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Laura Siddall's scorecard

Challenge Roth

Sunday 5th September, 2021

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 74g

    Carb per hour
  • 138mg

    Sodium per hour
  • 653ml

    Fluid per hour
  • 212mg/L

    Relative sodium concentration
  • 11.31mg/kg

    Caffeine per bodyweight
  • How Laura hit those numbers

    500ml x PH 1500 (Tablets)
    2 x White bread rolls
    1 x Boiled egg
    1 x Black coffee
    1 x Energy gel (30g carb)
    1 x Caffeine tablet (50mg caffeine)
    *** Review technique if drinking much at this point!
    500ml x PH 500 (Tablets)
    500ml x PH 1500 (Tablets)
    10 x PF 30 Gel
    1.5L x Plain water
    500ml x Additional fluid in mixed drinks
    3 x Energy gel (25g carb)
    3 x PF 30 Gel
    2L x Plain water
    3 x Energy gel (25g carb)
    500ml x Coca Cola Original

    How Laura's hydration and fueling went...

      • Laura had a fantastic race at Challenge Roth, finishing in 2nd place after a very strong run leg which saw her gain position. She crossed the line in an impressive 8 hours and 25 minutes
      • She replicated some elements of her strategy from her previous race in Lanzarote, but also made some adjustments based on our advice


      • Laura preloaded before the race using PH 1500, which ensured she was starting the race optimally hydrated (Learn more). She used a combination of PH 1500 and PH 500 tablets on the bike to meet her sodium needs. Previously she’s moved onto using our Electrolyte Capsules once she has depleted her pre-mixed bottles, but didn’t on this occasion
      • Overall, her sodium intake was on the lower side (~138mg sodium per hour), which was around half her average intake at Lanzarote (~262mg/hr)
      • Laura’s sodium consumption was especially low during the run leg (~22mg/hr) and, given that she reported some twinges of cramp towards the latter end of the run, it may be in her best interest to up her intake in future races. Electrolyte Capsules would be a useful option here
      • Laura’s fluid intake throughout Challenge Roth was good and reflected the increasing temperature throughout the race. She drank an average of ~653ml/hr (~22oz/hr) throughout
      • Unusually, Laura’s fluid intake was higher during the run (~843ml/hr; 28oz/hr) than during the bike (~682ml/hr; 23oz/hr). This may have been due to the temperature increasing as the race progressed, as Laura commented that it was a warm run
      • These volumes are good and well within the expected range. At her previous race in Lanzarote she drank an average of 545ml/hr (18oz/hr)
      • That said, Laura commented that she felt she may not have drunk enough. This requires further interrogation as Laura also peed twice on the run, which would suggest she was well-hydrated (and maybe even drinking slightly too much, as peeing at this stage in the race more than once is unusual)
      • The relative sodium concentration of Laura’s intake was ~212mg/L. Whilst Laura isn’t a super 'salty sweater' (her sweat sodium concentration falls around the 600mg/L mark), we know from some recent sweat rate data-gathering that she can at times have a sweat rate verging on ‘high’ (>1.5L/hr; >51oz/hr)
      • So, whilst Laura needn’t be heavily supplementing with sodium, it’s likely that a higher relative intake may be beneficial to her performance, especially in races of this duration and in warmer conditions


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Laura consumed ~30g of carb 15 minutes before the race by eating an energy gel alongside a Pro Plus caffeine tablet (50mg caffeine). She also had a carb-rich breakfast and coffee, and these tactics will have allowed her to start the race with her fuel stores topped off and perceived energy levels high (learn more)
      • Laura’s carb intake on the bike was made up of four flasks, two of which contained solely PF 30 Energy Gels, one with PF 30 Gels and an energy gel with caffeine and one just with the energy caffeine gel. Similarly on the run, she had two flasks both containing PF 30 Gels and energy gels with caffeine
      • It was good to see Laura’s average race intake fall in the middle of our recommended range at 74g/hr. This was a higher carb intake than her average of 63g/hr at IRONMAN Lanzarote a couple of months before this race
      • Laura hit 86g of carb per hour during the bike and a very solid 73g/hr on the run. At Lanza, she only hit 69 and 65 grams of carb per hour for the bike and run, respectively
      • This is an improvement across the board and it’s great to see Laura has increased her carbohydrate intake between these two races, likely through some training of her gut
      • Given the positive relationship between increasing carbohydrate intake and performance outcomes, this change was no doubt instrumental in Laura’s strong and dominant finish at Roth
      • The recommended caffeine dose for performance is 3-6mg per kilogram of bodyweight. Laura’s body weight is currently around 61kg, so her recommended range is about 183-366mg
      • Laura actually consumed around ~690mg of caffeine in total over the race which equates to 11.3mg/kg BW. That dosage is clearly higher than the guidelines, but caffeine response is highly variable and individual. We know that Laura is an athlete who habitually uses a lot of caffeine during her races
      • In the past, Laura has consumed a lot more caffeine than she did at Roth. We encouraged Laura to dial back her caffeine intake after she reported sleeping poorly following major races and what we’re seeing now is a more sensible intake
      • If Laura wanted to further reduce her intake, she could reduce the number of caffeinated energy gels she takes


      • Laura had a fantastic race at Roth. She did a really good job of meeting her carbohydrate needs and we saw her increase her carb intake from her previous race at Lanzarote, whilst not suffering any GI discomfort as a result (she reported 10/10 which denotes no issues, fine all day)
      • She felt she fueled enough and had an overall race satisfaction of 8 out of 10. Improvements to Laura’s hydration and fueling strategy going forward might include increasing the proportion of sodium she’s taking in relative to her fluid intake and possibly some further refinement to her caffeine consumption

    Key info

    Laura Siddall

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


    Overall Time
    Swim Time
    Bike Time
    Run Time

    Event information

    Full distance
    Challenge Roth
    Bavaria, Germany
    5th September, 2021
    Swim Distance
    3.8km / 2.4mi
    Bike Distance
    170.0km / 105.6mi
    Run Distance
    42.2km / 26.2mi
    Total Distance
    216.0km / 134.2mi
    Bike Elevation
    2,100m / 6,890ft

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    12°C / 54°F
    Max Temp
    25°C / 77°F
    Avg Temp
    20°C / 68°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    Toilet stops
    Twice on the run
    GI comfort
    Twinges but not full-on cramps

    Laura's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake6261,1655,500690212
    Per hour7413865382
    Bike and Run
    Total intake5971,1295,500640
    Per hour8115374787
    Total intake3791,0653,000300355
    Per hour8624268268
    Total intake218652,50034026
    Per hour7322843115

    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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