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Stuart Hayes' scorecard

World Sprint Championships

Saturday 15th July, 2023

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 57g

    Carb per hour
  • 141mg

    Sodium per hour
  • 281ml

    Fluid per hour
  • 500mg/L

    Relative sodium concentration
  • 200mg

    Total caffeine
  • How Stuart hit those numbers

    1 x 3 Egg omelette
    1 x Serving of mixed fruit
    8 x Rice cakes
    2 x Protein Balls
    1 x PF 30 Caffeine Gel
    *** Review technique if drinking much at this point!
    300ml x PH 500 (Tablets)
    1 x PF 30 Caffeine Gel

    How Stuart's hydration and fueling went...

      • 2012 Olympian Stuart is an English triathlete who, after retiring in 2015, returned to international competition in 2023 to compete in the World Sprint Championships in Hamburg alongside his wife Michelle Dillon
      • In an event which would be finished in less than an hour and a half, the key thing from a fueling and hydration perspective is the preparation for the race
      • Stuart was pleased with his performance, especially given the fact that he'd severely injured both calves and wasn’t yet back at full run fitness


      • Flying over from the UK, Stuart knew that it would be warmer in Hamburg than he had been experiencing at home. And with temperatures reaching 23ºC (73ºF) on the day, starting optimally hydrated was paramount
      • To do this, Stuart drank a 500ml (16oz) serving of PH 1500 both the night before and morning of the race, in order to boost his blood plasma volume ahead of the midday start time
      • During a sprint triathlon, Stuart is only on the course for just over an hour and isn’t personally losing enough fluid via sweat to impact his performance negatively
      • Despite this, he still chose to sip on some PH 500 while on the bike. This can be a satisfying tactic to clear the mouth out after swimming and help with perceived cooling if the bottle has been chilled beforehand
      • When on the 20 minute run, Stuart didn’t drink anything, but did dump water over his head in order to cool down


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Just like he ensured he arrived at the startline optimally hydrated, Stuart carb loaded to make sure that he started the race with the glycogen stores in his muscles and his liver fully stocked and ready to provide energy to his working muscles
      • In order to do this and not overeat, Stuart had to reduce the proportion of protein and fibre slightly in his diet the day before the race. Instead, replacing those types of foods with things like corn cakes, of which he ‘ate as many as he could possibly stomach’
      • An important final step in Stuart’s preparation for this race was his PF 30 Caffeine Gel within the last 30 minutes before start time. Not only did the carbohydrate content increase the available blood glucose his muscles had to use at the start, but it also enabled him to reap the performance benefits associated with caffeine
      • The timing of this caffeine gel was excellent, as it takes ~45 minutes to peak in the bloodstream, meaning he’d be finishing the bike and moving onto the run just as it was taking full effect
      • Stuart then had one more PF 30 Caffeine Gel while on the bike to top off his energy and give him an average carb intake of ~57g per hour
      • Typically, the scientific recommendations would suggest that during events up to an hour long, athletes won’t benefit from fueling more than 30g/h a huge amount, and so it may be worth Stuart considering using a small amount of PF 60 Energy Drink Mix and save some time by not having to sit up and open the gel packet


      • Stuart approached this race with optimal fueling and hydration preparation and was pleased with how he performed, especially as making it to the end of the run following his return from injury was the main aim.
      • After this race, Stuart told us that he’s already looking forward to the World Champs in Malaga in 2024, where his training build intensity can be a bit higher than this time around where he was hampered by injury

    Key info

    Stuart Hayes



    Overall Time
    Swim Time
    Bike Time
    Run Time

    Event information

    Short course
    World Sprint Championships
    Hamburg, Germany
    15th July, 2023
    Swim Distance
    0.8km / 0.5mi
    Bike Distance
    20.0km / 12.4mi
    Run Distance
    5.0km / 3.1mi
    Total Distance
    25.8km / 16.0mi

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    22°C / 72°F
    Max Temp
    23°C / 73°F
    Avg Temp
    22°C / 72°F

    Stuart's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake61150300200500
    Per hour57141281188
    Bike and Run
    Total intake31150300100500
    Per hour35170340113
    Total intake31150300100500
    Per hour56273545182

    Data Confidence







    There is some confidence in the quantities and brands of products consumed but the data may lack specifics (e.g. volumes specific flavours). A high number of estimations have been made and the room for error is moderate-high. There may also be the possibility that some intake has been grossly over- or under-estimated.

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