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Julie Dunkle's scorecard

IRONMAN World Championships

Saturday 7th May, 2022

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 54g

    Carb per hour
  • 1,120mg

    Sodium per hour
  • 852ml

    Fluid per hour
  • 1,314mg/L

    Relative sodium concentration
  • 64mg

    Total caffeine
  • How Julie hit those numbers

    750ml x PF Energy Drink Mix + PH 500 tablet
    750ml x 2 x PH 1500 tablets
    1 x mug of coffee with coconut milk
    1 x PF 30 Gel
    *** Tip: For sea swims, put a bottle of water at T1 to rinse your mouth out
    1.5L x PH 1000 (Tablets)
    12 x PH Electrolyte Capsule
    1.5L x PF Carb & Electrolyte Drink Mix
    6 x PF 30 Chews
    3L x Plain water
    1.5L x Energy drink (22g carb)
    1 x Energy gel (45g carb)
    1L x PH 1000 (Tablets)
    16 x PH Electrolyte Capsule
    500ml x PF Carb & Electrolyte Drink Mix
    3 x PF 30 Gel
    975ml x Plain water
    300ml x Energy drink (22g carb)
    400ml x Cola
    100ml x Red Bull

    How Julie's hydration and fueling went...

      • Julie went into this World Championship race with high hopes of finishing on top of the podium, and she executed a brilliant race which landed her there
      • Weather conditions dominated how athlete fueling and hydration strategies played out. Temperatures reached ~35℃/94℉ during the marathon and the ~12% humidity meant it was a very dry heat that provided a stern test for athletes
      • Julie had a very good swim, exiting the water first in her age group. She continued this dominance onto the bike, where she set the fastest time in her age group by 30 minutes!
      • She backed up these solid performances with the 4th fastest run of her age group, to take the world championship title by over 45 minutes
      • Altogether, Julie was pleased with how her day panned out, saying it was “a dream come true”


      • Julie preloaded her sodium levels by drinking ~750ml/26oz of water with 2 x [PH 1500 (Tablets)]((https://www.precisionhydration.com/products/ph-1500-low-calorie-electrolyte-supplement/) the night before and the morning of the race. Whilst this is a greater relative sodium concentration than we typically recommend preloading with, Julie experienced no negative side effects, and began the race well hydrated and with optimal blood volume
      • In total, Julie consumed just over ~10L/351oz of fluid throughout the race, averaging ~852ml/hr. Considering the first hour of the race was spent swimming (where hopefully she wasn’t drinking too much!), Julie averaged 943ml/hr during the bike and run. Considering in similar environmental conditions to St George, Julie has experienced a sweat rate of ~2L/hr, this may be below her required fluid intake. However, due to the cooler starting temperatures, it will have taken her longer to start sweating at this rate
      • Julie’s total sodium intake was ~13,174mg, averaging 1,120mg/hr for the whole race, and a relative sodium concentration of ~1314mg/L. Considering Julie’s sweat sodium concentration of 1167mg/L, as measured by our Sweat Test, she did a solid job at replacing a large proportion of her sodium losses
      • Julie didn’t get any muscle cramps nor did she experience any indicators she was overdoing the sodium such as craving plain water, disliking the taste of salt, or headaches, further suggesting she was hitting her numbers appropriately
      • To hit these impressive numbers, Julie drank three ~750ml/26oz bottles containing PF 30 Drink Mix and a PH 1000 tablet, and picked up four ~750ml/26oz bottles of plain water on the bike. Julie supplemented these bottles of water by taking twelve Electrolyte capsules
      • Julie planned to collect two additional bottles from the special needs aid station on the bike. She froze these two bottles overnight, anticipating the high temperatures on race day and hoping they would have a cooling effect by being partially frozen. Unfortunately when she picked up the bottles, the still entirely frozen drinks had caused the bottles to expand, and thus they no longer fit in her bike’s bottle cages. Subsequently, Julie was forced to discard these bottles and replace their contents using the on-course aid stations
      • During the run, Julie hit her hydration strategy by picking up ~1.5L/52oz of PF 30 Drink Mix with two PH 1000 tablets in it, ~13 cups of water and ~6 cups of on-course electrolyte drink. Once again, Julie supplemented these drinks by taking 16 PH Electrolyte capsules


