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James Phillips

Paris Marathon

2nd April, 2023
France
Paris
strava
Running, Marathon - 42.2km
7°C
, Mild
2hrs 37mins
more race details

James' headline numbers

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?
?
~83
g
Carb per hour
Recommended 75g/h
~237
ml
Fluid per hour
Recommended 100-500ml/h
~2,419
mg
Sodium per litre
Recommended 1600-2000mg/L
~2.8
mg
Caffeine per kg
Recommended 3-6mg/kg

James' strategy

Fueling

Carbohydrate is the main fuel you burn when racing. Failing to fuel properly is a leading cause of underperformance in longer races.

Carb-loaded
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T - 1-4hrs: Ate a carb rich meal (Low in fat & fibre)
pre-fueled
?
T - 15mins: Took in a final dose of carb
Carb per hour
Recommended 75g/h
~83
g
James' Energy Rating
10
/10
"I've practiced a lot with carbohydrates and finding what works for me so found it really easy to take on what I needed and stick to my fueling plan during the race to keep my energy levels up. "
Our thoughts

James (JP) is well versed in the realms of carbohydrate loading, and even co-wrote our blog post on how to carb load for your next race. So, it was no surprise to see plenty of high-carb foods in his pre-race intake, finishing with some slices of toast and jam for breakfast on race morning. After tracking his glucose response with a continuous glucose monitor (CGM) in training, James was able to assess his optimal time frame for carbohydrate ingestion pre-race, and executed a perfect plan by taking a pack of PF 30 Chews within the last 20 minutes before the start. JP also compared his glucose response between three sources of carbohydrates – PF 30 Chews, PF 30 Gels and PF 60 Drink Mix. he decided to use PF 30 Gels as his primary fuel source during the race as he found these suited him best and were easiest to consume whilst running at ~3:44 per kilometre (6 minute miles)

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.

James1850mg/L
James 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.

Given James’s losses are Very High (1,850mg/L), nailing his hydration strategy remains important, even when it’s Mild.

Learn more
Pre-loaded electrolytes
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T - 60mins: Drank ~500ml of strong electrolyte drink
Fluid per hour
Recommended 100-500ml/h
~237
ml
Sodium per litre
Recommended 1600-2000mg/L
~2,419
mg
James' Hydration Rating
9
/10
"If I did the race again, I would carry some Electrolyte Capsules and pick up more water at the aid station"
Our thoughts

Unfortunately, JP forgot his tube of PH 1500s when leaving the UK and heading to France for this race (something we won’t let him live down anytime soon). Thankfully, he knew the relative sodium concentration involved in preloading was one of the most important factors to consider, and subsequently used 1.5 x PH 1000 Tablets in 500ml to achieve the desired concentration of 750mg of sodium in 500ml of water. During the race he carried a Soft Flask filled with three PH 1000 Tablets, and planned to drink some plain water from the aid stations to effectively dilute this concentration to match his losses. JP didn’t pick up as much water as he’d planned, partly because temperatures were lower than expected, decreasing his perception of thirst and overall sweat losses. As a result, he consumed fluid contraining an extremely high relative sodium concentration in his fluid during the race.

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.

Pre-caffeinated
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T - 0-4hrs: Had a final hit of caffeine
Caffeine per kg
Recommended 3-6mg/kg
~2.8
mg
Our thoughts

Despite consuming two PF 30 Caffeine Gels during the race, JP's intake fell slightly below the scientific recommendations for caffeine. For his next race, he would benefit from consuming a PF 30 Caffeine Gel in the last 30 minutes before the race to give him an additional energy boost and lower his perception of effort during the race.

How James hit his numbers

Here's everything that James ate and drank on the day...

James' weapons of choice

Final thoughts

James' Satisfaction Rating
9
/10
I raced with a "limiter" on so I didn't blow up, but as my last 5k was my fastest, I feel this has generated an itch I want to scratch at some point!
James
Overall, JP executed a solid fuel and hydration plan that he’d worked to fine tune during training. Paired with a sensible pacing strategy, he was able to stay on target and finish strong to the end. For his next race, he can make small adjustments to his plan to ensure his caffeine intake and relative sodium concentration are even further dialled in.
PF&H

James' full stats

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?
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Overall
216g total carb
83g per hour
620ml total fluid
237ml per hour
1,500mg total sodium
573mg per hour
2,419mg
Sodium per litre
200mg total caffeine
2.8mg per kg

Data Confidence
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We rate each of our case studies from 1-5 based on the level of accuracy, and our confidence in the data.
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2
3
4
5

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).

James' recent case studies

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