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Brett Halliwell's scorecard

IM 70.3 Swansea

Sunday 7th August, 2022

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 82g

    Carb per hour
  • 509mg

    Sodium per hour
  • 521ml

    Fluid per hour
  • 977mg/L

    Relative sodium concentration
  • 3.22mg/kg

    Caffeine per bodyweight
  • How Brett hit those numbers

    500ml x PH 1500 (Tablet)
    1 x PF 30 Caffeine Gel
    1L x Plain Water
    1 x Cup of Rice with Banana and Honey
    250ml x Black Coffee
    *** Try to avoid drinking too much at this point in the race!
    1L x PH 1500 (Tablets)
    2.66 x PF 90 Gel
    2 x PF 30 Caffeine Gel
    300ml x Plain water
    500ml x PH 1500 (Tablets)
    0.33 x PF 90 Gel
    640ml x Plain water
    240ml x Cola
    40ml x Red Bull

    How Brett's hydration and fueling went...

      • Brett suffered a hamstring injury a couple of weeks prior to toeing the line in Swansea and was a little apprehensive about how it would respond to a hard race
      • Fortunately he was able to swim and bike hard, before his pre-race fears came true and he was forced to run much slower than he’d have liked and allow the race to go on without him in the mix, sensibly not wishing to worsen his injury
      • Brett’s fueling and hydration on the bike was good, and would have set him up for a strong run performance, and he’s taken a lot of confidence from that


      • By preloading the night before and the morning of the race with 500ml/16oz of PH 1500, Brett will have optimised his blood plasma volume and reduced his cardiovascular strain as a result
      • Brett did drink a relatively large quantity of plain water the morning of the race (~1L/32oz), and therefore will have reduced the relative sodium concentration of his morning preload
      • As a habitual caffeine drinker, Brett had two black coffees with his breakfast which will have increased his alertness and reduced the perception of effort starting the race
      • During the bike, Brett’s 750ml/24oz bottle had two PH 1500 (Drink Mix) packets in. He also picked up ~300ml/10oz plain water from the on-course aid station to top up his fluid intake
      • This gave him a total fluid intake of ~1,050ml/35oz, with a relative sodium concentration of ~1,429mg per litre. Averaging just ~441ml/15oz per hour on the bike is quite low, but as temperatures were mild (13-20℃/55-68℉), and Brett’s self-perceived sweat rate is fairly modest, this will likely have replaced a good proportion of his sweat losses
      • On the run, Brett ran out of T2 with a 500ml/16oz bottle of PH 1500 which he held onto until kilometre eight, where after drinking ~350ml/11oz of it he discarded and switched to plain water and Coca Cola
      • In total, Brett drank ~1,270ml/43oz of fluid and ~766mg of sodium, which equates to a relative sodium concentration of ~603mg/L. Brett’s sweat sodium concentration is 573mg/L and therefore he did a solid job of replacing his losses


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • In true triathlete style, Brett had a whole margarita pizza and some garlic bread the night before the race, topping off two days of carb-loading. On race morning he ate a small bowl of plain rice with some banana and honey mixed in to further top up his glycogen stores
      • Brett planned to take a PF 30 Caffeine Gel within 20 minutes of the start, but as the race was delayed this ended up being ~45 minutes before the gun went off
      • Whilst the caffeine will still have given Brett a boost in performance, his blood glucose levels won’t have been optimised and would likely have been decreasing by the time he actually started
      • By adding three PF 90 Gels into his 500ml/16oz bottle along with two PF 30 Caffeine Gels in his bento box, Brett hit an impressive ~127g of carb per hour on the bike. This is slightly over what the science suggests is optimal for endurance performance, and perhaps Brett’s gut wasn’t fully absorbing this quantity of carb
      • Furthermore, his stomach felt a bit full heading onto the run so backed off the carb. In addition to feeling full, as he stepped off the bike and began running, a niggling hamstring injury resurfaced and put an end to his competitive ambitions for the day
      • Brett continued to back off the carb as his pace dropped, and he felt he no longer required an aggressive fueling strategy. In the end, he took just ~61g of carbs during the run, averaging ~40g/h


      • In all, Brett was “pretty pleased” with his race in Swansea, showing he could mix it with the front guys on the bike, and but for a niggling injury he was prepared to run hard too
      • With an average carb intake of ~82g/h across the whole race, Brett’s gut training in recent months is paying dividends, but could benefit perhaps by slightly reducing his intake on the bike so he doesn’t experience any stomach discomfort in the early stages of the run
      • Brett added that despite not having the race he planned, he’s in good spirits heading into another block of training, thanking himself that he backed off and didn’t worsen his hamstring injury

    Key info

    Brett Halliwell

    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
    IM 70.3 Swansea
    Swansea, Wales
    7th August, 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
    900m / 2,953ft
    Run Elevation
    25m / 82ft
    Total Elevation
    925m / 3,035ft

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    13°C / 55°F
    Max Temp
    20°C / 68°F
    Avg Temp
    18°C / 64°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    I didn't take on too much fluid on the bike as temperatures were mild, felt a bit thirsty heading onto the run so maybe over did the sodium a little
    Energy levels
    No dips at all, ran the last ~3k with Kat Matthews and was able to pick up the pace no problem
    Toilet stops
    GI comfort
    Stomach felt really good the whole way
    No cramping

    Brett's Thoughts

     My hamstring injury reared it's ugly head on the run, so I decided to run easy and not make it worse. Up until that point I was feeling really good so I can take a lot of positives from this race

    Brett's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake3642,2662,320232977
    Per hour8250952152
    Bike and Run
    Total intake3642,2662,320232977
    Per hour9357859259
    Total intake3031,5001,0502001,429
    Per hour12762944184
    Total intake617661,27032603
    Per hour4049982821

    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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