IRONMAN 70.3® World Championships

Consuming a varied intake of both ‘slow release’ starch and rapidly absorbed glucose:fructose carb sources, Matthew averaged an impressive carb intake this race, peaking at ~145g/h on the bike, before dropping down to ~110g/h while running. He was able to tolerate a very similar intake to this (~120g/h) at the full IRONMAN® World Championships in the extreme conditions of Kona just two weeks prior, again with no GI distress. This is a prime example of an athlete benefiting from gut training to allow for higher carb intakes, and practicing his strategy over and over again in training to prepare his stomach to handle it well on race day.

Matthew didn’t preload with a strong electrolyte drink like PH 1500. Given the performance enhancing benefits associated with inducing a small amount of hypervolemia (i.e. water retention), we’d recommend he uses this strategy ahead of his next race to ensure he’s starting optimally hydrated. During this race, he planned to follow a similar hydration strategy to his performance in Kona, although the weather conditions this time were approximately ~22°C / 72°F colder. The difference in environmental conditions was reflected in his reduced sweat rate, meaning his average fluid intake dropped by ~16%, from ~1.16L (39oz) per hour in Hawaii to ~972ml per hour in Utah, without experiencing any hydration related issues. Matthew did have some cramping when transitioning from the bike to the run, but it’s unlikely due to hydration because of his appropriate intake and mild weather. It’s more likely to have occurred due to one of the many other factors known to cause cramp, such as accumulated muscle fatigue.