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Luke Henderson's scorecard

IM 70.3 Melbourne

Sunday 20th March, 2022

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 57g

    Carb per hour
  • 2,474mg

    Sodium per hour
  • 1,121ml

    Fluid per hour
  • 2,207mg/L

    Relative sodium concentration
  • 6.15mg/kg

    Caffeine per bodyweight
  • How Luke hit those numbers

    700ml x PH 1500 (2 Tablets)
    3 x Energy drink mix servings (21g carb each)
    1 x Coffee
    *** Review technique if drinking much at this point!
    2.3L x PH 1500 (Tablets)
    240ml x Plain water
    6 x Energy gel (25g carb)
    2 x Caffeine tablet (200mg caffeine)
    20 x PH Electrolyte Capsule
    2.15L x Plain water
    3 x Energy gel (25g carb)

    How Luke's hydration and fueling went...

      • After working closely with Luke to build a more aggressive fueling and hydration strategy for IRONMAN Western Australia in blisteringly hot conditions in 2021, we were looking forward to seeing Luke adjust the plan for a shorter day out at IM 70.3 Melbourne
      • The conditions in Melbourne were still warm (~21℃/69°F) but not as hot as Western Australia a few months prior, so the expectation was for Luke to somewhat dial down his fluid and sodium intake accordingly
      • With the recent birth of his son, Luke has done well to juggle his usual training schedule. Despite not getting in as much running training as he would have liked to, Luke performed exceptionally well at Melbourne to finish 7th in his age group, saying that he “couldn’t have done any better with his fueling and hydration”


      • As he did before IM Western Australia, Luke prepared for his high sodium losses by preloading with PH 1500 in ~700ml (24oz) to help maximise his blood volume and start well hydrated
      • In terms of fluid intake, Luke drank ~4.69L (165oz) of fluid in total over the whole race which broke down into ~1.15L/hr (39oz/hr) on the bike leg and ~1.4L/hr (50oz/hr) on the run. This is a high fluid intake, yet, in comparison to Luke’s full distance IM in WA this was ~300ml (10oz) less fluid per hour on the bike and ~200ml/hr less on the run
      • The conditions were cooler in Melbourne (average temperature 21°C/69°F compared to a warmer 28°C/82°F in Western Australia) and, the race was shorter in duration (70.3 vs. full distance IM), therefore a slightly less aggressive fluid intake was suitable
      • A high level of fluid replacement is necessary to keep up with the rate of his sweat losses. From previous data, we know Luke’s sweat rate can be over ~2L/hr (68oz/hr) in hot conditions.
      • In addition to his high fluid intake, Luke and the PF&H Team have discussed the fact that he should also adopt an aggressive approach to his sodium intake to help replace some of his huge losses
      • Luke had an Advanced Sweat Test and is an extremely salty sweater, losing 2,129mg of sodium per litre of sweat
      • During the bike leg, Luke drank a total of ~2.54L (86oz), predominantly made up of PH 1500 (~2.3L/77oz) and ~250ml/8oz plain water. Luke increased the strength of this drink by adding three PH 1500 tablets to each bottle. This meant the relative sodium concentration of each bottle was ~2250mg/L
      • On the run, Luke picked up ~10 cups of plain water (~200ml/6oz per cup) from the on-course aid stations, drinking ~2.15L (72oz) in total. Alongside this, Luke took four PH Electrolyte Capsules (which each contain 250mg of sodium per capsule) at every other aid station
      • As a result, Luke took on ~10,351mg of sodium in total across the race. This was an average of ~2,474mg/hr of sodium per hour which, when we account for his race intake, equates to a relative sodium concentration of ~2,207mg/L
      • Considering Luke’s high sweat sodium concentration, his sodium intake was impressive and will have helped him manage his losses throughout the race. Before working with PF&H, Luke had problems with cramping up during races, but he had no such issues in WA or Melbourne, which suggests that a more aggressive approach to his sodium replacement is making a difference
      • Despite the race being cooler than Western Australia, conditions were still humid, and Luke mentioned that he implemented cooling methods on the run, specifically “pouring water on his head”, which is a technique that the PF&H team advised him to use in his last race. Learn more
      • Overall, Luke didn’t feel that he would’ve changed anything in terms of his hydration strategy, rating it 10 out of 10


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • On the morning of race day, Luke consumed three energy drink mix servings (21g carb each), totaling a pre-race carb intake of ~63g. This is towards the bottom end of the recommended pre-race carb intake guideline of 1-4g of carb per kilogram of bodyweight between 1-4 hours before the race and usually triathletes opt to fuel with real foods ahead of a race of this duration (e.g porridge or toast). That said, the early race start may have impacted Luke’s ability to eat a substantial pre-race meal
      • Luke could consider having a ~30g dose of carbohydrate in the final 30 minutes pre-race, as the Quick Carb Calculator would recommend, to hit his bloodstream quickly and spare some glycogen stores for later in the race
      • During the race, Luke’s source of carbohydrate came solely from energy gels (25g carb each). On the bike, he took six gels and a further three on the run, meaning that he averaged ~57g of carb per hour over the race. This was a solid amount, but just below what we saw him achieve at IM Western Australia and just falling short of the recommended 60-90g/hr range
      • Breaking this down, on the bike leg Luke successfully met the recommendations and consumed ~74g/hr. Luke planned to take a gel every 20 minutes but after taking his fourth gel at 60 minutes he “felt a bit nauseous”. As a result, he delayed his next gel until 900 minutes which was the right thing to do but does suggest that he may benefit from increasing his intake through gut training during race simulation training sessions
      • All-in-all, Luke’s bike intake allowed him to go into the run well fueled and taper his intake to ~53g/hr during the half marathon
      • In terms of caffeine, Luke drank a coffee in the morning and had two caffeine tablets during the race (the first ~one hour into the bike and the second as he got off the bike). This resulted in a total caffeine intake of ~400mg (~6.1mg/kg body weight), towards the top end of the recommended range (3-6mg/kg) to enhance endurance performance


      • Overall, Luke maintained high energy levels throughout IM 70.3 Melbourne, rating his race satisfaction as 10 out of 10, although he mentioned that he would’ve wanted to go into the race with more running training under his belt
      • In terms of his hydration and fueling strategy, Luke thought that he “couldn’t have done any better”
      • Given his high sweat rate and very high sweat sodium concentration, Luke was again proactive in his strategy while adjusting to the shorter race duration and slightly cooler conditions to execute a brilliant strategy overall

    Key info

    Luke Henderson

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


    Overall Time
    Swim Time
    Bike Time
    Run Time

    Event information

    Middle distance
    IM 70.3 Melbourne
    Melbourne, Australia
    20th March, 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
    No Rain
    Min Temp
    17°C / 63°F
    Max Temp
    24°C / 75°F
    Avg Temp
    21°C / 70°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    I don't think I could have done any better
    Energy levels
    My energy was high throughout
    Toilet stops
    GI comfort
    I felt fine other than feeling slightly nauseous around 1 hour into the bike leg
    No cramping

    Luke's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake23710,3514,6904002,207
    Per hour572,4741,12196
    Bike and Run
    Total intake23710,3514,6904002,207
    Per hour652,8361,285110
    Total intake1625,2922,5404002,083
    Per hour742,4051,155182
    Total intake755,0592,15002,353
    Per hour523,4891,4830

    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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