IRONMAN® Leeds 2025

Following his recent IRONMAN® races, where fueling proved to be his biggest challenge, Harry has been training his gut to tolerate higher carb intakes to support the high power and speed outputs required to be competitive in professional triathlon racing. His podium finish in Leeds came with his highest carb intake to date - evidence that GI issues can be overcome with consistent training and an individualised strategy. While the hilly nature of the bike course was challenging, it actually worked in Harry’s favour when it came to fueling. He felt he was able to drip-feed his carbs more effectively than previous, flatter races where constant high intensity riding in the aero position made this trickier. Harry should take real confidence from how he executed his fueling in this race; his focus now will be keeping it up for the IRONMAN® World Championships in Nice.

Harry’s fluid intake replaced a good proportion of his sweat losses, helping him stay within his body’s tolerable level of dehydration. The cramping he experienced on the bike could be attributed to his relative sodium concentration being ~389mg/L lower than his sweat sodium concentration. Harry responded quickly to the cramping by picking up two bottles of on-course PH 1000 (Tablets), enabling him to get back on top of his electrolyte balance, alleviate the symptoms and push hard through the final section of the ride. Harry started the run with a Flow Flask 120 filled with overconcentrated PH 1000 (Drink Mix), but once he finished it, he consumed only plain water for the rest of the marathon. Looking ahead, especially in hotter conditions, Harry would benefit from picking up additional electrolytes on the run to better maintain his fluid and electrolyte balance.

Caffeine is a common part of many endurance athletes’ fueling strategies due to its ergogenic effects; however, Harry struggles to tolerate it and has largely cut it out due to GI discomfort. He did not take on any significant sources of caffeine over this race, only cola from aid stations which provided regular but very small doses through the run. Harry is considering reintroducing PF 30 Caffeine Gels in training to see how he tolerates them, as including caffeine in his race plan may help to smooth out some of the peaks and troughs in energy that he felt during the marathon in Leeds.