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Marnie Ponton's scorecard

Canberra Marathon

Sunday 10th April, 2022

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 28g

    Carb per hour
  • 0mg

    Sodium per hour
  • 110ml

    Fluid per hour
  • 0mg/L

    Relative sodium concentration
  • 0mg

    Total caffeine
  • How Marnie hit those numbers

    1 x PF 30 Energy Gel
    1x Mug of black coffee
    2 .5 x PF 30 Energy Gel
    300ml x Plain water

    How Marnie's hydration and fueling went...

      • Marnie entered the Canberra Marathon with the intention of running a qualifying time for the 2022 World Marathon Championships which stands at 2 hours, 29 minutes and 30 seconds. Marnie went out at the pace required to run her target time, but unfortunately suffered in the second half of the race and finished in a time of 2:43:30
      • Marnie still managed to win the race by an impressive 10 minutes and 3 seconds, but she fell short of her pre-race target and has already set her sights on achieving this qualifying time at the Gold Coast marathon in July
      • Marnie’s original plan was to use the elite drinks tables to pick up her bottles of PF 30 Drink Mix, but saw the aid stations “weren’t great” and it wouldn’t have been easy to access her drinks during the race. For this reason, Marnie decided that using her own bottles wasn’t a viable option, and planned to utilise the on-course water stations instead
      • This was Marnie’s second marathon attempt in seven days after she DNF’d a little before halfway of the Newcastle marathon the weekend prior, and in hindsight felt she wasn’t completely recovered for this race


      • Marnie describes herself as a light-to-moderate sweater, and decided to preload the day before with PH 1500. She mixed this in ~1.25L/42oz of water, which will have diluted the relative sodium concentration of her drink to ~600mg/L. In addition to this, Marnie drank ~1L/32oz of plain water
      • Marnie says she was peeing quite a lot the night before the race, which indicates she may have over hydrated, a practice that can be counterproductive and potentially reduce blood plasma volume. To prevent this, we would recommend Marnie follows our preloading protocol by drinking PH 1500 in ~500ml/~16oz of water. This will ensure the sodium concentration is not diluted, and will prevent over-excretion of vital electrolytes and fluids as a result of acute overhydration
      • Marnie managed to drink ~300ml/10oz of water during the race, regularly grabbing cups at aid stations as and when she desired. Due to not having her own bottles of PF 30 Drink Mix on course, she may have consumed less fluid than originally planned
      • Nonetheless, during races of this intensity, it can often be difficult for athletes to consume fluid whilst moving at such fast speeds, operating at close to maximal effort. So considering this, Marnie did a good job at getting ~150ml/5oz of fluid down per hour in the earlier parts of the marathon
      • Marnie didn’t take on any sodium during the race. Considering the high intensity Marnie races at, we would recommend she consumes some sodium to replace a larger proportion of the sodium she’s losing in sweat, especially during races in hotter conditions when her net sweat losses are likely to be higher. She may consider using some Electrolyte Capsules when there’s no opportunity to collect pre-made electrolyte drinks on course


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Prior to the race, and perhaps due to the early start at Canberra (6:15am), Marnie only had a mug of black coffee ~60 minutes before and a PF 30 Energy Gel ~40 minutes before the gun went off. Marnie’s full-time work schedule means the majority of her training is done very early in the morning, and she’s become accustomed to running without eating prior, and chose not to change this on race morning
      • We would typically recommend a carbohydrate hit to come within the final 30 minutes before the race start, but having one slightly further out will still have helped Marnie top up her muscle glycogen levels and get into her bloodstream quickly, thus enabling her stored glycogen to be saved for later in the race
      • Marnie’s pre-race plan consisted of a PF 30 Energy Gel every 9-10kms (every 32-35 minutes), taking 4 gels in total. However, upon opening her third gel at ~30km, she only ate half of it, and had nothing for the rest of the race
      • Marnie knew she had the win in the bag at this point, and that her target time had slipped away, therefore focused on simply “making it to the finish line”
      • Overall, Marnie took ~75g of carbs (~28g/hr) during the race, which is below the recommended 60-90g/hr range provided by our Quick Carb Calculator for a marathon of this intensity
      • In an attempt to avoid the “blowing up” she experienced just over half way, we would suggest that Marnie consumes a high carb meal of between 1-4g per kilogram of bodyweight 1-4 hours prior to future races. This can significantly enhance endurance performance by increasing available energy stored in both the liver and the muscles. This may be something Marnie needs to practice in training by setting her alarm even earlier, to ensure she is comfortable running after consuming a high-carb meal
      • Marnie may also want to consider bumping up her carb intake during the race to within the recommended ranges, as this is correlated with increased endurance performance
      • Furthermore, Marnie’s initial plan was to use PF 30 Drink Mix on course as it would have been an efficient way to meet her carb, sodium and fluid needs. Ahead of future marathons, we recommend that Marnie trials using a mixture of fuel sources(drink mix and gels) to help her reach these higher carbohydrate recommendations, and should unforeseen circumstances arise again, she is comfortable with using different products


      • In all, Marnie was disappointed with her overall performance, rating her race satisfaction at 2/10, primarily because she didn’t achieve what she wanted
      • Marnie further went on to describe how she loves the feeling of winning races, but when it comes after a poor personal performance, it can be bitter sweet
      • There are some positives that Marnie can take away from this race, including how she employed her wealth of experience to adapt her fueling plan, so she avoided the dreaded stomach cramps
      • For future races, Marnie will be better recovered in the lead up, which will undoubtedly improve her performance. She should also try to optimise her pre-race hydration status by maintaining the intended concentration of the PH 1500 by preloading with one tablet mixed in ~500ml (~16oz) of water the night before, and the morning of the race
      • Further to this, Marnie should look to include some sodium intake during her next race on the Gold Coast, perhaps by utilising some Electrolyte Capsules
      • Fuelling better in the 2-3 hours before the start will also help Marnie improve her future performances

    Key info

    Marnie Ponton



    Overall Time

    Event information

    Canberra Marathon
    Canberra, Australia
    10th April, 2022
    Total Distance
    42.2km / 26.2mi

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    15°C / 59°F
    Max Temp
    21°C / 70°F
    Avg Temp
    19°C / 66°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    Energy levels
    Before blowing up I was a solid 7/10, and fell to a 2/10 after halfway
    Toilet stops
    GI comfort
    Second half, I didn't want another gel
    No cramping

    Marnie's Thoughts

     I like winning, but I didn't achieve what I wanted

    Marnie's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake75030000
    Per hour2801100

    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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