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Robyn Cassidy's scorecard

Helvellyn Sky Ultra

Saturday 15th July, 2023

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 62g

    Carb per hour
  • 269mg

    Sodium per hour
  • 375ml

    Fluid per hour
  • 717mg/L

    Relative sodium concentration
  • 0mg

    Total caffeine
  • How Robyn hit those numbers

    500ml x PH 1500 (Tablet)
    50g x Porridge with peanut butter and jam
    1 x Cup of black coffee
    1L x PF Carb & Electrolyte Drink Mix
    4 x PF 30 Gel
    1 x PF 30 Chews
    500ml x Plain water
    1 x Energy gel (22g carb)
    0.5 x Energy bar (41g carb)
    1 x Energy gel (33g carb)
    300ml x Hydration powder (312mg sodium)

    How Robyn's hydration and fueling went...

      • In preparation for her ‘A’ race of the year, the epic six-day Dragon’s Back ultra, Robyn Cassidy took part in the Lake District’s Helvellyn Sky Ultra
      • After mixed successes with her fuel and hydration strategy in 2023, this race allowed Robyn to test her latest strategy at a course which replicates a similar experience to day one of the Dragon’s Back
      • Despite storms (and therefore a shortened, flatter route of 42km / 26 miles), Robyn executed a solid performance to finish 1st! She implemented the majority of her plan but experienced some dips and difficulties towards the back end of the race that she’ll be looking to iron out at the Dragon’s Back…


      • For the first time before a race, Robyn followed a preloading protocol by drinking 500ml (16oz) of PH 1500, both the night before and morning of the race, and as a result she reported feeling “really hydrated at the start”
      • Robyn’s hydration strategy during the race was predominantly made up of two 500ml (16oz) bottles of PF 60 Drink Mix. She refilled one bottle with plain water at ~16km (10 miles) and the other with the on course electrolyte mix (312mg sodium) at ~30km (18.5 miles)
      • Robyn had intended to fill up her bottles at the three available water stops and mix in PH 1000 to drink a total of 3L (96oz). However, on the day Robyn didn’t drink as much as she had planned, her drinking “slowed down from halfway” because she “didn’t want to drink any large volumes due to a sloshing feeling” in her stomach
      • Instead she drank a total of ~1.8L (63oz) which averaged out as ~375ml (13oz) per hour, but was greater towards the start of the race and tapered off. Although we don’t know Robyn’s exact sweat losses over the race, from her subjective feedback and post-race headache and dark pee colour, it was likely she was under doing her fluid intake
      • On top of this, Robyn’s fluid intake early on in the race was solely made up of energy drink mix. This initial carb quantity is more than she had taken on previously and taking in this much carb-rich liquid early on can cause it to rush to the gut and overwhelm the intestines’ capacity to absorb, which can lead to the discomfort and bloating she reported
      • Robyn may wish for one of her bottles to be solely hydration focused, for example containing PH 1000, in an attempt to avoid these issues and allow her to drink more fluid over the race
      • Robyn consumed a relative sodium concentration of ~717mg per litre (32oz) from PF 60 Drink Mix and the on course electrolyte drink. On the surface, this seemed like an adequate sodium intake alongside the low volume of fluid she drank, but going forward collecting sweat rate data and getting a sweat test will help Robyn dial in her hydration strategy further


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Robyn followed a textbook pre-race fueling plan by consuming a carb-rich breakfast in the morning to top up her glycogen stores, alongside a cup of coffee to get caffeine in her bloodstream in attempt to benefit from its ergogenic effects later in the day
      • She may want to practise implementing a final carb dose within the last 30 minutes before the race, for example having a PF 30 Gel or PF 30 Chew, to spike her blood glucose as she begins the run and stave off using her glycogen stores until later on
      • During the race, Robyn’s carbohydrate intake predominantly came from PF 60 Drink Mix and a range of gels (aiming for 1-2 per hour). She also supplemented this with a pack of PF 30 Chews and half an energy bar she picked up on course, which is a good way to get extra fuel on board and avoid flavour fatigue
      • This meant Robyn averaged ~62g/h over the 4 hours and 48 minutes. This is a solid intake for Robyn who has previously taken in much lower levels of carbohydrate and has been training her gut by gradually building up her intake in training sessions
      • Robyn started with an effective timing strategy by fueling 30 minutes into the race, instead of waiting until 60 minutes in as she had previously. She had planned to fuel every 30 minutes but lost track of this towards the second half of the race
      • In line with losing track of her fueling, Robyn mentioned that although her GI comfort and energy levels started high (10/10), around the halfway point she had some GI stress (6/10) and from 30km her energy levels dipped to 4 or 5 out of 10
      • As Robyn started out with her two 500ml (16oz) bottles of PF 60 Drink Mix and her proactive gel strategy, her carb intake was likely higher in the first two hours and lower for the latter part of the race. Therefore, she was likely taking on more than she had previously used (40-50g/h) at a high race intensity which could have further led to her gut discomfort
      • Robyn should continue to train her gut to increase her tolerance for 60g/h+ because greater carb quantities are crucial for endurance performance, especially over multi-day ultras like Robyn’s next race
      • Caffeine has a half life of ~4-5 hours, therefore Robyn may have also benefited from periodically replenishing the levels of caffeine in her blood in an attempt to retain the benefits


      • Overall, Robyn had a great result at the reduced distance Helvellyn Sky Ultra and was “happy with the outcome and result”, but knows there were areas that “could have been better” so rated her race satisfaction a 6 out of 10
      • Robyn fueled and hydrated well ahead of the race and started excellently. Going forward with her multi-day ultra later in 2023 in mind, the focus for Robyn will be to continue to train her gut to tolerate higher carb quantities and being more proactive with her hydration strategy

    Key info

    Robyn Cassidy



    Overall Time

    Event information

    Helvellyn Sky Ultra
    Cumbria, England
    15th July, 2023
    Total Distance
    42.0km / 26.1mi
    Total Elevation
    1,950m / 6,398ft

    Race conditions

    Weather Conditions
    Min Temp
    13°C / 55°F
    Max Temp
    17°C / 63°F
    Avg Temp
    14°C / 57°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    Felt I had a good plan and started well but got a sloshing feeling in my stomach halfway through
    Energy levels
    Started at a 9 but dropped throughout and then were quite low (4/5) from the 30km mark
    Toilet stops
    GI comfort
    I felt great (10) until about half way then I struggled to eat and drink as much as I would have liked
    No cramping

    Robyn's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake2961,2911,8000717
    Per hour622693750

    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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