Julie Dunkle
IRONMAN® World Championships
Julie's headline numbers
Julie's strategy
Fueling
Carbohydrate is the main fuel you burn when racing. Failing to fuel properly is a leading cause of underperformance in longer races.
Julie had a strong nutrition plan, starting with a PF 30 Gel 15 minutes before the race to top up her energy levels and spare glycogen stores for later. Though she intended to consume ~60g/h of carb throughout the race, she fell just shy of this target, and averaged substantially less than the recommendations (+90g/hr) for a race of this duration and intensity. This unplanned lower intake was largely due to the mild GI distress she experienced toward the end of the bike, causing her to reduce her carb intake on the run to avoid further exacerbating her stomach issues. While this kept any further GI distress at bay, it would be beneficial for Julie to do some structured gut training in her longer and key training sessions in the build up to her next race to ensure GI comfort with higher carb intake to maintain her 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.
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 Julie’s losses are High (1,167mg/L), nailing her hydration strategy becomes especially crucial when it’s hot and/or humid.
Learn moreJulie went into the race with optimal hydration thanks to preloading, and also had a well-thought out strategy for her fluid and electrolytes during the race. After performing some sweat rate testing, Julie knows she is a heavy sweater and can lose up to 2L/h during some sessions. As a result, she made sure to drink frequently throughout the race and consumed a total of ~10L of fluid. As her fluid intake was below the recommendations for these hotter conditions, she may want to increase her fluid intake to stave off any negative symtpoms of dehydration, which may have contributed to her GI discomfort later in the race. Julie used a combination of Electrolyte Capsules, Electrolyte Tablets, and PF Carb & Electrolyte Drink Mix to match her personal sweat sodium losses, determined by a Sweat Test. By consistently taking on adequate sodium throughout the race, she avoided muscle cramps and any other negative side effects further suggesting she was hydrating appropriately.
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.
Julie started the day with a cup of coffee at breakfast but didn't take much caffeine during the race other than a very small amount via a few cups of energy drink during the run. Since her total intake was significantly below the scientific recommendations of 3-6 mg/kg, she could try using PF 30 Caffeine Gels during training so see if she tolerates the stimulant well and could reap the ergogenic benefits caffeine has to offer in a race.
How Julie hit her numbers
Here's everything that Julie ate and drank on the day...
Julie's weapons of choice
Final thoughts
PF&HJulie's full stats
Data Confidence?
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).