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Fenella Langridge's scorecard

Challenge Roth

Sunday 25th June, 2023

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 93g

    Carb per hour
  • 885mg

    Sodium per hour
  • 614ml

    Fluid per hour
  • 1,440mg/L

    Relative sodium concentration
  • 8.77mg/kg

    Caffeine per bodyweight
  • How Fenella hit those numbers

    750ml x PH 1500 (1 x Tablet)
    1 x PF 30 Gel
    2 x Slices of White Bread with Honey
    1 x Cup of Rice with Honey and Banana
    1 x Mug of Coffee
    375ml x PH 1500 (Drink Mix)
    1 x PF 30 Caffeine Gel
    *** Try to avoid drinking too much at this point in the race!
    750ml x PH 1500 (Drink Mix)
    15 x PH Electrolyte Capsule
    0.5 x PF 30 Energy Chews
    1 x PF 30 Energy Gel
    2 x PF 30 Caffeine Gel
    4 x PF 90 Energy Gel
    2.25L x Plain water
    1.125L x PH 1500 (Drink Mix)
    4 x PH Electrolyte Capsule
    6 x PF 30 Energy Gel
    2 x PF 30 Caffeine Gel
    750ml x Plain water

    How Fenella's hydration and fueling went...

      • Fenella raced at Challenge Roth for the third year in succession, having finished 3rd and 2nd at her previous attempts
      • After leading out of the water, Fenella set off on the 180km bike course alongside five-time IRONMAN World Champion Daniella Ryf. Ryf is renowned for her bike pedigree, and Fenella quickly realised her bike legs weren’t as she’d hoped after suffering with illness during the few weeks prior to the race. This meant that she rode the majority of the course solo, but still managed to keep her spirits high with the help of the infamous crowds lining the course in Roth
      • Fenella closed out the race with her first sub-three hour marathon in Roth, coming home in 4th place against one of the highest quality fields in 2023, on a day where World Records were broken in both the men’s and women’s races


      • Before the race, Fenella drank plenty of water (~1.5L / 48oz) to try and start the race hydrated. In this water, she mixed two PH 1500 Tablets, but for future races we’d recommend reducing the quantity of water these tablets are mixed in, to increase the relative sodium concentration to 1,500mg per litre (mg/32oz)
      • This concentration has been shown to optimally increase blood plasma volume and increase the body’s ability to thermoregulate, both of which are important when preparing to undergo some serious sweating
      • Fenella’s hydration strategy has changed somewhat in the past few months, moving from primarily pre-mixed electrolyte drinks like at Roth 2021 and Roth 2022, to a more water-based strategy with Electrolyte Capsules to maintain her sodium balance
      • This time round, Fenella drank ~2.25L (~79oz) of plain water, and swallowed 15 Electrolyte Capsules. She still kept one 750ml (24oz) bottle with a PH 1500 packet in, meaning her total bike fluid intake had a relative sodium concentration of ~1,500mg/L (mg/32oz)
      • Fenella loses 1,331mg of sodium in each litre (32oz) of her sweat, which puts her firmly in the “salty sweater” camp. With temperatures high in Roth on race day (~25℃ / 77℉), and her sweat losses likely high, this combined sodium and fluid intake (~641ml / 21oz per hour) on the bike will have ensured she replaced a good proportion of her losses
      • During the run, Challenge Roth has a rule unlike other long-distance races, whereby athletes can pick up their own supply of fuel and hydration from their support crew shortly after every aid station. This eliminates the need to carry gels and bottles for long periods
      • Fenella’s partner and coach, Billy, handed her three Soft Flasks filled with PH 1500 at regular intervals throughout the marathon. She managed to drink around three-quarters of each of these, and also picked up ~750ml (24oz) of plain water
      • To top up her electrolyte intake whilst drinking the plain water on the run, Fenella also took four Electrolyte Capsules, to bring her relative sodium concentration up to ~1,433mg/L (mg/32oz)
      • Fenella’s higher fluid and electrolyte intakes are vastly different to what she hit during the bike and run last year at Challenge Roth. In 2022, where temperatures were marginally higher (~28°C / 82°F), Fenella aimed to drink much more on the run to account for her greater sweat losses, this reduced the sodium concentration to just ~790mg/L
      • The more stable intake this year will have helped her body continually process similar concentration drinks to what she was sweating out, making the transition back into her bloodstream more efficient and reducing the likelihood of high/low blood sodium levels


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • To fully stock her glycogen stores ready for the eight-and-a-half hours of racing to come, Fenella had a very high-carb breakfast containing plenty of white bread, rice, honey and bananas
      • She also started to bring her blood caffeine levels up with a mug of coffee, as Fenella has reaped the ergogenic benefits of the stimulant on numerous occasions previously, and finds it works well for her. Then shortly before the race began, Fenella took a final carb hit to prime her blood glucose levels, and further increase the caffeine in her system with a PF 30 Caffeine Gel
      • Throughout the race, Fenella’s water bottles all had some carbohydrates in, as she’d squeezed a PF 90 Gel into one, a PF 30 Gel into another, and three PF 90 Gels in her third bottle, alongside taking two PF 30 Caffeine Gels and half a PF 30 Chew. Fenella’s carb intake was solid at ~102g per hour, closely matching her ~104g/h on the bike in 2022
      • During the run, this dropped slightly to ~92g per hour, which was spot on her pre-race plan to take one gel every 20 minutes, with PF 30 Caffeine Gels replacing PF 30 Gels at ~40 minutes and 1 hour 40 minutes
      • Overall, this meant she averaged ~93g of carb per hour, which is almost exactly the upper recommendations from our Fuel and Hydration Planner. This high intake for an athlete of just ~57kg is testament to the extensive gut training Fenella does on a regular basis to increase her tolerance and reduce the risk of gastrointestinal issues
      • To support this, Fenella was able to hit this high carb intake whilst rating her GI comfort 10/10, and stating that her energy levels were great throughout


      • Fenella produced another good performance at Challenge Roth, and the commentators once again drew attention to her relentless happiness throughout and genuine joy to be racing the iconic course
      • Her superbly executed fuel and hydration strategy in a hot race, against a stacked field should give her confidence as part of her build towards the IRONMAN World Championships in Hawaii

    Key info

    Fenella Langridge

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


    Overall Time
    Swim Time
    Bike Time
    Run Time

    Event information

    Full distance
    Challenge Roth
    Roth bei Nürnberg, Germany
    25th June, 2023
    Swim Distance
    3.8km / 2.4mi
    Bike Distance
    180.2km / 112.0mi
    Run Distance
    42.2km / 26.2mi
    Total Distance
    226.2km / 140.6mi
    Bike Elevation
    1,567m / 5,141ft
    Run Elevation
    167m / 548ft

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    15°C / 59°F
    Max Temp
    29°C / 84°F
    Avg Temp
    25°C / 77°F

    Fenella's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake7917,5635,2505001,440
    Per hour9388561458
    Bike and Run
    Total intake7547,1884,8754001,474
    Per hour9893863652
    Total intake4804,5003,0002001,500
    Per hour10296164143
    Total intake2742,6881,8752001,433
    Per hour9290162867

    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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