IAU 100km World Championships

James fueled his race with a combination of PF 30 Gels, PF 30 Caffeine Gels, and PF Carb & Electrolyte Drink Mix, achieving an impressive average carbohydrate intake. Emerging research continues to highlight the performance benefits of high carbohydrate consumption during exercise, primarily through increased exogenous carbohydrate oxidation. In simple terms, consuming more than 90g of carb per hour allows the body to utilise these external carbohydrates for energy. Although James reported no GI symptoms across the race, he did report that he struggled to take gels on at times. With the hot conditions reducing available blood supply to the gut, high carb intake and the high relative sodium concentration of his drinks, it’s possible that intake of ~111g per hour was as much as he could handle in those conditions. For future races, James could consider trialling a slightly lower carb and sodium intake to reduce the pressure on his gut during hot races.

Given the hot conditions, James knew the importance of managing his fluid and electrolyte losses effectively. The majority of his sodium intake came from 3 litres of PF Carb & Electrolyte Drink Mix and 12 Electrolyte Capsules, which provided a sodium concentration of ~1,858mg/L - significantly higher than the 757mg/L he loses in his sweat. Fortunately, this didn’t cause any negative GI symptoms. This strategy worked well for James on the day, but in future, James could consider decoupling his carb and electrolyte intake to give him greater control over his fluid, sodium, and carb consumption, and pull each lever independently based on his needs.

James is no stranger to using caffeine during races and consumed a dose well above the standard scientific recommendation of 3-6mg/kg. While such high doses can often lead to negative side-effects including stomach discomfort for some athletes, James tolerated it well and likely benefited from the stimulant's ergogenic effects. Moving forward, he might consider slightly reducing his caffeine intake to align more closely with the recommended range, but if his current approach continues to work without drawbacks, there may be little need to change.