Triathlon nutrition & fuelling

That moment, combined with other nutrition struggles during my 18-year professional career, is why I co-founded truefuels. My simple belief has always been the same: nutrition is the reason most things go wrong in endurance sport, and it shouldn’t be. truefuels exists to provide the nutrition solutions that you can trust for training and racing. I believe that nutrition should never be the thing that slows you down in a session, or ruins your race — and that is my goal. Our core brand principle is “only what you need.” That’s why we’ve avoided artificial flavours and limited preservatives.

We set out to build a fuelling system that reflects real human physiology, not marketing gimmicks. The truefuels fuelling system has three components — Gel, Electro and CoreCtrl. Designed to deliver maximum carbohydrate to your muscles, meaningful electrolytes that support absorption, and targeted thermoregulation support when heat becomes the limiter. Nothing more. Nothing you don’t need. All our products are designed to work together as part of our stackable system, so you can tailor your solution to be right for you.

Here’s the long-form guide I wish I’d had as a serious amateur triathlete chasing my first 70.3 or tackling my fifth Ironman.

The gut is trainable, just like your legs. During a build block, I fuel most long (over 60 minutes) and intense sessions with 80–120 g of carbohydrate per hour using the same truefuels Gel products I’ll use on race day. That repeated exposure “trains” your gut to better tolerate and more quickly absorb carbohydrates by up-regulating the transporters in your intestine. These transporters are proteins in the intestinal wall that act as channels, moving glucose (via SGLT1) and fructose (via GLUT5) from the gut into the bloodstream.

The more transporters you have, and the more active they become, the greater the number of carbohydrate molecules that can cross into the blood. This significantly reduces the risk of stomach problems and increases the rate at which your body processes and uses carbohydrates for fuel. Under-fuelling in training costs you more than you think. You blunt training adaptations, slow recovery, increase illness risk, and arrive at race week with a gut that’s never practised high intake.

Here are practical, evidence-based targets for serious amateurs. These are starting points. The single most important piece of advice for race nutrition: Practise it in training at least 5 times before the event.

My tip: I find that combining my nutrition into one bottle is the best way to make sure I get what I need when I need it. That's why you only have to sip from that bottle and pick up water on the course. For example, when I was racing T100 distance, I would have 6 High Salt Gels in one bottle on the bike (240g Carbs and 6g Salt for two hours), and 3 High Salt Gels in a squeezy bottle for the run. I knew that a sip would be approx 10g of carbs, so all I needed to do was have one sip every 15 minutes.

CoreCtrl is the third pillar of the truefuels system and introduces a completely new category: performance thermoregulation. In hot conditions, even perfect fuelling and hydration can only take you so far if your body can’t shed heat efficiently. CoreCtrl is designed to support your body’s natural cooling mechanisms by enhancing sweat gland activation, improving evaporative heat loss, and slowing internal heat storage. Its patent-pending formula combines a high dose of L-taurine with piperine for better absorption and a balanced electrolyte profile — all aligned with our “only what you need” philosophy.

You take one serving daily for 8 days before hot races or training blocks (mixed with 500 ml cold water, 30–60 minutes before exercise). Or, take it for two days on one day off if you weight under 60kg. It doesn’t replace hydration or pacing, but when used alongside truefuels Gel and Electro, it gives you the physiological edge to stay in control as temperatures rise and most athletes start to suffer.

I get asked all the time whether people should take it for an event in a few weeks, and the forecast calls for average conditions. If there is even a small chance the temperature could climb into the high teens or above, take it. There isn’t a downside, and the performance benefits are among the best I’ve ever seen in the scientific literature on exercise performance.

In my early long-distance triathlon races in 2018 and 2019, I was really struggling with nutrition. I kept getting it wrong, either taking in too little and fading, or suffering stomach problems that ruined the race. So I decided to design my own system. Working closely with a nutritionist and testing extensively in the lab, I realised two key things: removing all the unnecessary additives completely eliminated the GI problems, and making everything simple to ingest in race situations (everything in one bottle where possible) removed all the stress and decision-making under fatigue.

The truefuels system is a fully stackable approach, designed from the latest sports science and tested by me in training, racing, and the lab. It has also been refined by feedback from 100 real co-creators, dedicated athletes who have put the products through thousands of miles of real-world use. truefuels Gel: 40 g carbohydrate in a proven 1:1 glucose–fructose ratio + meaningful electrolytes (0.25 g or 1 g salt options, natural potassium from coconut, magnesium). Fluid texture, water-mixable, unflavoured base with minimal additives to reduce osmotic load and GI distress.

truefuels Electro: Precision electrolytes (400 mg sodium, natural potassium, magnesium) with light natural flavours. CoreCtrl: Supports your body’s natural thermoregulation in heat by enhancing sweat response and evaporative cooling. Taken for 8 days before hot races, it works alongside Gel and Electro.