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Julie had two large pancakes for breakfast which are high in carbs to give her glycogen stores a final top-up before the race
      • Julie also had a cup of coffee with her breakfast. Caffeine is a known performance enhancer, with studies showing reductions in perceived effort, increased endurance capacity and improved focus and mental performance after it’s ingestion
      • In the final 15 minutes before the start, Julie also had a PF 30 Gel which will have hit her bloodstream quickly, sparing her stored glycogen for later in the race
      • Throughout the race, Julie relied on PF 30 Drink Mix, PF 30 Chews and PF 30 Gels to fulfil her carbohydrate needs
      • In total, Julie took ~639g of carb throughout the whole race, averaging ~54g/hr. This is very close to her original plan of ~60g/hr, and compares well to her race earlier this year in Oceanside where she hit 58g/hr. This is, however, still below the 60-90g/hr recommendations of our Quick Carb Calculator. Scientific literature suggests that if Julie were to increase her carb intake to between 60-90g/hr or even higher, she may perform even better
      • Julie did manage to take on ~69g/hr on the bike, which is a decent amount and will have fueled her well. However, she felt mild GI distress when getting off the bike, and was nervous about having carb related stomach issues during the run so she sensibly tapered this amount down to ~42g/hour throughout the marathon
      • Julie rated her energy levels 10/10 for the swim and bike, dipping slightly during the run to a 7 which coincides with her drop in carb intake. Julie finished the run at a solid 10/10 for energy (perhaps as she knew a world championship title was heading her way!)


      • Overall, Julie had a great race and largely stuck to her hydration and fueling plan that she discussed pre-race with the PF&H Sports Science Team
      • When speaking to Chris the day before the race, Julie mentioned that she had high expectations for the race, saying “I’m here to win”. She backed this up in dominant fashion, showcasing how her confidence was well justified
      • Looking ahead to IM Alaska and the World Champs in Kona later this year, Julie may want to consider increasing her carb intake to be within the recommended ranges for a race of this length
      • Julie rated her overall race satisfaction a solid 10/10, saying “As I finished the day Age Group IRONMAN World Champion, I would say it went pretty damn well!”

    Key info

    Julie Dunkle

    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
    IRONMAN World Championships
    Utah, USA
    7th May, 2022
    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
    2,248m / 7,375ft
    Run Elevation
    431m / 1,414ft
    Total Elevation
    2,679m / 8,789ft

    Race conditions

    Weather Conditions
    Very Hot
    No Rain
    Min Temp
    21°C / 70°F
    Max Temp
    35°C / 95°F
    Avg Temp
    29°C / 84°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    I was feeling hydrated and never felt dizzy. Had to force myself to drink on the second half of the run
    Energy levels
    Swim and bike were 10/10, a couple of drops during the run, but back to 10/10 during the last couple of miles
    Toilet stops
    3 times on the bike roughly every hour
    GI comfort
    Mild GI distress getting off the bike, but this passed. 1 toilet stop at 25 miles on the run
    No cramping

    Julie's Thoughts

     Age group IM World Champion, I would say the day went pretty damn well!

    Julie's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake63913,17410,025641,314
    Per hour541,1208525
    Bike and Run
    Total intake60913,17410,025641,314
    Per hour571,2399436
    Total intake4137,3776,75001,093
    Per hour691,2261,1220
    Total intake1965,7973,275641,770
    Per hour421,25670914

    Data Confidence







    There is good confidence in the accuracy of the data reported. An athlete feels that the numbers closely reflect what they consumed despite a couple of estimations which may carry some degree of error. The majority of what was consumed is recorded to a high level of specificity (most volumes are known through the use of bottles brands quantities flavours). The numbers are very plausible and align with previous data recordings (if an athlete has collected data previously).

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