Nick Harris-Fry
London Marathon
LondonOtherNick's headline numbers
Nick's strategy
Fueling
T - 1-4hrs: Ate a carb rich meal (Low in fat & fibre)
T - 15mins: Took in a final dose of carb
"Excluding the usual marathon fatigue"
Nick pre-fueled sufficiently with a carb-rich breakfast and some energy drink right before the race to top up his energy stores and kickstart his blood sugar. Despite consuming some energy gels and drinks during the race itself, Nick averaged ~50g/h of carbohydrate, which is lower than the scientific recommendations for a race of this distance and intensity. This is largely due to the fact that he experienced some GI discomfort and consequently had to limit his fueling until his stomach settled. Ahead of future races, we would recommend Nick undergo structured gut training during his longer and higher intensity sessions to ensure he can comfortably tolerate higher volumes of carbohydrate to maintain his energy levels.
Hydration
Taking on board an appropriate amount of fluid and sodium is essential to maintaining blood volume and supporting the cardiovascular effort needed to perform on race day.
Whilst the absolute amount of sodium and fluid consumed per hour is important, it’s critical to consider these in relation to each other. This is known as 'relative sodium concentration' and it’s expressed in milligrams per litre (mg/L). How much sodium you’re taking in per litre of fluid is more important than the absolute amount taken in per hour.
Nick716mg/L
Nick has been Sweat Tested to dial in his hydration plan
Sweat sodium concentration (mg/L) is largely genetically determined and remains relatively stable. Knowing how salty your sweat is enables you to replace a good proportion of your sweat losses, which can range from 200-2,000mg/L.
Whilst Nick's losses are on the low side, getting his hydration strategy right is still important if he wants to perform at his best.
Learn moreT - 60mins: Drank ~500ml of strong electrolyte drink
"I never felt thirsty during the race so I think I managed my hydration well."
Given the mild temperatures, it's likely that the ~353ml/h of fluid Nick consumed was sufficient to stay on top of his losses and avoid dehydration. He picked up cups of water from the aid stations to avoid having to carry any fluid himself, and took a couple of Electrolyte Capsules. Although Nick’s relative sodium intake was fairly close to his losses based on the Sweat Test results, he still experienced some twinges of cramp towards the end of the race. This may mean his fluid replacement was less than his actual sweat losses even in the mild temperatures. It’s worth noting that muscle fatigue accumulated throughout the race may also have caused these twinges, as cramp is multifactorial.. It’s worth noting that muscle fatigue accumulated throughout the race may also have caused these twinges, as cramp is multifactorial.
Caffeine
Beyond the Three Levers of Performance (carb, sodium and fluid), caffeine is one of only a few substances that is proven to improve performance for most endurance athletes as it can help stave off mental and physical fatigue.
T - 0-4hrs: Had a final hit of caffeine
Nick consumed one caffeinated gel during the race, delivering a relatively small dose of caffeine, but since he had some coffee with his breakfast, it’s likely the stimulant was still in his system by the time the race began. To fully reap the ergogenic benefits of caffeine in future marathons, he could add a larger dose *during* to top-up, and fall more in line with the scientific recommendations. This would hopefully help Nick maintain his energy levels, and reduce the perception of effort later on.
How Nick hit his numbers
Here's everything that Nick ate and drank on the day...
Final thoughts
“I had a plan before the event and really tried to stick to it. If it wasn't for the GI discomfort, I think I would have been able to take more gels, but I am fairly happy with my performance overall.”
“Nick had a good race at the London Marathon, but suffered with some GI discomfort which negatively impacted his fueling strategy. Going forward he can use gut training to improve this area and allow for a higher carb intake. Additionally, fine-tuning his exact fluid losses with sweat rate testing may also assist the likelihood of cramp and avoid any other dehydration-related issues, possibly further positively impacting his GI comfort.”
PF&HNick's full stats
Data Confidence
We rate each of our case studies from 1-5 based on the level of accuracy, and our confidence in the data.
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.