• Floris is the co-founder of Path Projects and hosts the Extramilest performance podcast. He recently ran his third ‘majors’ race by completing the Chicago Marathon on a mild day (15°C/59°F and minimal wind) which he described as “perfect weather for running a fast race”
• With an all-time personal best of 2:44 at the Boston Marathon eight years prior, he approached this race with the simple aim of finishing “strong and healthy”, which he happily did by setting a new ‘masters age category’ PB of 2:52:32

Hydration

• As a seasoned endurance athlete, Floris knew that he should aim to start his race hydrated, and so drank ~300ml of electrolyte drink the morning of the event. To optimise this strategy, we’d suggest having a stronger electrolyte like PH 1500 both the evening before and the morning of the race to boost blood plasma volume
• After making use of the elite bathrooms ~15 minutes before the gun went off, Floris toed the line and set off with over 40,000 other competitors to run the streets of Chicago
• Floris utilised 10 of the aid stations which were fairly spread throughout the marathon by picking up cups of water and having two sips at each
• This meant that he had an overall fluid intake of ~600ml, which averaged out at ~209ml per hour. On this occasion, given the temperate conditions and Floris’s own perceptions of his fluid losses throughout the race, it's likely that this volume was appropriate, but it’s something we’d definitely see increase if Floris competed in a warmer race in future
• Floris cleverly taped single Electrolyte Capsules to his PF 30 Gels so that he wouldn’t have to fumble around in his pockets to access them. By taking three capsules he was able to maintain a relative sodium concentration of ~1,250mg/L (mg/32oz) for the race
• We don’t know Floris’s exact sweat sodium concentration as he hasn’t had a Sweat Test yet. However, given Floris didn’t report any hydration-related issues during the race and he doesn't perceive his sodium losses to be on the higher end of the scale, it’s safe to assume that his race intake would have replaced a solid proportion of his losses

Fueling

Conclusions

• Floris did extremely well to execute a solid fuel and hydration strategy for the Chicago Marathon. In part, it will have contributed to his high reported energy levels and reports of no cramping
• This race undoubtedly ticked all the boxes Floris wanted it to, with the aim of finishing “strong and healthy”, he did just that and enjoyed what he described as his “most fun race day experience ever”