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James Phillips' scorecard

Mad Hatter Roseland Swimrun

Saturday 16th July, 2022

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 68g

    Carb per hour
  • 524mg

    Sodium per hour
  • 381ml

    Fluid per hour
  • 1,375mg/L

    Relative sodium concentration
  • 200mg

    Total caffeine
  • How James hit those numbers

    500ml x PH 1500 (Tablet)
    1 x Banana
    1 x Bowl of Overnight Oats
    250ml x Black Coffee
    2 x Spoonfuls of Greek Yoghurt
    500ml x PH 500 (Tablets)
    1L x PH 1000 (Tablets)
    6 x PH Electrolyte Capsule
    3 x PF 30 Gel
    2 x PF 90 Gel
    2 x PF 30 Caffeine Gel
    500ml x Plain water
    4 x Jelly Babies

    How James' hydration and fueling went...

      • Precision Fuel & Hydration’s Head of Athlete Support, James AKA “JP” and his swimrun partner Ant won the second edition of the 2022 Mad Hatter Swimrun series, this time the Roseland in Cornwall.
      • Having finished on the top step of the podium at the Hokey Cokey Swimrun also run by Mad Hatter earlier this summer, James and Ant were using Roseland as a “test-run” for their A-race of the season - the upcoming ÖTILLÖ Swimrun World Championships
      • Due to the increasing prevailing wind along the Cornish coast, the final two swim sections were cancelled and replaced with extra running. With this adjustment, the pair ended up swimming a total of 6km and running 30km, but managed to adapt their fuel and hydration plan accordingly


      • James’s sweat sodium concentration falls in the ‘very high’ category at 1,850mg/L, and he knows all too well how poor hydration can affect him when racing in the heat, having suffered with painful cramps and nausea in the past
      • With this in mind, JP preloaded the night before and the morning of the race to optimally top up his sodium levels and increase his blood plasma volume, thus reducing the load on his cardiovascular system
      • With PH 1000 being available at the on-course aid stations, it was easier for JP to meet his sodium and fluid needs. In total, he drank ~2L/64oz of fluid throughout the race by regularly filling up his soft flask at aid stations which he carried with him throughout the race. He also took six Electrolyte Capsules with him to top up his sodium intake whilst drinking plain water
      • This gave JP an average fluid intake of ~381ml/13oz per hour, which is much less than we’d recommend for someone with a sweat rate as high as him (~2L/64oz per hour in hot conditions)
      • Given the logistics of a swimrun event, where aid station fluids are the only opportunity to drink, James did a decent job of drinking when he could. He rated his hydration strategy 6 (out of 10) and said “I should have had more to drink, but my intake wasn’t structured enough to keep track of on-the-go”
      • JP’s sodium intake totalled ~2,750mg, which equates to ~524mg/h, and gave him a relative sodium concentration of ~1,375mg/L. This is a decent concentration of electrolytes to have consumed over a ~5 hour race, and would have replaced an adequate proportion of his sweat sodium losses
      • Achieving this relative sodium concentration with a greater hourly fluid intake would have ensured JP replaced a larger proportion of his losses, and could have reduced the likelihood of experiencing “semi-cramps” in his feet during the swim sections
      • The field James faced at Roseland was slightly lower than he will be up against at the World Championships, and therefore he didn’t feel like he needed to push himself enough to justify a more aggressive fueling and hydration strategy, saying “perhaps if I was racing on the limit I’d have been more tuned into hitting a particular fluid/fuel strategy”


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Fueling a swimrun can be tricky, as everything you carry needs to withstand being bounced around on the run and then submerged in the sea on repeat for several hours
      • James managed to pick up most of his fuel at the on-course aid stations which were stocking PF&H products
      • In total, JP took ~357g of carbs across the 5 hours 15 minutes, averaging ~68g/h. This is a decent amount of fuel, and is ~22g/h more than his previous Swimrun case study at the 2019 ÖTILLÖ Swimrun World Championships
      • This quantity is within the 60-90g recommended carb intake for a race of this duration and intensity, and will have ensured he had plenty of energy available throughout the race
      • JP hit this quantity of carb by taking 2 x PF 90 Energy Gels, 3 x PF 30 Energy Gels and 4 x Jelly Babies. He also got a decent caffeine hit alongside his carb intake by having 2 x PF 30 Caffeine Gels
      • Relative to his bodyweight, JP averaged ~2.7mg/kg of caffeine, which falls just below the recommended quantity for optimal performance (3-6mg/kg body weight). Whilst an athletes’ caffeine intake is very individual, we know that JP is an avid caffeine consumer (drinking several cups of coffee a day) and thus, he may want to pack another PF 30 Caffeine Gel for future events to ensure he gets the most performance boost available
      • Rating his energy levels 9 (out of 10), James felt that in hindsight he could have fueled more in the latter stages, but wasn’t expecting the higher energy demands of running in the final portion of the race after the swims were cancelled


      • James and his swimrun partner, Ant, had a “fairly good day” at the Mad Hatter Roseland Swimrun, taking the win and rating their race satisfaction 7 out of 10
      • The regular navigational mishaps during the race meant his “competitive instinct” was diminished as the race went on, and he felt his fueling and hydration strategy reflected that
      • Ahead of the 2022 ÖTILLÖ Swimrun World Championships in September, James should be looking to dial in his strategy and hit a slightly higher fluid intake, and perhaps consider bumping up his carb intake towards the upper end of the 60-90g recommendations

    Key info

    James Phillips

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


    Overall Time

    Event information

    Mad Hatter Roseland Swimrun
    Porthscatho, England
    16th July, 2022
    Swim Distance
    6.0km / 3.7mi
    Run Distance
    30.0km / 18.6mi
    Total Distance
    36.0km / 22.4mi
    Total Elevation
    1,400m / 4,593ft

    Event conditions

    Weather Conditions
    No Rain
    Min Temp
    15°C / 59°F
    Max Temp
    22°C / 72°F
    Avg Temp
    18°C / 64°F

    Athlete feedback

    Event Satisfaction
    Hydration rating
    Should have drank more, my intake wasn't structured enough
    Energy levels
    Toilet stops
    GI comfort
    Twinges but not full-on cramps

    James' Thoughts

     Really happy with my carb numbers, especially considering the last-minute course change and self-sufficient nature of the race

    James' full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake3572,7502,0002001,375
    Per hour6852438138

    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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