IM 70.3 World Championships
Claire's headline numbers
Carbohydrate is the main fuel you burn when racing. Failing to fuel properly is a leading cause of underperformance in longer races.
Despite having a mild stomach bug leading up to the race, Claire felt strong on the day and was able to execute a decent fuel plan despite a couple of adversities. The straw on her aero bottle became clogged so she couldn’t get half her planned carb and water from this. Claire’s other bottles containing PF Carb & Electrolyte Drink Mix helped her hit an appropriate carb intake in spite of this, and she powered through some minor dips in energy levels on the run with no stomach discomfort - a big personal success!
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.
Whilst Claire’s losses are on the moderate side, getting her hydration strategy right is still important if she wants to perform at her best.Learn more
Claire slightly overdid her sodium replacement during this race, averaging a concentration ~65% higher that which she loses in her sweat. Although she didn’t experience any negative side effects from this, we’d recommend she reduces the saltiness to fall more in line with her sweat losses. To do this, Claire could reduce the amount of sodium she takes by drinking some Carb & Electrolyte Drink Mix without the additional PH 1000 Tablets. Alternatively, in warmer conditions, where she’ll likely have a higher sweat rate, she may want to drink some plain water to help dilute the overall concentration.
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.
Claire’s caffeine intake was slightly over the scientifically recommended amount, but as someone with a high tolerance to caffeine, this was likely an appropriate amount for Claire. However, it’s worth bearing in mind that going above and beyond the recommended guidelines won’t necessarily yield any further ergogenic benefits, so sticking within them is usually optimal.
How Claire hit her numbers
Here's everything that Claire ate and drank on the day...
Claire's weapons of choice
Claire's full stats
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.