Jack Davis' scorecard
Paris Marathon
Sunday 2nd April, 2023
Within recommended ranges
Just outside recommended ranges
Significantly outside recommended ranges
70g
Carb per hour
414mg
Sodium per hour
331ml
Fluid per hour
1,250mg/L
Relative sodium concentration
2.53mg/kg
Caffeine per bodyweight
How Jack hit those numbers
How Jack's hydration and fueling went...
- Jack is the newest member of the PF&H team and Paris was his first standalone marathon having run the distance twice but only at the end of an IRONMAN triathlon. You can actually see how Jack’s strategy compares to his case study at his most recent IRONMAN in Utah
- He crushed his pre-race fuel and hydration plan and finished just outside of his target time of three hours, having been on-track until some painful muscle fatigue in the latter kilometres slowed him down
Hydration
- Jack may be new to the team, but understood the importance of preloading his sodium levels to ensure he started optimally hydrated. To do this, he emptied a PH 1500 packet into 500ml of water, and finished it around an hour before the race started
- During the race itself, Jack regularly picked up plain water from the aid stations, totalling ~1L (32oz) across the race
- To ensure he replaced a good proportion of his electrolyte losses, Jack carried some Electrolyte Capsules with him, taking five throughout the race. This meant the relative sodium concentration of his fluid intake was ~1,250mg per litre (mg/32oz)
- As Jack’s sweat sodium concentration, measured by our Sweat Test, is 983mg/L (mg/32oz), he did a good job of electrolyte replacement, but could perhaps have increased his fluid intake a little to reduce the saltiness to be more in line with his sweat losses
Fueling
Quick Carb Calculator Recommendation
30g
carb 30 mins before
75-90g
carb per hour during
- Jack began the race fully stocked on glycogen after a strong carb-load for the 48 hours prior, finishing with a small amount of honey on a freshly baked French baguette
- He then initiated some glycogen sparing by taking his PF 30 Gel around 20 minutes before the gun went off, which will have helped him maintain good energy levels later in the race
- The timing of this pre-race gel is something Jack has helped to dial in by using a continuous glucose monitor from Supersapiens, and found optimal increases in blood glucose occurred between 15-25 minutes after intake, so chose to utilise this for the race
- His fueling strategy during the race was simple, taking ~30 grams of carb every 25-30 minutes. Jack sipped on a PF 90 in the first half, then consumed two PF 30 Caffeine Gels and a non-caffeinated PF 30 Gel in the back half
- Overall, his average carb intake was ~70g per hour, which is slightly below the amount we’d recommend for an event of this duration and intensity, which is between 75-90g per hour
- Jack managed to keep his perception of energy high, likely due to a combination of his regular carb and caffeine intake. His caffeine intake was again, slightly below the 3-6mg/kg recommended in the literature to achieve maximal benefit, but at 2.5mg/kg, he would still have seen a reduction in perceived effort
Conclusions
- Overall, Jack’s first ever standalone marathon went very much to plan, with only his total time slightly falling below what he’d hoped
- From a fueling and hydration perspective, Jack took great confidence in how well he executed his plan, and put the slight fade in pace towards the end down to muscle fatigue
Key info
Jack Davis
Male
79kg
Sweat sodium concentration
983mg/L
Sweat sodium classification
Moderate
* determined by a PH Advanced Sweat Test
Event information
Sport
Running
Discipline
Marathon
Event
Paris Marathon
Location
Paris, France
Date
2nd April, 2023
Website
Total Distance
42.2km / 26.2mi
Total Elevation
269m / 883ft
Race conditions
Weather Conditions
Mild
Precipitation
Rain
Min Temp
6°C / 43°F
Max Temp
8°C / 46°F
Avg Temp
7°C / 45°F
Humidity
85%
Athlete feedback
Race Satisfaction
9/10
Hydration rating
10/10
Energy levels
9/10
Toilet stops
No
GI comfort
10/10
Cramping
Twinges but not full-on cramps
Jack's Thoughts
My fuel and hydration plan felt spot on, muscle fatigue was my main limitation towards the end but overall I'm happy
Jack's full stats
Carbohydrate (g) | Sodium (mg) | Fluid (ml) | Caffeine (mg) | Relative sodium concentration (mg/L) | |
---|---|---|---|---|---|
Overall | |||||
Total intake | 210 | 1,250 | 1,000 | 200 | 1,250 |
Per hour | 70 | 414 | 331 | 66 |
Data Confidence
1
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).