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Amy Cuthbertson's scorecard

IM 70.3 Luxembourg

Sunday 19th June, 2022

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 54g

    Carb per hour
  • 327mg

    Sodium per hour
  • 620ml

    Fluid per hour
  • 527mg/L

    Relative sodium concentration
  • 0mg

    Total caffeine
  • How Amy hit those numbers

    500ml x PH 1500 (Tablet)
    1 x Can of Red Bull
    0.3 x Loaf of chocolate chip brioche
    *** Review technique if drinking much at this point!
    1L x PF Carb & Electrolyte Drink Mix mixed with PH 500 (Drink Mix)
    0.5L x PH 500 (Drink Mix)
    5 x PF 30 Gel
    2 x Energy bar (21g carb)
    250ml x PH 500 (Drink Mix)
    2 x PF 30 Gel
    1.8L x Plain water

    How Amy's hydration and fueling went...

      • Amy Cutherbertson is one of ten female athletes that the Precision Fuel & Hydration Team have been working with in collaboration with the Voxwomen Performance Project. Upon joining the project, as someone who could ‘ride well, ran a bit, but couldn’t swim’, Amy’s personal goal was to complete a middle distance triathlon at the end of the six months
      • With the help of the Sports Science Team and the team at Supersapiens, Amy, learned how best to fuel and hydrate to optimise her performance. This helped her to achieve her goal, in a time of 6 hours and 56 minutes
      • On race day, Amy did a great job at managing her fuel and hydration needs despite the very hot weather conditions (highs of ~32℃/90℉), following her plan and hitting her targets on the bike and having the confidence to listen to her body on the run


      • Having checked the forecast ahead of time, Amy knew she would be racing in hot conditions >30℃/86℉ and would therefore be incurring significant sweat losses. With that in mind, to ensure she started well-hydrated, Amy drank 500ml/16oz of PH 1500 alongside her breakfast; a strategy which encourages the body to retain a greater proportion of the fluid drunk as well as starting with acutely more sodium on board
      • During the race, all three of Amy’s 750ml/24oz bike bottles were filled with PH 500 (Drink Mix), with two of them also containing PF 30 Drink Mix. Amy depleted all three bottles on the ride, drinking an average of ~631ml/h (21oz/h), and then chose to run out of transition with another 500ml/16oz flask of PH 500
      • At this point, temperatures were high, and what Amy was craving the most was just plain water. With that being the case, Amy drank half of her PH 500 flask before discarding it and drinking “as much water as I could get my hands on”
      • Amy estimated that she drank ~18 cups of plain water during the run (~6 cups per lap of the three lap course) equating to ~1.8L/60oz of water (~100ml per cup). In total, we estimate that Amy drank ~2.05L/64oz on the run, averaging ~872ml/h (29oz/h). This is a relatively high average fluid intake but it reflects the high temperatures Amy was racing in
      • The craving for plain water Amy experienced on the run is a reflection of the hot temperatures at that stage in the race, as well as, being a likely consequence of drinking only sodium-rich drinks during the bike leg. The relative sodium concentration of Amy’s drinks on the bike averaged ~951mg/L, a moderate-to-high concentration. Amy hasn’t had a Sweat Test so we don’t know her sweat sodium concentration (how many milligrams of sodium she loses per litre of sweat), however she perceives her sweat sodium losses to be low, as well as her sweat rate. Therefore, her net sodium losses may not have been too high
      • Amy’s pre-mixed bottles were great choices on the bike but balancing these with some plain water to dilute the relative sodium concentration would be advised for future, warmer races of a similar duration
      • Amy rated the appropriateness of her hydration strategy an 8 (out of 10), but not for lack of a suitable plan, instead, due to a lack of available water on the run, saying “two aid stations per 7km lap wasn’t enough in plus 30℃”


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Amy ate her tried and tested breakfast of a third of a large chocolate chip brioche loaf alongside a can of Red Bull before the race. This ensured she was starting the event with topped up glycogen levels
      • Amy could consider in future races taking ~30g of simple carb, for example one PF 30 Gel, in the 15 minutes before the gun. This is a strategy which is used by athletes to spike blood glucose levels at the beginning of exercise, sparing muscle glycogen in the early stages for use later. That said, it is a strategy which is considered to be an athletes personal preference and needs testing in training before race day
      • Across the 70.3 race, Amy consumed a total of ~375g of carb, averaging ~54g per hour which falls just short of the recommendations of 60-90g/h for a race of this intensity and duration. However, this doesn’t tell the full story of Amy’s fueling as she did meet the upper end of this recommendation on the bike but struggled to eat as much as she planned on the run due to the conditions, bringing her average carb intake down
      • On the bike, Amy averaged ~86g/h, with her three 750ml/24oz bottles each containing one PH 500 (Drink Mix) and two containing an additional serving of PF 30 Drink Mix. Amy also took five PF 30 Gels and two energy bars (~21g carb each), following the rough plan to eat something every 30 minutes
      • The decision to use a variety of carb sources reduces the chance of flavour fatigue and can improve morale at difficult times
      • On the run, Amy had planned to use PF 30 Gels and Haribo sweets to meet her fueling needs as this had worked well in her longer training runs. Unfortunately, in the heat of the day, Amy reported that “it was impossible to eat Haribo, I couldn’t swallow them”
      • In the end, Amy took just two gels on the half marathon (~29g/h), prioritising drinking plain water from aid stations to quench her thirst
      • Amy rated her GI comfort in the race as 8 (out of 10), rather than this being a result of taking in too much, she commented that, at times it was hard to eat as a result of her food and fluids being hot
      • Whilst Amy did caffeinate before the race with a can of Red Bull, she could have benefitted from ‘topping up’ her caffeine dose as the race duration (~7 hours) exceeded caffeine’s half life of 3-4 hours, to provide an additional mental, and physical, boost


      • Amy did a great job in her first ever middle distance triathlon in very challenging conditions; following her plan on the bike and adapting well on the run!
      • One adjustment to Amy’s strategy would be to drink some plain water on the bike alongside her pre-mixed bottles. This change will slightly reduce the relative sodium concentration of Amy’s consumption, which may have a positive influence on her strong craving for water in the latter stages of the race

    Key info

    Amy Cuthbertson



    Overall Time
    Swim Time
    Bike Time
    Run Time

    Event information

    Middle distance
    IM 70.3 Luxembourg
    Region Moselle, Luxembourg
    19th June, 2022
    Swim Distance
    1.9km / 1.2mi
    Bike Distance
    90.1km / 56.0mi
    Run Distance
    21.1km / 13.1mi
    Total Distance
    113.1km / 70.3mi

    Race conditions

    Weather Conditions
    Very Hot
    No Rain
    Min Temp
    27°C / 81°F
    Max Temp
    32°C / 90°F
    Avg Temp
    30°C / 86°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    This is down to the lack of availability of fluid on the run, not down to my plan
    Energy levels
    Toilet stops
    Once entering T1 but not again
    GI comfort
    No cramping

    Amy's Thoughts

     I hadn’t factored in how hard it would be to eat in the heat for the run. I had tried and tested what I wanted to eat in training and it was fine, but on the day I simply couldn’t swallow the haribo I planned to eat

    Amy's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake3752,2654,3000527
    Per hour543276200
    Bike and Run
    Total intake3752,2654,3000527
    Per hour633837270
    Total intake3062,1402,2500951
    Per hour866006310
    Total intake691252,050061
    Per hour29538720

    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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