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James Phillips' scorecard

Paris Marathon

Sunday 2nd April, 2023

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 83g

    Carb per hour
  • 573mg

    Sodium per hour
  • 237ml

    Fluid per hour
  • 2,419mg/L

    Relative sodium concentration
  • 2.78mg/kg

    Caffeine per bodyweight
  • How James hit those numbers

    500ml x PH 1000 (1.5 Tablets)
    3 x Slices of Toast with Jam
    2 x White Coffee
    1 x PF 30 Energy Chews
    500ml x PH 1000 (Three Tablets)
    1.33 x PF 90 Energy Gel
    2 x PF 30 Caffeine Gel
    120ml x Plain water

    How James' hydration and fueling went...

      • James (JP) is head of Athlete Support at PF&H, and was the first of five team members to complete a 2023 spring marathon in his debut over the distance
      • Thankfully, his years of racing endurance sports, and expertise in fuel & hydration meant he had a dialled nutrition strategy, which he executed perfectly to run an impressive 2:37:14, setting a tough benchmark for the rest of the team to aim for


      • James unfortunately forgot his tube of PH 1500s when leaving the UK and heading to France for this race (something we won’t let him forget in a hurry). Thankfully, he knew the relative sodium concentration of his preloading drink was the most important factor, and used 1.5 x PH 1000 Tablets in 500ml (16oz) to achieve the 1,500mg per litre concentration
      • Then during the race he carried a Soft Flask loaded with three PH 1000 Tablets, and planned to drink some plain water from the aid stations to effectively dilute this concentration. James didn’t manage to pick up as much water as he’d planned, partly because temperatures were so low, he just wasn’t thirsty, nor was he sweating a huge amount
      • In total, he consumed ~620ml of fluid throughout the race with a relative sodium concentration of ~2,419mg/L (mg/32oz). This is a very high concentration, and although JP is at the top end of our ‘salty sweaters’ list, with a sweat sodium concentration of 1,850mg/L, he could perhaps have drank a little more water, or included less electrolyte to reduce this concentration somewhat
      • After the race he felt quite thirsty, which could be due to the high amount of sodium in his drinks. Thankfully he didn’t experience any GI issues, and only experienced some minor cramp in his calf at ~37k, which he felt was due to increasing his pace slightly, and a small section of running on cobblestones which offset his footing a little bit


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • JP is well versed in the realms of carbohydrate loading, and even co-wrote our blog post on how to carb load for your next race, so it was no surprise to see plenty of high-carb foods on he pre-race intake, finishing with some slices of toast and jam for breakfast on race morning
      • After tracking his glucose response with a continuous glucose monitor (CGM) from Supersapiens in his training, James was able to assess the optimal time frame for carbohydrate ingestion pre-race, and executed a perfect plan by taking a pack of PF 30 Chews within the last 20 minutes before the start
      • This peaked his blood glucose optimally (check out his glucose trace here), thus sparing his stored glycogen for later in the race when he really needed it
      • Also from his CGM testing, JP compared his glucose response between three sources of carbohydrates, the PF 30 Chews, PF 30 Gels and PF 60 Drink Mix. He decided to use Gels as his primary source for the race as he could maintain a stable glucose level, and they were the easiest source to consume whilst running at ~3:44 per kilometer (6 minute miles)!
      • He began the race with two PF 30 Caffeine Gels and two PF 90 Gels, but only got ~30g of carb out of the second Jumbo Gel before feeling a little full. He still managed to average ~83g of carb per hour, which is slightly lower than the 90g/h recommended by our Fuel & Hydration Planner, but he rated his energy levels 10 (out of 10), and managed to run his fastest 5k split in the final section of the race, indicating that he fueled well


      • In all, James executed a solid fuel and hydration plan, along with a sensible pacing strategy which allowed him to finish strong
      • After reflecting on the race, he feels he could possibly have a faster marathon in his legs, and is keen to scratch this itch at some point in the near future

    Key info

    James Phillips

    Sweat sodium concentration
    Sweat sodium classification
    Very High
    * determined by a PH Advanced Sweat Test


    Overall Time

    Event information

    Paris Marathon
    Paris, France
    2nd April, 2023
    Total Distance
    42.2km / 26.2mi
    Total Elevation
    269m / 883ft

    Race conditions

    Weather Conditions
    Min Temp
    6°C / 43°F
    Max Temp
    8°C / 46°F
    Avg Temp
    7°C / 45°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    If I did it again, I would carry a couple of Electrolyte Capsules and drink a bit more water
    Energy levels
    Toilet stops
    GI comfort
    Twinges but not full-on cramps

    James' Thoughts

     I raced with a "limiter" on so I didn't blow up, but as my last 5k was my fastest, I feel this has generated an itch I want to scratch at some point!

    James' full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake2161,5006202002,419
    Per hour8357323776

    Data Confidence







    There is good confidence in the accuracy of the data reported. An athlete feels that the numbers closely reflect what they consumed despite a couple of estimations which may carry some degree of error. The majority of what was consumed is recorded to a high level of specificity (most volumes are known through the use of bottles brands quantities flavours). The numbers are very plausible and align with previous data recordings (if an athlete has collected data previously).

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