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Steph Clutterbuck's scorecard

IM 70.3 Staffordshire

Sunday 11th June, 2023

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 85g

    Carb per hour
  • 596mg

    Sodium per hour
  • 704ml

    Fluid per hour
  • 846mg/L

    Relative sodium concentration
  • 1.54mg/kg

    Caffeine per bodyweight
  • How Steph hit those numbers

    500ml x PH 1500
    2 x PF 30 Chews
    1 x PF 30 Caffeine Gel
    *** Tip: For sea swims, put a bottle of water at T1 to rinse your mouth out
    400ml x PH 1500 (Tablets)
    1L x PF Carb & Electrolyte Drink Mix
    2 x PF 90 Gel
    750ml x Plain water
    500ml x PH 1000 (Tablets)
    1 x PF 90 Gel
    600ml x Plain water

    How Steph's hydration and fueling went...

      • Steph is a member of the 2023 Zwift Tri Academy building towards the IRONMAN World Championships in Kona, Hawaii
      • This race was a stepping stone towards her long-distance training block, where she aims to qualify for Kona over double the distance at IRONMAN Vitoria-Gasteiz just four weeks after this race in Staffordshire
      • Taking the win at Staffordshire gave Steph huge confidence in her fitness, and how her newly developed fuel and hydration strategy played out in a race scenario


      • With weather forecasts predicting high temperatures on race day, Steph knew her hydration status would play a key role, so was vigilant in ensuring she started the race optimally hydrated. She did this by drinking a high-concentration sodium drink (PH 1500) the night before, and morning of the race
      • Steph used her strength in the swim to exit the water in first position, and set about extending her lead on her new custom Zwift Bike
      • On the bike, she had ~750ml (24oz) of plain water in her integrated hydration system, (which sits inside the frame of the bike), along with two highly concentrated bottles of carb and electrolytes
      • Steph’s main source of electrolytes came from the PH 1500 tablet in her smaller (400ml / 14oz) water bottle, and three servings of PF 60 Drink Mix in a 1L (32oz) bottle
      • In all, her fluid intake was solid at ~860ml (29oz) per hour for the bike discipline, with a relative sodium concentration of ~1,047 milligrams per litre (mg/32oz)
      • Steph recently had her sweat tested at the Zwift Tri Academy team camp in Austria, where she discovered she loses 1,105mg of sodium in each litre (32oz) of her sweat. This meant she’ll have replaced a good proportion of her electrolyte losses via the drinks she consumed
      • On the run, Steph decided to carry her own electrolytes, heading out of T2 with a Soft Flask of PH 1000, and sipping it throughout the 21.1km run
      • She also picked up cups of plain water from every on-course aid station, as temperatures were reaching 27℃ (80℉) and she could feel herself sweating a lot more.The overall sodium concentration she was consuming subsequently dropped due to the amount of plain water (~600ml / 18oz) she drank on the run, to ~846mg/L across the entire race
      • Steph didn’t experience any muscle cramps, but did start to fade towards the end of the half marathon, feeling like she “could barely concentrate” and “just wanted to drink”
      • Whilst Steph did a good job hydrating during the race, perhaps in future hot races, she may want to increase the strength of her Soft Flask electrolytes to help the water she drank be retained in the bloodstream. Alternatively, she could carry some Electrolyte Capsules with her so once her flask is empty, she can maintain her electrolyte intake by taking two capsules with every ~500ml (16oz) of water she drinks


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Ahead of the race, Steph gave her muscle and liver glycogen stores one final top-up with two PF 30 Chews. Then shortly before the swim start (~15 minutes) she had a PF 30 Caffeine Gel to optimise her blood glucose levels, and also reap the performance associated benefits of caffeine by the time it likely peaked in her bloodstream at the beginning of the bike
      • On the bike, Steph’s aforementioned highly-concentrated bottles contained her sole carbohydrate source. The ~1L (32oz) bottle with three servings of PF 60 Drink Mix provided 90g of carb, with her smaller ~400ml bottle containing two PF 90 Gels and a PH 1500 Tablet to give another 180g
      • Together this meant she averaged ~109g of carb per hour on the bike, which helped her maintain excellent energy levels throughout the ride. Furthermore, as she experienced no stomach discomfort, it suggests the gut training Steph has undertaken, with the help of her coach and former world record holder over the iron-distance, Tim Don, is well and truly paying off
      • On the run Steph carried a PF 90 Gel with her out of transition, and finished this after ~50 minutes of the run. Then, somewhat regrettably, Steph didn’t have her other PF 30 Gel, and finished the race with it still in her tri-suit pocket
      • On reflection, Steph couldn’t pinpoint why she didn’t take the gel, but felt it would certainly have helped prevent “feeling like a zombie” in the last ~4km of the race where she was willing the finish line to get closer
      • This feeling was likely a result of her body expecting more carbohydrates than it received on the run. Steph’s intake dropped from ~109g/h on the bike to just ~58g/h on the run, and going forward she should aim to reduce this drop off, which in turn will help maintain her energy levels right to the finish


      • In all, Steph had an excellent day at Staffordshire, taking the overall win by just over a minute, and with a few things to optimise for her next race
      • As an already accomplished triathlete, Steph has worked closely with the Sports Science team at PF&H to optimise her fuel and hydration strategy, and this race shows how she is still iterating her plan to suit her needs

    Key info

    Steph Clutterbuck

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


    Overall Time
    Swim Time
    Bike Time
    Run Time

    Event information

    Middle distance
    IM 70.3 Staffordshire
    Staffordshire, England
    11th June, 2023
    Swim Distance
    1.9km / 1.2mi
    Bike Distance
    90.1km / 56.0mi
    Run Distance
    21.1km / 13.1mi
    Total Distance
    113.1km / 70.3mi
    Bike Elevation
    850m / 2,789ft
    Run Elevation
    150m / 492ft
    Total Elevation
    1,000m / 3,281ft

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    24°C / 75°F
    Max Temp
    27°C / 81°F
    Avg Temp
    25°C / 77°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    I could have done with some more fluid on the bike
    Energy levels
    I really started to crash towards the end of the run, I was pretty much a zombie in the last 4km
    Toilet stops
    Just on the run
    GI comfort
    No issues at all
    No cramping

    Steph's Thoughts

     It was an awesome race, and I came away with what I needed

    Steph's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake3942,7503,250100846
    Per hour8559670422
    Bike and Run
    Total intake3642,7503,2500846
    Per hour896737960
    Total intake2722,2502,15001,047
    Per hour1099008600
    Total intake925001,1000455
    Per hour583166950

    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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