I enable endurance athletes to overcome lack of energy and gut upset so that they can fuel their bodies with confidence and race to their full potential. Subscribe to my weekly 'Fuelling with Purpose' newsletter to receive endurance nutrition insights directly in your inbox.
Fuelling With Purpose — 30 September 2025
💡 Fuel For ThoughtGut Training: The Workout Most Runners Skip“Do not try anything new on race day” seems to be a well-known rule. However, when it comes to nutrition, many athletes interpret this too narrowly. They’ll test a gel once or twice in training, have no stomach upset, and assume they’re good to go. But tolerating one gel during an easy long run is not the same as fuelling with multiple gels per hour at race intensity. Your gut is trainable, just like your legs and lungs. Research shows that repeated exposure to carbohydrate during training can increase the gut’s ability to absorb and tolerate higher amounts. Meaning fewer GI issues and more energy when you need it most. Think of it like rehearsing for a play: you wouldn’t just read your lines once and hope it goes well on stage. You’d practice until the timing, delivery, and flow felt automatic. Race fuelling works the same way. So instead of just “checking the box” with a single trial gel, build gut training into your preparation. Practice your planned carb intake at your goal race pace, increase gradually toward your target grams per hour, and give your gut time to adapt. This way, your fuelling strategy is part of your training and not a gamble, and you fuel your training with the calories your body needs to adapt and grow stronger as a bonus. 🚀 Endurance Highlights1️⃣ Performance effects of caffeine accross different dietsCaffeine is well-documented as a performance enhancer, but does the athlete’s diet change how effective it is? This new study tested elite race walkers during a 3-week training camp where one group followed a high-carbohydrate diet and another a low-carbohydrate, high-fat ketogenic diet. On some sessions, athletes also consumed caffeine (3 mg/kg via caffeinated gum) before a 14 km hill workout. The findings showed that caffeine improved performance across the board: athletes completed the session 2–3% faster and had sharper cognitive performance, regardless of diet. However, diet still mattered. The high-carb group consistently trained at higher speeds and improved over time, while the keto group remained slower despite caffeine use. In other words, caffeine can partially rescue performance when carbs are lacking, but it cannot fully replace the benefits of training with high carbohydrate availability. 2️⃣ Maurten bicarb system: First look in endurance testingSodium bicarbonate has long been studied as a supplement to help power and sprint-based sports. Recently, the endurance world has started to explore its potential benefits, with Maurten developing the Bicarb System specifically for runners and endurance athletes. This study tested the product in eight collegiate distance runners, who completed treadmill intervals just above their lactate threshold on two occasions: once with the Bicarb System and once without. The results showed no significant differences in performance markers such as heart rate, blood lactate, perceived exertion, or respiratory exchange ratio between the two trials. However, an important finding was that athletes did not experience the gastrointestinal distress that is common with traditional sodium bicarbonate supplementation. While this small study suggests the Maurten Bicarb System may not deliver measurable performance gains in this context, it highlights a promising step toward making bicarbonate supplementation tolerable for endurance athletes. More research is needed to determine its effectiveness under different conditions, intensities, or race scenarios. 🕵🏻♀️ Retail Finds*This week's product review: Fixx Gel X ProI'm trying to keep up with the energy gels in the market but it's proving difficult. Here are my thoughts on Fixx's. Features & benefits
Things to keep in mind
Final take This energy gel is similar to many others in the market. If you like something more liquid with a bit of flavour you may enjoy this one. 👩🏻🍳 Kitchen CreationsI'm committing to sending the most valuable endurance nutrition newsletter. I want to make sure that every piece of content you receive has information that is helpful for you and your journey to achieving your personal best. Happy fuelling! Gaby | Endurance Nutrition Specialist p.s. Perth runners, let’s talk fuelling! Grab your free spot for my in-person masterclass this Saturday. Register here |
Gaby Villa
I enable endurance athletes to overcome lack of energy and gut upset so that they can fuel their bodies with confidence and race to their full potential. Subscribe to my weekly 'Fuelling with Purpose' newsletter to receive endurance nutrition insights directly in your inbox.
💡 Fuel For Thought From weight loss to performance gains: My conversation with Jimmy Runs A couple of weeks ago, I sat down with runner and YouTuber Jimmy Runs to unpack his current diet and dive into a topic so many endurance athletes wrestle with: the belief that getting lighter automatically means getting faster. Jimmy is chasing a 2:34 marathon and, like many driven athletes, believed that dropping weight was a key piece of the process. What unfolded in our conversation was a deeper look...
💡 Fuel For Thought You don't need podium goals to take your fuelling seriously I’ve seen so many runners quietly carry this belief: “I’m not fast enough to take my nutrition seriously.” Maybe you’ve felt it too, that little voice saying only podium-chasers get to focus on fuelling, while the rest of us should just “tough it out” and be grateful to finish. But nutrition isn’t a luxury reserved for the “serious” athlete; it’s the foundation that helps every runner enjoy the sport more. Think...
💡 Fuel For Thought Your fuelling strategy isn't a brand name When I ask athletes about their race-day nutrition strategy, many answer with a brand name: “I used X gels,” or “I tried X drink.” Unfortunately, products aren’t strategies. And when it comes to ultra-endurance, no single gel, bar, or bottle can cover everything your body needs over hours (or days) on your feet. That’s why so many nutrition plans fall apart, not because you picked the “wrong” product, but because you were relying on...