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Toby Robinson's scorecard

Tokyo Olympic 10km Qualifier

Sunday 20th June, 2021

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 89g

    Carb per hour
  • 4mg

    Sodium per hour
  • 280ml

    Fluid per hour
  • 15mg/L

    Relative sodium concentration
  • 0mg/kg

    Caffeine per bodyweight
  • How Toby hit those numbers

    500ml x Electrolyte tablet (339mg sodium)
    500ml x Energy drink mix (80g carb)
    1 x Banana
    1 x Coffee
    1 x Caffeine gum
    570ml x Energy drink mix (80g carb)

    How Toby's hydration and fueling went...

      • Toby Robinson, a GB Open Water Swimmer, is one to watch in years to come. Competing at the Tokyo 2021 Olympic 10km Qualifiers, he narrowly missed out on going to the Games. Toby swam an extremely quick 10km race in a time of 2 hours and 2 minutes at an average pace of 12:13 min/km
      • The race was held in Setubal, Portugal, in relatively hot ambient conditions (20℃/68°F) with sea temperatures of ~18℃/64°F. This can prove challenging in terms of thermoregulation when swimming, but Toby coped extremely well to finish 3rd overall


      • Pre-race, Toby drank 500ml/16oz of water mixed with electrolyte tablets that contained 339mg of sodium. We would recommend that Toby preloads before the 10km by drinking a stronger electrolyte solution pre-race, for example PH 1500. Preloading with a high-sodium electrolyte drink before the race will have made sure he was starting optimally hydrated with maximal blood volume. Especially with the demands of open water swimming, hydrating can be difficult, so prioritising good hydration pre-race is crucial
      • Over the entire race, Toby drank a total of ~570ml (20oz) of fluid which equates to an average of ~280ml/hr (~9oz/hr) per hour. Without data on Toby’s sweat rate, it’s hard to determine whether this adequately replaced his sweat losses in the hot conditions (20℃/68°F). It’s likely given the warm conditions, Toby’s high work rate, and the limited opportunities to drink that his sweat rate outstripped his fluid intake by quite some margin
      • To some degree this is just the nature of open water swimming and it’s fair to say that Toby did a good job at drinking given the circumstances
      • One area that Toby could improve on is his electrolyte intake during the race (specifically sodium). Sodium is the electrolyte lost in the biggest proportions of our sweat and it plays a fundamental role in fluid balance in the body. In total, he only consumed ~9mg of sodium. This is because he drank solely an energy drink mix which was almost devoid of sodium
      • In hot conditions and racing at a high intensity, we would recommend that Toby ingests a larger amount of sodium, such as our PF 30 Drink Mix to increase the relative sodium concentration of his intake and replace a greater amount of his sweat sodium losses whilst still meeting his carbohydrate needs
      • Toby does believe there is definitely room for improvement when it comes to his hydration, rating his hydration plan a 6 out of 10


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Toby carb loaded leading up to the race, this involved eating a greater proportion of carbohydrate in the 2-3 days before
      • Toby’s pre-race fueling and hydration varies depending on each race’s start time, whether it be an 8am, midday or late afternoon race. As the qualifier had an afternoon start of 4pm, he ate a carb heavy breakfast, snacks, and drank an energy drink mix (80g carb) throughout the day and then consumed a final banana within the last hour
      • This is a nutritious pre-race meal, which was very carb heavy, topping up his glycogen stores ahead of the race. The general recommendation to maximise endurance performance is to consume between 1-4g carb per kilogram of bodyweight 1-4 hours before the race
      • During the 10km swim, Toby fed three times from a feeding pontoon where he flipped onto his back and attempted to drink 250ml of energy drink (80g carb) each time
      • Fuelling can be particularly challenging in open water swimming where you have approximately 4 seconds to feed or else you risk losing your position in the race
      • Toby believes he managed to consume ~75% of each drink, closer to around ~190ml each feed which resulted in an average carb intake of ~89g/hr
      • For a race of this duration and intensity, The Quick Carb Calculator would recommend 30-60g of carbohydrate during the race. Toby surpassed the recommendation by a big margin, but this was tolerable for him and due to the relationship between higher carb intake and performance, this was a great amount of carb to ingest. Toby rated his overall energy levels as 9 out of 10
      • Due to having to feed fast, Toby rated his GI comfort at 7 out of 10 and said that “the only time I feel any stomach discomfort is when taking on a feed due to the high amount of fluid and carb I am drinking within such a short period of time”
      • Toby took some caffeine 30 minutes before racing with a large coffee and some caffeine gum (~100mg) which can help to improve alertness, reduce perceptions of effort and delay fatigue
      • After the race, Toby mentioned his recovery was around a 6 out of 10, and said “it often takes me about a week to fully recover from a 10k marathon race with symptoms such as muscle soreness and exhaustion”


      • Toby raced extremely well in the qualifiers for the Tokyo Olympics, making the most of every opportunity to drink and ultimately having a great carbohydrate intake which fueled a great performance
      • In future, Toby could benefit from increasing his sodium intake during the race to be more in line with his sweat sodium losses and to help the body maintain better fluid balance. Being more proactive with his hydration may also help aid better recovery following tough races
      • Toby will continue training hard and competing, having his heart set on qualifying for the 10km at the Paris Olympics in 2024

    Key info

    Toby Robinson



    Overall Time

    Event information

    Tokyo Olympic 10km Qualifier
    Setubal, Portugal
    20th June, 2021
    Total Distance
    10.0km / 6.2mi

    Event conditions

    Weather Conditions
    No Rain
    Min Temp
    20°C / 68°F
    Max Temp
    21°C / 70°F
    Avg Temp
    20°C / 68°F

    Athlete feedback

    Hydration rating
    I am happy with my hydration strategy before races but I feel like there is room for improvement during the race
    Energy levels
    Toilet stops
    GI comfort
    I often feel stomach discomfort when taking on a feed due to the amount of liquid I am drinking within such short periods of time
    No cramping

    Toby's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake1809570015
    Per hour8942800

    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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