This week, Michael welcomes Jamie Pugh, co-founder of EXO Analytics and senior lecturer at Liverpool John Moores University. Jamie's research focuses on carbohydrate metabolism and the role of gut function during endurance exercise. The conversation explores the novel means that EXO Analytics brings lab-grade carbohydrate oxidation testing to athletes, the physiological insights behind carb intake, and the practical implications for fueling strategies in training and racing. Key Takeaways * What EXO Analytics Measures: EXO tests how much of the carbohydrate an athlete consumes during exercise is actually used by the muscles, using stable-isotope tracers and indirect calorimetry. * Why It Matters: Understanding exogenous carbohydrate oxidation helps athletes personalize fueling to avoid both under-fueling and gastrointestinal distress. * Individual Variation Is Wide: Even among trained athletes, optimal carbohydrate use ranges from about 60 to 120 grams per hour, with little correlation to performance level. * Gut Training & Adaptation: While athletes can improve tolerance to carbohydrate intake, current evidence doesn't confirm that "gut training" increases absorption efficiency—though it likely improves comfort and logistics. * Beyond the Lab: EXO's home-testing kit combines breath sampling and portable metabolic measurement, offering a simplified way for athletes to assess real-world fueling capacity. To learn more, visit exoanalytics.co.uk [https://exoanalytics.co.uk/] or follow Jamie on Instagram at @jamiepughperformance.