CJ Albertson
Chicago Marathon
Chicago13th, MPROCJ's headline numbers
CJ's strategy
Fueling
T - 1-4hrs: Ate a carb rich meal (Low in fat & fibre)
T - 15mins: Took in a final dose of carb
"My energy felt good. Having so many carbs overnight I think helped. I didn’t force calories late in the race, so I had no stomach issues."
CJ’s biggest change from the Boston Marathon was his overnight fueling. He always wakes several times before a marathon, so he split 22g of sodium bicarbonate across those wake-ups between 9 pm and 4 am, alongside four PF 30 Gels and a 40g carb drink mix. With three-quarters of an energy bar and a PF 30 Caffeine Gel on top in the morning, he started the race with over 3g of carbohydrate per kilogram of body weight on board. During the race he averaged ~113g/h largely from a PF 30 Gel every 5km plus some dilute PH 1000 Sachets, slightly up on ~108g/h in Boston and well into the >90g/h high carb intake territory. Late on, he only consumed part of his gels and even rinsed and spat at 40km, since there was too little time left to absorb it and feel a benefit during the race, and a carbohydrate mouth rinse can still ease perceived effort. No GI issues with a pre-race ~0.34g/kg dose of bicarb stands out, as stomach upset is the main reason athletes avoid it. Splitting the dose and pairing it with carbs both help, and he plans to keep doing that in training. With carb intake this high, his ~10-15g of ketone esters are unlikely to add anything and could be trimmed.
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.
CJ983mg/L
CJ 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 CJ's losses are on the moderate 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 felt well hydrated and had no thirst during or after the race."
Similar to other professionals in our Athlete Case Study Database CJ drinks low volumes across the marathon distance, taking on a similar amount overall to Boston; ~424ml/h here vs ~442ml/h there. Pouring water over himself at every opportunity cools him without the time or GI cost of drinking more. So, even though the total volume may seem low, he likely finished around 2-3% down on body mass, which is within the range of dehydration most athletes tolerate well, and having no thirst during or after backs that up.
His relative sodium concentration of ~222mg/L looks low against his 983mg/L sweat sodium concentration, but the 22g of bicarb provided ~5.9g of sodium overnight, likely around double his race sweat losses. The bicarb would have acted as his sodium preload, so reducing the sodium concentration of his drinks down, but not removing sodium entirely, was the right call to avoid overdoing the sodium.
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
CJ’s overall pre-race caffeine intake totalled ~300mg (~4.6mg/kg) all on race morning. This included 100mg within 30 minutes of the start in the form of a PF 30 Caffeine Gel and two 100mg pills which he took earlier at 80 and 50 minutes before the start, putting CJ in the middle of the 3-6mg/kg range
How CJ hit his numbers
Here's everything that CJ ate and drank on the day...
Final thoughts
“Everything went to plan. Eating and drinking well during marathons is really natural for me now, so it’s one less thing requiring mental energy. I felt energised the whole time.”
“A new PB by almost a minute (previously 2:08:17, Chicago 2024) and 13th in a deep field was a great result for CJ in Chicago. Similarly to Boston, everything went to plan. The overnight bicarb and carb routine was the standout, giving him a big carb top-up, covering his sodium needs before the start and causing no GI issues.”
PF&HCJ'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 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).