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Rebecca Clarke's scorecard

IRONMAN European Championship

Sunday 2nd July, 2023

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 69g

    Carb per hour
  • 268mg

    Sodium per hour
  • 444ml

    Fluid per hour
  • 604mg/L

    Relative sodium concentration
  • 635mg

    Total caffeine
  • How Rebecca hit those numbers

    750ml x PH 1500
    2 x Gluten Free toast with peanut butter
    1 x Banana
    1 x PF 30 Gel
    *** Review technique if drinking much at this point!
    500ml x PH 1500 (Drink Mix)
    2 x PH Electrolyte Capsule
    500ml x PF Carb & Electrolyte Drink Mix (mixed to 1.5 x strength)
    2.5 x PF 30 Chews
    5 x PF 30 Gel
    3 x PF 30 Caffeine Gel
    1L x Plain water
    500ml x PH 1000 (Drink Mix)
    3 x PF 30 Caffeine Gel
    1 x PF 90 Gel
    1.08L x Plain water
    360ml x Cola

    How Rebecca's hydration and fueling went...

      • After a strong race at IRONMAN New Zealand last time out, Rebecca went into the European Championships in Frankfurt with high hopes of another good performance
      • She made some refinements to her fueling strategy to help feel stronger throughout, but Rebecca felt she ended up spending too long chasing her competitors without fueling correctly on the bike, resulting in a slight lack of energy heading onto the run
      • Despite struggling to fuel correctly on the bike, she attempted to catch up during the run, whilst maintaining an appropriate hydration strategy. This helped her secure an 8th place finish, which included an impressive 3:20 marathon


      • Rebecca implemented a very similar pre-race hydration strategy to IRONMAN New Zealand, but put an entire PH 1500 Tablet into ~750ml (24oz) of water. This is slightly more water than the science would suggest is optimal for preloading her blood sodium levels. Therefore, for future races we would recommend reducing the water content to ~500ml (16oz) with one PH 1500 tablet
      • Whilst on the bike, Rebecca had two 500ml (16oz) bottles - one contained one-and-a-half servings of PF 60 Drink Mix and the other had a single PH 1500 packet in. She also topped up her sodium intake with two Electrolyte Capsules. Along with the ~1L (32oz) of plain water that Rebecca picked up from aid stations throughout the ride, this brought her total fluid intake to ~439ml (15oz) per hour, with a relative sodium concentration of ~909 milligrams per litre (mg/32oz)
      • Going into the run, Rebecca reported “feeling well hydrated”, and managed to maintain this feeling throughout the marathon. She did this by carrying a Soft Flask of PH 1000 (Drink Mix), as well as picking up ~1.1L (33oz) of plain water and ~360ml (11oz) of Coca Cola from on-course aid stations
      • Overall, Rebecca consumed ~444ml (15oz) of fluid per hour, with a relative sodium concentration of ~604mg/L (mg/32oz). As someone with a low sweat sodium concentration of 553mg/L (mg/32oz), this hydration on the bike likely replaced a good amount of what she lost through sweating


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Rebecca began her pre-race fueling by starting the morning with a breakfast of two gluten-free pieces of toast with peanut butter and a banana
      • After feeling a lull in energy going into the run course on her last race at IRONMAN New Zealand, Rebecca wanted to combat this by taking an extra caffeine gel during the bike, along with an extra energy chew to increase her carbohydrate intake prior to the run, hoping to avoid that energy dip
      • Despite adding those extra carbs in, Rebecca still felt that her hard efforts on the bike to chase down her opponents took more out of her than she realised, and she perhaps could have benefited from a higher carb intake to support this harder effort
      • Rebecca aimed to combat this by taking a PF 90 Gel and three PF 30 Caffeine Gels on the run. After the race, she proposed that taking another PF 30 Caffeine Gel before the start of her run may have helped maintain her energy levels a little better, and reduce her perception of effort
      • Overall, Rebecca had a slightly lower average hourly carb intake than her previous race, consuming ~69g/h, compared with ~81g/h in New Zealand. To help combat these energy drop offs, Rebecca may want to undertake some gut training to increase her hourly intake towards 90g/h, which will help to increase her energy availability and stabilise her energy levels even during hard efforts
      • Rebecca also had a high caffeine intake during the race, ~635mg. Although this was likely above the 3-6mg/kg recommendation for endurance performance enhancement, Rebecca often consumes this level with no negative side effects, taking on ~597mg in New Zealand, showing she has a high caffeine tolerance


      • Rebecca enjoyed a successful race at the European Championships, and reported feeling well hydrated throughout, and mentioned an effective and fast recovery period of just five days
      • In future, Rebecca may look to alter the timing of her caffeine intake, to increase her energy levels before the run leg. This will help avoid that “energy lull” at the end of the bike, enabling her to feel more ready to run
      • Rebecca could also consider undertaking some gut training during key sessions to help her hit those higher carb numbers throughout races

    Key info

    Rebecca Clarke

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


    Overall Time
    Swim Time
    Bike Time
    Run Time

    Event information

    Full distance
    IRONMAN European Championship
    Frankfurt, Germany
    2nd July, 2023
    Swim Distance
    3.8km / 2.4mi
    Run Distance
    42.2km / 26.2mi
    Total Distance
    226.2km / 140.6mi
    Bike Elevation
    1,618m / 5,308ft
    Run Elevation
    114m / 374ft

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    15°C / 59°F
    Max Temp
    24°C / 75°F
    Avg Temp
    21°C / 70°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    Felt well hydrated.
    Energy levels
    Spent too long chasing without taking fuel in so ended bike feeling quite low
    Toilet stops
    Needed a pee at start of the run
    GI comfort
    Some stomach distress while running
    No cramping

    Rebecca's Thoughts

     I could've started the run in a better spot with better pace manangement and smarter positioning.

    Rebecca's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake6402,5004,140635604
    Per hour6926844468
    Bike and Run
    Total intake6102,5004,140635604
    Per hour7329949676
    Total intake3752,0002,200300909
    Per hour7539943960
    Total intake2355001,940335258
    Per hour71150582100

    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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