• After finishing the 2021 Marathon des Sables in 9th place, Pierre returned to the Sahara Desert for the 37th edition of the race and finished in a hugely impressive 6th place by going more than two hours quicker than his previous appearance
• Despite contending with sandstorms and the extreme temperatures which are synonymous with an event that’s known as ‘the hardest footrace on earth’, Pierre was extremely satisfied with his fuel & hydration strategy.…
• The best part of this for Pierre was playing a key role in his team, representing France, and becoming the first non-Moroccan team to win the event in 28 years
• The headline numbers on this page present calculations of Pierre’s best recollection of what he ate and drank whilst running, but we’ve also broken down how he went about recovering each day in the text below too

Hydration

• Each day at the MdS, Pierre and all other participants were given 1.5 litres of plain water to take out on course with them from camp, and an additional 3L at each checkpoint they passed through
• While this seems like a lot of weight to be running with, temperatures on the ground were reported to have soared to more than 50ºC’s (>122ºF) at some points, making replacement of fluid lost as sweat a priority
• Pierre knows from sweat rate testing that he loses ~1.5L (48oz) of fluid per hour in those conditions, so he took a proactive approach to replacing his sweat losses - he consumed ~1.47 litres of fluid per hour (48oz/h) during more than 23 hours of running, across six separate days
• Based on his experience of the 2021 race, Pierre felt he could increase his fluid intake in 2023 and that this would be to his advantage - he drank 59% more fluid during the 2023 edition than he did two years previously
• The other key factor Pierre had to contend with from a hydration point of view was electrolyte loss in his sweat over time, due to the importance of sodium in particular on factors like muscular contraction and fluid retention
• Having had a Sweat Test in 2021, Pierre knows that he loses 921mg of sodium per litre. He was also aware from his previous MdS appearance that his body tolerates both PH 1500 (Tablets) and PF 60 Energy Drink Mix (1000mg sodium per litre) well, in addition to the salt tablets which are handed to the competitors by race organisers
• We’d normally recommend someone with Pierre’s sweat sodium concentration (921mg/L) uses PH 1000 strength products, but having to carry all of his race nutrition for the week in his pack meant that the more highly concentrated PH 1500 tablets made sense from a weight and space-saving point of view
• TOP TIP: When running with our electrolyte tubes, stuff something soft into the cavity so that the tablets can’t shift up and down causing them to break
• Having significantly increased his hourly fluid consumption compared to 2021 it was crucial for Pierre to also increase his hourly electrolyte intake in order to maintain a relative sodium concentration which reflected his individual losses
• Knowing that this was important, Pierre did increase his sodium intake from ~1229mg per hour in 2021, to ~1961mg per hour in 2023, and in doing so achieved a suitable concentration of ~1336mg in each litre (32oz) of fluid he drank.
• Happily, other than feeling slightly dehydrated at the end of the Stage 4 (the longest day) and Stage 5 (marathon day), Pierre was incredibly pleased with his hydration strategy for this race

Fueling

Conclusions

• Pierre was incredibly satisfied with his performance in the 2023 MDS, giving subjective ratings of 10 (out of 10) for both his fueling and hydration strategy
• He reflected that the only thing he could have changed slightly would be to pack more ‘recovery’ drink mix powder to have in the evenings to avoid being as hungry when heading to bed
• It’s extremely impressive for someone to complete this race, let alone place in the top-10 and realise their ambition of claiming the team victory. Nailing his fuel and hydration throughout the week, Pierre was able to achieve all of the above and feel relatively good while doing so!