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Francois de Repentigny's scorecard

Boston Marathon

Monday 11th October, 2021

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 51g

    Carb per hour
  • 380mg

    Sodium per hour
  • 350ml

    Fluid per hour
  • 1,085mg/L

    Relative sodium concentration
  • 2.11mg/kg

    Caffeine per bodyweight
  • How Francois hit those numbers

    500ml x PH 1000 (Tablet)
    1/3rd x Overstim energy cake
    1 x Coffee strip
    1 x Energy gel (22g carb)
    5 x PH Electrolyte Capsule
    5 x PF 30 Gel
    1.5L x Plain water
    2 x Energy gel with caffeine (22g carb, 75mg caffeine)
    20ml x Electrolyte shot (556mg sodium)

    How Francois' hydration and fueling went...

      • Francois, a PH customer, had a 20 minute call with one of our Sweat Experts to refine his hydration and fueling strategy before the Boston marathon (book a free 20 minute call to discuss your strategy here). After a detailed chat about how to adjust his usual plan to the slightly cooler conditions Francois felt confident in his plan going into the marathon
      • Unfortunately for Francois, the race did not go as planned due to an injury to his hip adductors. Originally aiming for a time of 3 hours 25 minutes, he soon realised that this was not going to be and just finishing the race would be an achievement. Pushing through the pain, he successfully crossed the finish line in 4 hours 17 minutes
      • Despite ‘blowing up’, Francois was happy with his hydration and nutrition plan which he stuck to throughout. One big challenge for him was trying to adjust to the extra hour in duration due to the injury


      • Francois consumed around ~350ml/hr (~12oz/hr) fluid during the marathon by drinking around ~50ml/2oz at every aid station and also carrying a 250ml/9oz flask. This fluid intake will have replaced a proportion of the fluid he will have been losing, but the temperature got higher than predicted and he was racing for longer than planned, therefore he was sweating more for longer. Despite not knowing Francois’ sweat rate, we would, as a result, recommend a higher overall fluid intake (closer to ~500ml/16oz per hour if this was tolerable with no bloating or sloshing)
      • He did not pee during the race and said that afterwards his pee was dark. This does suggest slight dehydration which matches our recommendation that his in race fluid could have been higher
      • In terms of sodium, Francois took five PH Electrolyte Capsules during the run and an electrolyte shot after mile 21. In relation to the fluid he was consuming, the relative sodium concentration of Francois’ intake was ~1,085mg/L. This is similar to his sweat sodium losses of 1,024mg/L, therefore replacing a good proportion of the sodium he was losing in his sweat
      • Francois did start to feel twinges of cramp after mile 21 and had taken all of his PH Electrolyte Capsules so took an electrolyte shot containing a large amount (556mg) of sodium. He reported this helped him and he did not experience full-on cramps. It is not unusual in the later stages of an endurance event for a salt capsule to stave off twinges of cramp turning into full-blown cramping however it should be noted that this isn’t a guaranteed ‘fix’, nor may it last the remainder of the race, as fundamentally dehydration is often the main underlying problem which needs addressing


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Francois had a solid pre-race intake. He consumed a breakfast high in carbs and meeting the recommendations of the Quick Carb Calculator, he consumed 30g of carb in the form of an energy gel in the final 30 minutes before the race. This will have topped off his fuel stores well before the run
      • During the marathon, Francois consumed five PF30 Energy Gels along with a couple of caffeinated energy gels to reach a carb intake of ~51 grams per hour. Pushing towards 60g/hr is a decent amount to fuel his effort
      • Ideally, due to the duration he was racing pushing over 60g/hr would have been desired to aid performance. However, considering the length of the race was longer than anticipated, Francois luckily had a couple of extra gels on him and did well to adjust and keep his intake up
      • Unfortunately, Francois reported low energy levels (3/10) but said this was down to his ‘mechanical problem’ not his nutrition. Considering he was consuming ~51g/hr, we agree that his low energy was probably not a result of his carb intake
      • Consuming ~150mg caffeine in total, equating to ~2.12mg per kilogram of body weight (mg/kg BW), is just below the recommended caffeine range for performance (3-6 mg/kg BW) but Francois did also have a coffee strip pre-race. Overall, he therefore had a moderate dose of caffeine, which he is accustomed to, to aid performance


      • Considering Francois' plan was made for the duration of three and a half hours his intake numbers were decent but could have been higher in terms of carbs, sodium and fluid. He made the adjustments he could by having a couple of extra gels but picking up extra fluid could be something to think more about in the future, especially when the conditions are warm
      • With his painful injury, it was a huge success for him to finish the race (well done Francois!) and his hydration and nutrition plan although prepared for a shorter race fueled him well

    Key info

    Francois de Repentigny



    Overall Time

    Event information

    Boston Marathon
    Boston, USA
    11th October, 2021
    Total Distance
    42.2km / 26.2mi

    Race conditions

    Weather Conditions
    Hot and Humid
    No Rain
    Min Temp
    17°C / 63°F
    Max Temp
    21°C / 70°F
    Avg Temp
    19°C / 66°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    Energy levels
    Low energy levels but due to my injury not nutrition related
    Toilet stops
    GI comfort
    No cramping

    Francois' full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake2161,6291,5011501,085
    Per hour5138035035

    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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