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Daniel Silvester's scorecard

London Marathon

Sunday 3rd October, 2021

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 63g

    Carb per hour
  • 349mg

    Sodium per hour
  • 366ml

    Fluid per hour
  • 952mg/L

    Relative sodium concentration
  • 0mg

    Total caffeine
  • How Daniel hit those numbers

    500ml x PH 1500 (Tablet)
    1 x Bagel with marmite
    1 x Bowl of porridge with syrup
    1 x Cappuccino
    1 x PF 30 Gel
    4 x PH Electrolyte Capsule
    5 x PF 30 Gel
    1.05L x Plain water

    How Daniel's hydration and fueling went...

      • After receiving some advice from our very own Sweat Expert James Phillips, Dan went into the Loch Ness Marathon with an excellent plan and kitted up with lots of PH products. Dan said ‘the advice was spot on and kept me going until the end’
      • Overall, Dan had an excellent marathon performance finishing in a time of 2 hours 52 minutes (a 22 minute PB!). He was aiming for under 3 hours and was delighted with his time saying that ‘to get 2:52:46 was like dreamland’
      • Dan rated his race satisfaction as 9 out of 10 because although ‘I would have bitten your hand off if you had offered me that time beforehand’, he believes there is still room for improvement in terms of ‘nutrition, being free from niggles and prepping with a few long runs’


      • Dan consumed around ~366ml/hr (~13oz/hr) fluid during the marathon which was ~1.05L/36oz of water in total. This was made up of drinking ~150ml plain water at each aid station which is a decent amount within what we would expect to see for these mild conditions
      • Although ~366ml/hr (~13oz/hr) will have replaced part of what he was losing, this quantity could have been higher. However, he mentioned he didn’t want to stop to pee therefore didn’t push his fluid intake
      • In terms of sodium, Dan had planned to take two PH Electrolyte Capsules for every 500ml/16oz of fluid he drank. However, Dan forgot to take the capsules until around 2 hours in. At this point he took three on board and then one half an hour later. Ideally he would have stuck to his plan to consume sodium throughout the race as he was losing it in his sweat, instead of playing catch up on sodium losses in the second half of the race
      • Considering our Online Sweat Test portrayed Dan as a high salty sweater, then replacing his sweat losses will have been important and may have played a bigger part in longer hotter races. He did not cramp but did say that in the middle of the race he experienced a really hard section where his ‘niggle felt worse’ and his ‘mindset was low’ and believed this could be down to neglecting the salt tablets up to that point


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Dan’s pre-race intake was solid; having a breakfast high in carbs and low in fibre and consuming a PF 30 Gel (as recommended by the Quick Carb Calculator) will have topped up his fuel stores before the race start of 10am
      • Dan had an excellent intake pushing the top end of the Quick Carb Calculator’s recommended range for a race of this length, to consume ~63g/hr throughout, solely from PF 30 Gels; using his pre-planned strategy of taking a PF 30 Gel every 30 minutes. Anecdotal evidence suggests that a higher carb intake can have greater performance benefits. Therefore pushing the top end of this range is excellent especially while being able to maintain GI comfort
      • Dan had tested using PF 30 Energy Gels a week before the race where he set a half marathon PB! As a result he felt confident using them here and had no issues. He rated his energy levels as 7-8 and said that the flat middle of the race and the last 2km were the hardest parts for him
      • Using his plan and the advice from James, Dan said his ‘fuelling was better than I have ever done before so I felt good’. He does believe that he could have perhaps consumed more around the middle and towards the end. If he is able to achieve higher intake while experiencing no GI issues then this could benefit his performance


      • Dan had a solid performance at the Loch Ness Marathon on the 3rd October. Sticking pretty closely to a planned hydration and fuelling strategy, Dan hit good numbers throughout to get a 22 minute marathon PB!
      • After first using PF 30 Gels in the run up to the race, he felt confident and used them effectively throughout to achieve a great carb intake. He did forget to take his planned PH Electrolyte Capsules until the second half of the race so in future races this is definitely important to remember considering our Online Sweat Test classified him as a salty sweater and he believes this could be linked to him struggling in the middle of the race

    Key info

    Daniel Silvester



    Overall Time

    Event information

    London Marathon
    London, England
    3rd October, 2021
    Total Distance
    42.2km / 26.2mi

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    12°C / 54°F
    Max Temp
    16°C / 61°F
    Avg Temp
    15°C / 59°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    Energy levels
    The middle of the race which was flat was actually one the hardest parts
    Toilet stops
    I had the feeling of needing to pee from about 6km but did not want to stop so just kept going
    GI comfort
    No cramping

    Daniel's Thoughts

     To get 2:52:46 was like dreamland. I think there is room for improvement (better dialled in to nutrition, free from niggles and a few long runs which I wasn’t able to do because of niggles) which is exciting but I would have bitten your hand off if you had offered me that time beforehand

    Daniel's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake1801,0001,0500952
    Per hour633493660

    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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