IRONMAN® World Championship

Jenny executed one of her strongest fueling strategies to date, averaging ~101g of carbohydrate per hour on the bike and ~65g/h on the run, resulting in a total intake of just over one kilogram of carbs across nearly 14 hours of racing. Despite the significantly hotter and more humid conditions in Kona compared to her previous race at IRONMAN® Leeds, Jenny successfully increased her overall carb intake through a couple of refinements to her pre-race and run strategy, including using a mixture of PF 300 Flow Gel, PF Chews and PF 30 Caffeine Gels. This increase is particularly impressive given that heat stress can often reduce gut tolerance due to blood flow being redirected to the skin for cooling, but given Jenny's dedicated heat prep it was reassuring to see it paid off. Jenny reported no major dips in energy throughout the day, demonstrating that her fueling plan effectively sustained her performance from start to finish. Continuing to work on her carb intake to push towards an average of 90g/h through more gut training, especially now she has a solid nutrition plan in place, will help her further increase what she can tolerate and better support her performance.

With a sweat sodium concentration of 1064mg/L, Jenny needs to be conscious of her sodium replacement, particularly in hot, humid conditions like the World Championships in Hawaii where conditions are known to be brutal. She relied on pre-made bottles (on the bike) and soft flasks (on the run) of PH 1500, starting with a set and then collecting another round at personal needs. Combining this with the plain water she picked up from aid stations on both the bike and run, Jenny averaged ~700ml of fluid per hour, enough to avoid suffering from any detrimental levels of dehydration.

This was supported by measures of pre and post body mass, showing Jenny finished only 1.3% down, which sits within the ideal range for hydration status at the finish line. Two improvement opportunities would have been to use PH 1500 in the final hours before the race start rather than PH 1000, to help maximise fluid retention and start optimally hydrated, along with using 2 x packets of PH 1500 in her starting litre bottles or bringing along some Electrolyte Capsules.

Jenny’s caffeine intake sat just slightly above the general recommended range for endurance performance. As someone who frequently consumes caffeine through coffee and tea, Jenny knew she could tolerate this intake and it suited her well during the race. She dosed caffeine strategically throughout the day, starting with a PF 30 Caffeine Gel just before the swim, another three on the bike and then one on the run. This helped maintain perceived energy and focus in the latter stages of the race when mental fatigue and rising perceived exertion from the heat could have been limiting factors in performance.