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Joe Wenman's scorecard

Portsmouth Coastal Waterside Ultra

Sunday 19th December, 2021

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 54g

    Carb per hour
  • 314mg

    Sodium per hour
  • 417ml

    Fluid per hour
  • 754mg/L

    Relative sodium concentration
  • 3.95mg/kg

    Caffeine per bodyweight
  • How Joe hit those numbers

    500ml x PH 1500 (Tablet)
    1 x Black coffee
    1 x Bowl of porridge with berries, pecan and chia seeds
    1 x PF 30 Gel
    1L x PH 1000 (Tablets)
    1 x PH Electrolyte Capsule
    4 x PF 30 Gel
    500ml x Plain water
    2 x Energy gel with caffeine (22g carb, 150mg caffeine)
    200ml x Cola

    How Joe's hydration and fueling went...

      • Precision Fuel & Hydration Sweat Test Officer and running coach Joe Wenman ended his season on a high with a 6th place finish at the Portsmouth Coastal Waterside Ultra
      • Pre-race, Joe refined his well-thought out Fueling & Hydration plan with the help of Sport Scientist Emily, increasing his confidence going into the race just before Christmas
      • Having never completed a flat race before, Joe was interested in doing something different and thought this 50km with only 100m/328ft elevation was the perfect opportunity. Prior to this race, both his marathon and 50km PB were set on an 80km course with 2899m/9511ft elevation
      • After finishing the race in a new 50km PB time of 4 hours and 4 minutes, Joe said “I was chuffed to keep up with the flat-landers to finish with a good result and a whole bunch of personal records”


      • Joe was able to weigh himself both before and immediately after the race to help us quantify his total volume of sweat losses (learn more)
      • Joe finished the race with a -2.88% change in bodyweight. Although it has been widely debated how much dehydration individuals can tolerate before performance suffers, we know it can be highly individual. The 2% rule around dehydration is recognised to be a myth within Sports Science which originated from old scientific studies that purposely, and aggressively, dehydrated athletes ahead of exercise and saw performance, unsurprisingly, suffer as a result. It’s now more widely accepted that endurance athletes may finish 2-4% dehydrated without any obvious impediment to performance
      • A contemporary theory is that well-trained athletes are more accustomed to these levels of dehydration (as a result of their high volume of training) and their performance is less affected
      • From the data Joe collected, we were able to estimate his sweat rate. In total Joe drank ~1.7L/57oz and lost 2.3kg (5lbs) in bodyweight, which suggests his total sweat loss was ~4L/135oz and equates to an average sweat rate of ~1L/34oz per hour. It’s important to recognise in an event of this duration that this sweat rate is an estimate, and that not all bodyweight lost will have been from sweat losses (some may have been glycogen metabolism or respiratory losses)
      • Joe drank an average of ~417ml/hr (14oz/hr), so we can see that he was replacing just under half of his estimated losses throughout the race. Taking into account the cooler conditions and the race duration, this is a decent level of replacement. That said, replacing a little more fluid (closer to ~500ml/hr) may have aided Joe’s performance
      • Joe rated his hydration strategy as 7 out of 10, saying “it was perfect for the first half, but if the race had been longer I would have struggled”. This ties in with what we see in his numbers; his fluid intake was adequate for the distance but any longer and Joe may have struggled as his degree of dehydration became more substantial
      • We can estimate Joe’s overall sweat sodium losses because we know from his Advanced Sweat Test that he loses 1,208mg of sodium per litre of sweat and he was losing ~1 litre of sweat per hour, so he was losing ~1,208mg of sodium per hour. In terms of Joe’s sodium intake, he consumed ~314mg/hr which meant the relative sodium concentration of his intake was ~754mg/L. It’s feasible that consuming a bit more sodium may have been beneficial, but we know that 100% replacement, especially in cooler conditions, isn’t necessary
      • Joe said he chose to listen to his body and didn’t take on as many electrolyte capsules as he had planned because he didn’t feel he needed them towards the end of the race. He was happy with this strategy and didn’t experience any cramping during the run


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Before an 8:00am race start, Joe had a solid high carbohydrate meal of porridge with goji berries, pecans, chia seeds and syrup, as well as a PF30 Gel in the final 15 minutes, to top off his glycogen stores
      • On average, Joe consumed ~54g of carb per hour during the race which kept his energy levels up throughout the run. He rated his energy levels as 8 out of 10 and said he only felt a decline just prior to the finish
      • Joe may benefit from trying to increase his carb intake above 60g/hr; the Quick Carb Calculator would recommend he ingest 60-90g/hr over the course of the race. This is because evidence suggests that a higher carb intake can optimise performance as long as the amount consumed doesn’t cause stomach problems. Therefore, Joe may want to undertake some gut training, by gradually increasing his carb intake in practise, to develop his tolerance to a greater carb intake
      • Joe had a solid plan, which included a range of energy gels and bars, with the aim to eat at least every 10km. This was a good strategy as it helped ensure that he didn’t go for a sustained period of time without fueling during the race
      • Unfortunately, around 42km into the run, Joe was sick. He said “I felt sick for 5 minutes but after throwing up for a short amount of time, I was alright again.” He put this down to the point in the race, because towards the end of the marathon he had upped his pace significantly to get a marathon PB
      • Although he wasn’t severely sick, throwing up could have played a part in why his energy dipped in the latter stages of the race, as he would have lost some of the carbohydrate in his stomach before it was absorbed
      • Joe’s total caffeine intake during the race was ~316mg and he also pre-caffeinated with a strong coffee in the morning. This intake is within the recommended caffeine dose to enhance endurance performance due to its effects at reducing perceptions of effort (3-6mg of caffeine per kilogram of bodyweight)


      • Joe was “happy with the result” at the Portsmouth Coastal Waterside Ultra after meeting his goal to achieve both marathon and 50km personal bests! Therefore, he rated his race satisfaction as 8 out of 10
      • He has many races lined up next year, including the Manchester Marathon, Endurance Life Pembrokeshire Ultra and Centurion South Downs Way 100 in June. For those events, Joe may benefit from trying to increase his hourly carb intake to see if that helps his performance, while he will want to increase his sodium intake in warmer race conditions

    Key info

    Joe Wenman

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


    Overall Time
    Bodyweight change

    Event information

    Portsmouth Coastal Waterside Ultra
    Portsmouth, England
    19th December, 2021
    Total Distance
    50.0km / 31.1mi
    Total Elevation
    100m / 328ft

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    5°C / 41°F
    Max Temp
    7°C / 45°F
    Avg Temp
    7°C / 45°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    Energy levels
    Energy levels were really good most of the race but started to decline in the last few kilometres
    Toilet stops
    GI comfort
    I threw up once around the marathon mark but was completely fine after
    No cramping

    Joe's Thoughts

     Before this race, my marathon and 50k PB were set on an 80k course with 9510ft of elevation, so I was chuffed to keep up with the flat-landers and finish with a good result and a whole bunch of new personal records

    Joe's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake2201,2811,700316754
    Per hour5431441777

    Data Confidence







    There is a high level of confidence in the accuracy in the data. The numbers presented are believed to be a very close reflection of reality. There may still be one or two estimations made in the data (an inescapable part of field data) but there is reason to believe that these are accurate and that possible error has been kept to a minimum. It is data that has been collected and recalled as accurately as is possible given the uncontrolled settings/circumstances.

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