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Robbie Britton's scorecard

Anglo-Celtic Plate 50km

Sunday 3rd April, 2022

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 84g

    Carb per hour
  • 661mg

    Sodium per hour
  • 441ml

    Fluid per hour
  • 1,500mg/L

    Relative sodium concentration
  • 3.13mg/kg

    Caffeine per bodyweight
  • How Robbie hit those numbers

    500ml x PH 1500 (Tablet)
    2 x Slices of toast with jam
    1.5 x Mug of black coffee
    1.3L x PH 1500 (Drink Mix)
    7 x PF 30 Gel
    2 x Caffeine gum (100mg caffeine)

    How Robbie's hydration and fueling went...

      • Robbie laid down a dominant performance at the Anglo-Celtic Plate 50k and crossed the finish line more than 21 minutes ahead of second place. The North Norfolk Beach running club member was due to run the Milan marathon before a late change of plan led to him entering this tough ultra-marathon race at the very last minute and said his performance “couldn’t have been much better”. Proudly one of only three “accurately measured 50k races in the UK”, the 21-lap race saw Robbie catch the leader with just 12km to go, which makes his substantial winning margin even more impressive
      • Whilst Robbie didn’t completely execute his normal pre-race fueling strategy, he more than made up for this during the race and clearly fueled excellently to finish strong
      • Overall, Robbie said he felt “Pretty chuffed” with how his fuelling and hydration strategy played out


      • Robbie preloaded with 500ml/16oz of PH 1500 ~2 hours prior to the race start which ensured he began racing in an optimally hydrated state
      • During the race, Robbie made use of his personalized aid station each lap to ensure he consumed his PH 1500 frequently, managing to consume ~1.3L/44oz through regular, smaller doses across the whole race. This gave Robbie an average relative sodium concentration of 1,500mg/L, which is a solid consumption and will have gone a long way towards matching his total sodium losses. Robbie describes having a particularly high sweat rate and he knows from his Advanced Sweat Test that he has a moderate-to-high sweat sodium concentration (1044mg/L), but as the weather was fairly cold (~8℃) and windy, his fluid and sodium intake would likely have replenished his losses adequately
      • During the last hour of racing, Robbie’s fluid intake fell slightly from ~500ml/hr (16oz/hr) to ~300ml/hr (10oz/hr). At the same point he felt he had to slow his pace slightly in the last 3-4 miles as he was cautious to avoid muscle cramps in his hamstrings and calves. He attributed this to a lack of race-specific conditioning in the lead up to the race, not his fluid-electrolyte balance
      • Robbie was really pleased with his hydration strategy and said he wouldn’t have changed anything if he had to do the same race again


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Robbie was awake early before the 7am race start, having some toast with jam and a bowl of cereal with yogurt a little over 2 hours before the gun went off. This ensured his glycogen levels were optimal
      • In the final 30 minutes before the race Robbie usually has a PF30 gel, but this time he didn’t. Usually we recommend a “carb hit” in the last 30 minutes before an event to ensure energy availability is adequate from the gun
      • During the race, Robbie averaged an impressive ~105g/hr of carbs during the first 2 hours by consuming a PF30 gel every ~20 mins. This exceeds our recommendations (60-90g/hr) for a race of this length, and supports evidence suggesting a positive relationship between carbohydrate intake and performance enhancement. During the final hour, Robbie opted to skip one of his gel pick-ups and grab a drink instead, listening to his body’s desire for fluids, and collecting his gel on the following lap ~9 minutes later
      • During the last hour of the race, Robbie averaged ~39g/hr. This tapering of carbohydrate consumption isn’t uncommon in ultramarathon racing due to a plethora of reasons such as taste fatigue and forgetting to take gels. Robbie put it down to the fact that he missed a fueling opportunity at 2:20, which subsequently moved to the next lap (2:30) and this meant his next gel, scheduled for 2:40 felt too soon. In hindsight, he felt he should have taken the next gel regardless
      • Overall, Robbie averaged an impressive ~83g/hr during the whole race, and had no GI distress at all, which is testament to his prior gut training and familiarity with this type of aggressive race fuelling


      • Robbie said he was “pretty chuffed with the whole race execution” and as a last minute change of plan, it couldn’t have gone much better. His high-carb fueling strategy was excellent in the first two-thirds of the race and tailed off slightly towards the end, but caused no major issues for Robbie
      • In Robbie’s future ‘A’ races, he will dial in his training more specifically, therefore his risk of cramp-like muscle pains will likely be reduced

    Key info

    Robbie Britton

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


    Overall Time

    Event information

    Anglo-Celtic Plate 50km
    Perth, Scotland
    3rd April, 2022
    Total Distance
    50.0km / 31.1mi

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    5°C / 41°F
    Max Temp
    9°C / 48°F
    Avg Temp
    8°C / 46°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    I wouldn't change a thing
    Energy levels
    Toilet stops
    GI comfort
    No cramping

    Robbie's Thoughts

     Pretty chuffed with it

    Robbie's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake2491,9501,3002001,500
    Per hour8466144168

    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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