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Floris Gierman's scorecard

Chicago Marathon

Sunday 9th October, 2022

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 94g

    Carb per hour
  • 262mg

    Sodium per hour
  • 209ml

    Fluid per hour
  • 1,250mg/L

    Relative sodium concentration
  • 400mg

    Total caffeine
  • How Floris hit those numbers

    3 x Boiled Eggs
    0.5 x Cup of Black Beans (~16g carb)
    1 x Cup of Coffee with Heavy Cream (~15g Carb)
    300ml x Electrolyte Drink
    1 x PF 30 Energy Gel
    3 x PH Electrolyte Capsule
    4 x PF 30 Energy Gel
    4 x PF 30 Caffeine Gel
    600ml x Plain water

    How Floris' hydration and fueling went...

      • 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


      • 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


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Floris ensured that he had maximal energy availability on race day by carb loading in the days prior, culminating with a carbohydrate-rich dinner the night before. Carb loading contributes to glycogen stores in his muscles and liver, which are utilised to provide energy for muscle contraction during exercise
      • He also boosted his blood glucose with carbohydrates in his breakfast, and a final PF 30 Gel ~15 minutes out from the start. This elevated blood glucose at the startline can contribute to sparing of stored energy, meaning he had more left ‘in the tank’ for later in the race
      • While on the course, Floris got his fuel from PF 30 Gels which he consumed every 25 minutes to start with. He later started using PF 30 Caffeine Gels which he alternated with non-caffeinated versions every 20 minutes. This resulted in him having eight gels in total on the day, which is higher than his intake has been previously
      • He was inspired to increase his carbohydrate intake for this race after speaking to UTMB winner Kilian Journet on this podcast. Undoubtedly, along with the energy boost he felt from running in front of a great crowd, his consistent carb intake will have contributed to his perceived energy levels being so high (10 out of 10), especially in the latter stages of the run
      • Despite his training volume for this race “not being that high” by his standards, peaking at around 55-60 miles per week, and including some pickleball sessions with the family, Floris was able to run through the halfway mark at 1:27:30 and run a ‘negative split’ to the finish - even clocking a 6:15 minute mile right at the end of the race!
      • On average, Floris had ~94g of carb per hour through this race, which is just over the Fuel & Hydration Planner’s 90g/h recommendation for an event of this length and intensity. This is another example of an athlete consuming more than 90g carb per hour, which was previously thought to be a ceiling value. Happily, using PF 30 Gels, he was also able to report no GI distress on the day
      • In part, the high perceived energy and mental alertness Floris experienced would have been due to the effects of caffeine, which he consumed ~400mg of during the race. This would put someone of his size at the very top end of the general 3-6mg per kilo of body weight recommendation


      • 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”

    Key info

    Floris Gierman



    Overall Time

    Event information

    Chicago Marathon
    Chicago, United States
    9th October, 2022
    Total Distance
    42.2km / 26.2mi
    Total Elevation
    74m / 243ft

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    11°C / 52°F
    Max Temp
    17°C / 63°F
    Avg Temp
    15°C / 59°F

    Athlete feedback

    Race Satisfaction
    Energy levels
    Toilet stops
    GI comfort
    No cramping

    Floris' Thoughts

     My aim was to finish strong and healthy after some health challenges in the early stages of the training cycle, so this race felt great!

    Floris' full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake2707506004001,250
    Per hour94262209140

    Data Confidence







    There is an adequate level of accuracy in the data collected and the numbers reported. The athlete manages to recall what they ate and drank including most specifics (brands flavours quantities plausible estimations of volumes). However there are estimations made within the data which affect the overall confidence level in the data reported.

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