrated on the bike, when you're cruising at 35 km/h and can feel the fresh air getting through your skin. Most of the GPS devices now have alarm functions, so just set your alarm to whenever you need to drink a slip in your protocol. For me it was every 20 minutes, and I made sure to respect it even though I was not thirsty, as long as it was not more than 500 ml per hour.
• Alternate your hydration. To avoid GI system issues, you must be smart and not stupidly top up electrolyte hydration with gel for example. So you have to carefully plan your nutrition strategy ahead of the race. If you know that at 60 minutes you'll grab a gel, make sure that you mix it with water and not an electrolyte drink.
• Save yourself with a sodium pill. If you're in a particularly hot conditions on your race day or if for any reasons you didn't manage to get your dose of electrolytes, it can just save your race to keep a sodium pill with you packed in some plastic wrap. I had one for both IronMan Switzerland and Challenge Almere-Amsterdam, and if I didn't felt the need to use it on my first one, it was the case for Almere. Jumping off the bike, I was sweating a lot and missing the last aid station on purpose — I was finally catching up with 2 others riders and I thought more important to have them as “pacers” given my fatigue, so I decided to stick with my last bottle of water — I thought it was necessary to avoid any bonking or cramps early on the run so I just swallowed it.

My hydration strategy is a puzzle that took quite some time to fit together, and I'm sure I still have some room for improvement over the next few years. I'm someone who could be classified in the “heavy sweating” category — I'm ranking among the kind of guy who can have a sweat loss of 5 litres on a hot day marathon —, so I had to work way harder than anyone else on that topic to make sure it wouldn't ruin my races and dreams.

I came out with this simple formula :

60 minutes = 17 gram carbohydrates/500ml = 65 calories = 272kJ

I found this intake to work well during my races, being the perfect addition to my nutrition. Some would say that I could just stick to plain water and go only with a larger nutrition protocol, but nothing can beat an isotonic drink. You probably heard that “isotonic” word hundreds of times without knowing what it really means. It's a shame, because it's awesome : being isotonic means actually having the same osmotic pressure as the blood plasm, so nearly an instant transfer to the blood as the body has a minimum process. Awesome, as I said. This is why electrolyte drinks are mandatory in any endurance strategy, as it's way more forgiving than nutrition.

Shifting to the kilojoules

So far I've only discussed the TSS as the main reference that should drive your training and therefore race effort. But the truth is that something else has been out there for a while already, and that's the kJ — kilojoules — expenditure. I again quite honestly don't want to go into the details because it just would be too long, but take it as the measurement of the work demand you're doing. So why am I suddenly coming up with new data to watch, when we already have plenty to live with ? Errrr... Because this one can rely on your actual physiological demand with your actual nutrition and hydration demand. Isn't that awesome ? I'm pretty sure you might indeed have already heard that any food and drink can be easily converted into kJ with that formula :

Calories = Kilojoules x 0.239

Please note that here we talking about calories, and not kilocalories which are on our everyday use. Shifting to kJ is already an advanced technique I'd say compared to the average triathlete chimp nutrition plan, as it can help to precisely plan the load effort you'll do in every part of the race, and thus the correlation with your nutrition and hydration strategy. It can give some headache on such a long event like an IronMan 140.6, but I will try to break down my logic the best I can in the next few lines.

First, you have to calculate your expectation in terms of timing for each part of the race, and that can be done with these formulae :

Swimming energy cost in kJ = 0.55 kJ x Weight x Total time in minutes

Bike energy cost in kJ = (Total Time in seconds x Average Power)/1,000

Run energy cost in kJ = (Total Time in seconds x Average Power)/1,000

Please note that as we don't use power for swimming, this is a formula that would match an endurance pace like an IronMan 140.6. On the other hand you'll notice that I'm using power as well to calculate the run energy cost. If you can't compare them, the human engine limit still sits at 6.4 W/Kg FTP for both as we saw in the data chapter. In case you're not using power for the run — yet — I got you covered with this formula, which like the swimming one, won't be as accurate without power :

Run energy cost in kJ = 0.98 kJ x Weight x Distance in kilometres

I was using electrolytes whenever i felt my training session would involve solid sweating, rather that just focusing on the TSS effort.

Now we need to apply it to my #SUB10 race strategy at Challenge Almere-Amsterdam and check if the numbers are matching my nutrition and hydration expectations :

• 3.8K Swim = 0.55 kJ x 65.5 x 73 = 2,629 kJ
• 180K Bike = (18,360 x 190)/1,000 = 3,488 kJ
• 42K Run = (12,300 x 236)/1,000 = 2,903 kJ

That gives a total of 9019 kJ that should be partially replaced to avoid getting into the bad spot and being up for a solid bonking. I wrote partially because the cool thing here is that if you had a solid breakfast as we discussed earlier, your muscles and liver should already have some spare stock. It's individual — again — but you should start with the equivalent of 2,100 kJ ready to be used before you draw on your fatty acids to keep powering up your body, something we obviously want to avoid at all cost.

So let's grab the calculator again and finally compare it to my nutrition and hydration strategy :

• 14 gels x 418 kJ = 5,852 kJ
• 10 electrolyte drink x 272 kJ = 2,720 kJ

This brings us to a total of 8,572 kJ so pretty close in terms of raw deficit to the 9019 kJ of the total race effort, but positive if you take into account that I started the day with a stock of 2100 kJ in my body system thanks to a good carb loading and breakfast ! That calculation method is a broad picture, and you need to make sure that it's fitting well either in terms of timing or course — pro tips coming in the race chapter — but you get the message through this longest chapter of the blog : nutrition is the fourth discipline in long endurance triathlon, and if you're not willing to put in the necessary effort to get it right, you will not be able to complete the swim, bike and run at your best level, and achieve your dreams.