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Evan Scully's scorecard

Paris Marathon

Sunday 2nd April, 2023

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 111g

    Carb per hour
  • 88mg

    Sodium per hour
  • 91ml

    Fluid per hour
  • 962mg/L

    Relative sodium concentration
  • 200mg

    Total caffeine
  • How Evan hit those numbers

    400ml x PH1500 (1 x tablet)
    1 x Bagel with cream cheese and honey
    2.5 x Cups of Tea
    1 x Pot of rice pudding
    1 x PF 30 Energy Gel
    2 x PF 30 Energy Chews
    200ml x PF 60 Energy Drink Mix (1 scoop)
    5 x PF 30 Energy Gel
    2 x PF 30 Caffeine Gel
    60ml x Plain water

    How Evan's hydration and fueling went...

      • Evan is a Physical Therapist and Coach from Ireland who was diagnosed with Cystic Fibrosis (CF) at five months old. CF is assessed using the same gold-standard measurement that we use for our Sweat Test, as sufferers of the life long condition typically have very salty sweat, and identifying this at a young age is vital for effective treatment
      • When he was a child, Evan’s parents were told he’d be lucky to live past the age of ten. Now 36 years old, Evan has broken records for the fastest 5km and half marathon time as someone with CF
      • Averaging 4 minutes and 4 seconds per kilometre (6:32 per mile), Evan finished the Paris Marathon in 2:51:48, whilst consuming an impressive ~111g of carbohydrate per hour en route to claiming another PB & European record


      • Typically, people with Cystic Fibrosis like Evan lose a lot of sodium in their sweat, and so have to focus on nailing electrolyte replacement during endurance events like the marathon, as Evan knows all too well
      • A really positive recent development in the treatment of CF are drugs which reduce the extent of electrolyte excretion in the sweat, and so Evan has been able to adapt his hydration strategy (and specifically his sodium intake) accordingly in recent years
      • He started the day with the strong PH 1500 electrolyte drink in order to boost his blood plasma volume ahead of the race, enhancing his body's temperature regulation capability, and reducing cardiovascular strain
      • After this, he drank very little throughout the race, giving him an average intake of just ~91ml (3oz) of fluid per hour. Despite this, he reported being very happy with his hydration strategy on the day as he didn’t need to pee during the race, but it was still clear in colour when he went to the bathroom immediately afterwards
      • It’s likely that Evan required such little fluid during the race as his sweat losses were minimal in the cool Parisian climate (6ºC / 53ºF)


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • As a coach of more than 100 Olympic athletes, Evan knows the importance of fueling right for the demands of an event like the marathon. He approached the race by maximising his stored energy through carb loading
      • On the morning of the race, he topped off his blood glucose with two PF 30 Chews and a PF 30 Gel in the last 30 minutes ahead of the race start, in order to spare some of his stored energy for later in the race
      • This ‘pre-fueling’ strategy in the final 30 minutes pre-race, alongside his use of a PF30 Gel every 20 minutes throughout the race resulted in him averaging a very impressive ~111g of carb per hour
      • This is just above the Fuel & Hydration Planner’s general recommendation of 90g per hour, but gives more anecdotal evidence towards the fact that athletes can tolerate taking on more than this previously thought ‘ceiling’
      • We would normally only recommend a final boost of energy with 30g of carb ~15 minutes before the start, to reduce the risk of rebound hypoglycemia. Without his 90g intake included in the numbers, he would have averaged closer to ~78g per hour during the race
      • This high carb intake meant that Evan still felt energetic for the final five miles of the race, which are mostly uphill on this course!
      • Evan also took on 200mg of caffeine throughout the race, in the form of evenly spread out PF 30 Caffeine Gels. For someone of his bodyweight, this would likely fall at the lower end of the general 3-6mg per kilo recommendation. This means that there’s some room for optimisation here if he wanted to truly maximise the ergogenic effects associated with caffeine consumption


      • Evan was extremely satisfied with achieving an 18 minute personal best at the 2023 Paris Marathon. He was especially pleased to set the new CF European marathon record in the process
      • Appropriate fueling in the build up and throughout the race meant that Evan perceived his energy levels on the day a perfect 10 (out of 10)
      • Looking towards his next race, Evan may be able to optimise his strategy by pushing the caffeine intake slightly higher and reaping the associated benefits, and if temperatures are higher in future races, he may look to increase his fluid and sodium intake

    Key info

    Evan Scully



    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
    I didn't need to pee despite not drinking much during the race, and my pee was still clear afterwards.
    Energy levels
    GI comfort
    No cramping

    Evan's Thoughts

     I'm very happy with an 18 minute PB and Eurpoean record for fastest person with cystic fibrosis to do a marathon!

    Evan's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake315250260200962
    Per hour111889170

    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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