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Pierre Meslet's scorecard

Manchester Marathon

Sunday 3rd April, 2022

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 113g

    Carb per hour
  • 366mg

    Sodium per hour
  • 290ml

    Fluid per hour
  • 1,260mg/L

    Relative sodium concentration
  • 3.57mg/kg

    Caffeine per bodyweight
  • How Pierre hit those numbers

    250ml x PH 1500 (Tablet)
    1 x Medium bowl of porridge
    1 x Small croissant with nutella
    1 x Slice of toast (brown) with butter
    1 x Mug of hot oat milk
    1 x Energy Gel with caffeine (30g carb, 50mg caffeine)
    500ml x PH 1500 (Tablets)
    3 x PF 30 Gel
    1 x PF 30 Chews
    250ml x Plain water
    2 x Energy gel with caffeine (30g carb, 100mg caffeine)
    1 x Energy drink mix (79g carb)

    How Pierre's hydration and fueling went...

      • The Precision Fuel & Hydration team first worked with French ultrarunner Pierre Meslet in 2021 when he attended a Sweat Testing workshop in London prior to competing in the Marathon Des Sables, a seven day multi-stage desert race in which he finished 9th. Since then, Pierre has been targeting faster, shorter distances with the Manchester Marathon being a target race
      • Pierre’s aim for Manchester was to run below two-and-a-half hours but unfortunately suffered a tear in his calf just four weeks out from race day. This meant his final weeks of preparation were spent focusing less on high-quality preparatory sessions and more on whether or not he would be able to sustain a good pace for the duration of the marathon
      • Despite the less than optimal race build-up, Pierre had a great day out in Manchester, setting a new marathon personal best of 02:35:25 and finishing 24th in his age-group (M35-39)
      • Pierre felt that the disruption caused by managing injury during the few weeks before the race meant that he didn’t plan his fueling and hydration strategy for this race as well as he should have. But he still consumed an impressive amount of carbohydrate whilst suffering no GI issues, and took enough fluid and sodium to see him through the race without any major detriment


      • Pierre felt his hydration strategy left plenty of room for improvement. He chose to run with a 500ml/16oz soft flask which he finished around the half-marathon mark and then picked up one small bottle of plain water to refill it. Pierre estimated that in total he drank ~750ml/24oz over the course of the race, averaging ~290ml/10oz per hour
      • Whilst this is a relatively low fluid intake (especially for Pierre who we’ve seen consume in excess of 1L/32oz per hour when racing in the heat at the MdS), it’s important to note that the conditions in Manchester were cool on the day (~9ºC/48ºF). Therefore, Pierre’s sweat losses would be expected to be lower and as a result his fluid intake should fall in line with these lower losses
      • That being said, Pierre did feel like he required a bit more fluid during the race, estimating a further ~300-500ml (10-16oz) would have been optimal. Within 20-minutes of finishing the marathon, Pierre had drunk 500ml/16oz of a recovery drink mix, after which he felt much better; which would suggest that taking on some more fluid was necessary
      • Similar to his fluid intake, Pierre felt as though he underdid his sodium intake towards the end of the race, commenting that he “didn’t carry enough sodium and should have carried some electrolyte capsules
      • Pierre preloaded before the race with PH 1500 as per recommendations and carried a sodium-rich drink mix with him during the first half of the marathon, which is a lot more than most athletes would do. In total, he consumed ~945mg of sodium (~366mg/h), which when we account for the fluid he drank, equated to a relative sodium concentration (a measure of sodium to fluid ratio) of ~1,290mg/L
      • When we account for Pierre’s sweat sodium concentration (921mg/L), the relative sodium concentration of his intake was very good. Where Pierre may have improved his strategy was by drinking a greater absolute volume of fluid (and increasing his sodium intake to keep the relative sodium concentration the same), particularly towards the end of the race
      • Pierre did experience some twinges of cramp from ~35km but managed to push through until the finish. Rather than this being directly associated with his sodium intake, Pierre suspects that this was a result of a lack of specific conditioning in the final weeks due to his injury
      • Pierre’s recovery was slower and poorer than normal, rating it only 3 (out of 10), which he speculated may also be linked to his injury and lack of conditioning


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Approximately three hours before the race start, Pierre fueled well by eating a combination of carb-rich foods, including a small bowl of porridge, a croissant and a slice of brown toast. He also consumed a final caffeinated energy gel in the 30 minutes before the race start
      • Whether an athlete chooses to have a final pre-race gel just before race start comes down to personal preference but it can be an effective tactic to spike blood glucose levels and increase carbohydrate availability in the early stages, potentially sparing some of the body’s glycogen stores for later (learn more)
      • Across the race, Pierre used a combination of energy gels; three standard PF 30 Energy Gels and two caffeinated gels (100mg caffeine). In addition to this, he took one PF 30 Energy Chew (Mint & Lemon) and carried a 500ml/16oz soft flask containing a sachet of carb-rich drink mix (79g per serving)
      • This, coupled with the energy gel he took just before the race start, meant that Pierre consumed an average of ~113g of carbohydrate per hour. We know from working with Pierre before that he can tolerate carbohydrate intakes of more than 90g/h but this is the first time we’ve seen him consume above 100g per hour
      • We’re seeing a growing number of athletes who are able to consume in excess of 90g/h, but it’s important to note that these athletes undergo extensive gut training to become accustomed to this. Pierre used his training sessions to fuel with increasing amounts of carbs in the weeks leading up to the marathon and he was trialling his race day fueling strategy in race-simulation training runs. As a result, Pierre rated his gastrointestinal comfort on race day as 10-out-of-10, saying he “had no issues at all”
      • For future marathons, Pierre reflected that he would stick to using gels as they were easier to consume when he found chewing more difficult due to having a dry mouth in the latter stages of the marathon


      • Despite a less than optimal race build-up as he attempted to manage his calf tear, Pierre had a good race at the Manchester Marathon and clocked a new personal best. With his focus being on whether he could rehab his calf to a point where he would race, Pierre felt he didn’t prepare his fueling and hydration strategy for the marathon as well as he should have, falling short on fluid specifically, and felt that his lack of specific conditioning in the weeks prior affected his performance
      • Overall though, Pierre had a great run given the circumstances, hitting very high carbohydrate numbers (>100g/h), with no gut issues or drops in energy levels, which bodes well for future marathons when the run-up to the race has hopefully been slightly smoother

    Key info

    Pierre Meslet

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


    Overall Time

    Event information

    Manchester Marathon
    Manchester, England
    3rd April, 2022
    Total Distance
    42.2km / 26.2mi
    Total Elevation
    54m / 177ft

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    8°C / 46°F
    Max Temp
    10°C / 50°F
    Avg Temp
    9°C / 48°F

    Athlete feedback

    Race Satisfaction
    Hydration rating
    I would have been happier with ~300-500ml (10-16oz) more fluid
    Energy levels
    GI comfort
    No issues at all
    Twinges but not full-on cramps

    Pierre's Thoughts

     Very pleased with a PB and how I raced but I was aiming for a little faster

    Pierre's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake2919457502501,260
    Per hour11336629097

    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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