PTO US Open
Sam'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.
Sam was able to frontload his carb intake on the bike to reach an impressive ~120g/h with “no stomach discomfort at all”. Sam placed a big focus on training his gut to tolerate more carb during the 2023 season and it’s clearly paid off. His average carb intake throughout the whole race in Milwaukee was ~81g/h, which is a significant step up from the average of ~58g/h he hit during his previous five middle distance races.
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 Sam’s losses are on the low side, getting his hydration strategy right is still crucial when it’s hot and/or humid as his higher sweat rate in these conditions can result in significant net losses over the duration of a race.Learn more
In the hot Milwaukee conditions, Sam averaged a slightly higher fluid intake than we’ve seen from him previously, ~669ml per hour. By carrying one bottle with two PH 1000 tablets and a second bottle with one PH 1500 tablet on the bike, Sam proactively took on a relative sodium concentration of 928mg/L, which is slightly above his sweat sodium losses of 655mg/L. Considering the fact that he experienced some slight hamstring twinges on the run, he may have benefitted from using the special needs aid stations to pick up more electrolytes to maintain the concentration he was consuming at the most humid point of the race.
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.
Sam’s caffeine intake was a little short of the general recommendations for performance. Considering caffeine takes ~45 minutes to peak in the bloodstream and has a half-life of ~4-5 hours, he may want to consider taking on some caffeine in the final 30 minutes before future races to increase his perceived energy levels before topping up with a PF 30 Caffeine Gel on the bike leg to set him up for a strong run.
How Sam hit his numbers
Here's everything that Sam ate and drank on the day...
Sam's weapons of choice
Sam's full stats
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).