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Julie Dunkle's scorecard

IRONMAN 70.3 Oceanside

Saturday 2nd April, 2022

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 58g

    Carb per hour
  • 773mg

    Sodium per hour
  • 396ml

    Fluid per hour
  • 1,952mg/L

    Relative sodium concentration
  • 3.21mg/kg

    Caffeine per bodyweight
  • How Julie hit those numbers

    700ml x PH 1500 (Tablet)
    700ml x Water (with amino acids)
    1 x Bowl of white rice
    1 x Mug of coffee
    1 x PF 30 Gel
    *** Review technique if drinking much at this point!
    2 x PF 30 Chews
    1.44L x Energy drink (22g carb)
    3 x Electrolyte capsule with caffeine (30mg caffeine)
    500ml x PF Carb & Electrolyte Drink Mix with PH 1000 (Tablets)
    0.5 x PF 30 Chews
    2 x PF 30 Gel
    60ml x Red Bull
    3 x Electrolyte capsule with caffeine (30mg caffeine)

    How Julie's hydration and fueling went...

      • Triathlete Julie Dunkle excelled at IRONMAN 70.3 Oceanside to claim 1st place in her age group (F55-59). Julie was stoked with the result and said post-race, “from start to finish, it was just amazing”
      • Julie has always suspected that her fluid and sodium losses were high and she confirmed those suspicions in 2019 when she started to get a handle on her individual losses by undergoing some extensive laboratory sweat testing to determine both her sweat rate and sweat sodium concentration in different conditions
      • As Julie’s net fluid and sodium losses can become significant, she has been developing a flexible hydration plan ahead of the IM World Champs in St George, Utah. Julie discussed her strategy with the Precision Fuel & Hydration Sports Science team before the race in order to gain some confidence in what she was planning to do


      • Julie’s Sweat Test confirmed that she’s a ‘salty sweater’, losing ~1,200mg of sodium per litre of sweat, so she made sure she went into this race optimally hydrated by preloading with ~500ml/16oz of PH 1500 the night before, as well as on the morning of the race
      • Julie had planned to drink two ~500ml/16oz bottles on the bike with PF 30 Drink Mix. However, this plan went out of the window when she got to her bike in T1 and found that one bottle was missing and the other was empty due to a leak! Consequently, Julie rode the first 18 miles of the bike leg with no fluid
      • As soon as she could, Julie strived at every opportunity to pick up the on-course hydration which provided her with an intake of ~679mg of sodium and ~540ml/17oz of fluid per hour. This meant that at the end of the bike leg, the relative sodium concentration (a measure of the sodium content vs. fluid volume) of her intake was ~1,257mg/L
      • During the run, Julie thought she had to play catch-up with her sodium losses because of the issues with her bike bottles, so she consumed a 500ml/16oz bottle containing two PH 1000 tablets and one serving of PF 30 Drink Mix, as well as three salt tablets. Therefore, the relative sodium concentration of her intake on the run was much higher (~3,738mg/L)
      • Given the relatively cool conditions at Oceanside, Julie could have reduced her sodium intake and / or dialled up her plain water consumption to account for the fact that her net sweat losses were unlikely to be too great. The fact she tolerated such high numbers bodes well for her hydration strategy ahead of the IM World Champs in St George, Utah, where conditions are likely to be much hotter and Julie’s net sweat sodium losses will therefore be considerably higher
      • Julie mentioned that she peed once during the bike leg indicating that she was well hydrated at that point. She didn’t pee again until finishing and she described her urine as “dark in color”, possibly indicating slight underhydration as a result of not drinking enough on the run. Julie could consider picking up additional plain water on the run, but in this race she felt her strategy was sufficient because her “sweat rate felt relatively low during this race”
      • After a bit of a wobbly start in terms of hydration on the bike, Julie’s ability to adjust to the circumstances quickly meant her performance wasn’t too affected by the loss of her two pre-prepared bottles


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Julie fueled well prior to Oceanside 70.3 by drinking a large coffee with coconut cream and a eating a bowl of white rice for breakfast to strategically maximise her glycogen stores and energy levels ahead of the tough race to come
      • In the 30 minutes before the race, Julie also had a PF 30 Energy Gel to receive a final ‘hit’ of carbohydrate and preserve her glycogen stores for later in the race
      • During the race, Julie’s carb intake came from a mixture of sources, including two-and-a-half packets of PF 30 Chews, two PF 30 Gels, and ~2L/34oz of carb drink mix, including ~500ml/16oz of PF Carb & Electrolyte Drink Mix. This totalled an intake of ~294g of carb during the race, averaging ~58g per hour
      • This is slightly below the 60-90g/hr recommendations of the Quick Carb Calculator for a race of this intensity and duration. When looking at the breakdown of her intake, Julie consumed ~56g/hr on the bike and ~65g/hr on the run, doing well to maintain a solid carb intake across both disciplines. Given the positive relationship between carbohydrate availability and endurance performance, a goal for Julie in future races (particularly the World Champs in May) would be to increase her carbohydrate intake on the bike, bringing it in line with what she can evidently tolerate on the run
      • Positively, Julie said that her gastrointestinal comfort was “amazing”, experiencing no issues, and rated her gut comfort a 10 (out of 10)
      • In terms of [caffeine](https://www.precisionhydration.com/performance-advice/nutrition/how-much-caffeine-should-athletes-use/, Julie had three salt tablets each containing 30mg of caffeine on the bike and another three during the run, taking one every 30 minutes. As well as this, Julie later had a “good swig” of an energy drink (~32mg of caffeine). This effective ‘drip feeding’ of caffeine resulted in a total caffeine intake of ~199mg (~3.2mg/kg bodyweight) which sits within the recommended caffeine range to enhance endurance performance (~3-6mg/kg)


      • From start to finish Julie thought her fueling and hydration strategy at IM 70.3 Oceanside “went great”. Despite losing her bottles on the bike and having to go without fluid for a time, Julie did really well to adapt and pick up what she could
      • In retrospect, given the cooler conditions and her own observation that she wasn’t sweating too heavily, Julie could have dialled down her sodium intake on the run
      • Julie consumed a solid amount of carbohydrate during the race, which could be pushed slightly higher in future races to meet the Quick Carb Calculator’s recommendations of 60-90g/hr for events of this duration and intensity

    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

    Middle distance
    IRONMAN 70.3 Oceanside
    California, USA
    2nd April, 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
    Bike Elevation
    829m / 2,720ft
    Run Elevation
    84m / 276ft
    Total Elevation
    913m / 2,995ft

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    14°C / 57°F
    Max Temp
    16°C / 61°F
    Avg Temp
    15°C / 59°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    I think it went great
    Energy levels
    My energy levels were amazing throughout
    Toilet stops
    One during and one after the bike
    GI comfort
    It was great, I had no issues at all
    No cramping

    Julie's Thoughts

     From start to finish it was just amazing

    Julie's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake2943,9032,0001991,952
    Per hour5877339639
    Bike and Run
    Total intake2643,9032,0001991,952
    Per hour5987744945
    Total intake1481,8101,440901,257
    Per hour5667954034
    Total intake1162,0935601093,738
    Per hour651,17431461

    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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