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Line Thams' scorecard

IM 70.3 World Championship

Saturday 18th September, 2021

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 67g

    Carb per hour
  • 396mg

    Sodium per hour
  • 853ml

    Fluid per hour
  • 464mg/L

    Relative sodium concentration
  • 4.97mg/kg

    Caffeine per bodyweight
  • How Line hit those numbers

    1L x PH 1000 (Tablets)
    2 x Pieces of bread with nutella and banana
    1 x Energy gel (25g carb)
    *** Tip: For sea swims, put a bottle of water at T1 to rinse your mouth out
    500ml x PH 1000 (Tablets)
    500ml x PH 1500 (Tablets)
    1.3L x Plain water
    500ml x Additional fluid in mixed drinks
    5 x Energy gel (25g carb)
    2 x Energy gel (25g carb)
    570ml x Plain water
    1 x Energy chew packet with electrolytes (46g carb, 300mg sodium)
    270ml x Cola
    270ml x Red Bull

    How Line's hydration and fueling went...

      • Line had a tough race at the IM 70.3 World Champs, coming in 19th in a time of 4 hours 34 minutes. She felt her second attempt at IRONMAN 70.3 distance racing was “poor compared to my first” and that this was in part due to a “tough lead up” to the race
      • She rated her overall race satisfaction as a low 2 out of 10, but she actually felt she stuck to her fueling plan in this race far better than during her debut IM 70.3


      • Line preloaded with PH 1000 tablet in 1L of water. Having some sodium pre-race will have helped her start hydrated but we would recommend she uses a stronger PH 1500 in 500ml (16oz) water going forward.
      • Having only one tablet in additional water dilutes the concentration of sodium she is taking on board. Drinking one PH 1500 tablet in 500ml/16oz would allow her to start the race optimally hydrated, with maximal blood volume.
      • Line consumed around ~396mg/hr sodium and ~853ml/hr fluid which equates to The relative sodium concentration of Line’s race intake was ~464mg/L. We don’t yet know Line’s sweat sodium concentration so it’s hard to determine if she was replacing an adequate amount of what she was losing in her sweat, but this is generally on the more low-to-moderate sid
      • As a first step, we would recommend she looks to increase her sodium intake slightly (especially in warm or hot conditions) simply by mixing each tablet in 500ml/16oz of water to avoid diluting the concentration of the PH electrolytes she’s consuming
      • On the same note, Line’s fluid consumption could possibly also have been slightly reduced from ~853ml/hr, which is quite a high volume of fluid. Decreasing her overall fluid intake slightly would increase the relative sodium concentration she’s consuming. Line did mention there were portions of the run where she felt she had lots of fluid on board, supporting the recommendation that fluid intake was on the high rather than low side for the conditions
      • We’re hoping to Sweat Test Line in November which will help us refine her hydration strategy for future races


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Line enjoyed a solid pre-race intake, consuming a breakfast high in carbs and having an energy gel just prior to the swim start. This is ideal to make sure her fuel stores were well topped up for the start of the race
      • Line consumed ~67g/hr carb during the race which is a solid intake and well within the Quick Carb Calculator recommendation of 60-90g/hr, with Line taking in ~73g/hr on the bike and ~65g/hr on the run
      • These carb numbers offer a great basis for Line to potentially even increase her intake towards the higher 90g/hr range with some gut training during key sessions as evidence suggests this can be beneficial for performance and recovery
      • Line rated her gastrointestinal comfort as 8 out of 10 but did say that on the last 1km of the run she started to feel a bit of GI distress. She also explained that she had low energy levels but felt that this was due to a sub-optimal build-up to the race, rather than anything nutrition-wise
      • Line consumed ~308mg of caffeine (~67mg/hr). The recommended caffeine dose for performance is 3-6mg per kilogram of bodyweight. Line weighs 62kg and therefore took a moderate dose towards the top end of the range for someone of her bodyweight (186-372mg)


      • Overall, Line executed her hydration and fueling plan reasonably well considering it was only her second ever race over the IM 70.3 distance
      • Going forward, Line’s upcoming Sweat Test will give us a greater insight into her sweat sodium concentration and help refine her hydration strategy
      • In broader terms, she could look to push her carb intake up further which could benefit her performance. When encountering similar race conditions in the future we would also recommend that she slightly reduces her fluid intake, mixing tablets as advised to not dilute the relative sodium concentration of PH electrolytes

    Key info

    Line Thams



    Overall Time
    Swim Time
    Bike Time
    Run Time

    Event information

    Middle distance
    IM 70.3 World Championship
    St George, Utah, USA
    18th September, 2021
    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
    835m / 2,740ft
    Run Elevation
    833m / 2,733ft
    Total Elevation
    1,668m / 5,472ft

    Race conditions

    Weather Conditions
    Min Temp
    20°C / 68°F
    Max Temp
    30°C / 86°F
    Avg Temp
    25°C / 77°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    Energy levels
    Low energy levels but I do not put this down to my nutrition
    GI comfort
    On the last 1km of the run I started to feel a bit of GI discomfort
    No cramping

    Line's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake3081,8153,910308464
    Per hour6739685367
    Bike and Run
    Total intake2831,7963,910308459
    Per hour7044296176
    Total intake1791,3912,800200497
    Per hour735641,13581
    Total intake1044051,110108365
    Per hour6525369468

    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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