
Justin Metzler
IRONMAN 70.3® Augusta
Justin's headline numbers
Justin'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.
Justin has hit an average carbohydrate intake of more than 100 grams per hour this season at Oregon 70.3 and Eagleman 70.3, and it was superb to see him do the same again here in Augusta. This is undoubtedly supported by his consistent and successful gut training to tolerate this higher quantity of carb with no GI discomfort. For someone who has previously suffered from significant issues, his additional practice in training has helped him reap the benefits of proper fueling with no distress. After ‘front-loading’ a large proportion of his carb intake for the bike leg, Justin took a further ~85g of carb during the half marathon, giving him an overall average of ~70g/h on the run.
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.
Whilst Justin’s losses are on the moderate 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 moreJustin has suffered from debilitating leg cramps in previous races, and has worked hard to over come these by working on his hydration strategy. Primarily he’s reduced his total fluid intake, alongside extensive gut training. The relative sodium concentration of the drinks he consumed on the bike was higher than we would recommend at 2073mg/L. Still, Justin’s intake tapered off significantly on the run to just ~393mg/L, which brought his average across the entire race to a more sensible ~1,899mg/L. This is a similar action of ‘frontloading’, which we’ve seen Justin execute previously and is something we’ve recommended given his moderate-to-high sweat sodium concentration as measured by our Sweat Test.
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.
Justin has often exceeded the recommended range for caffeine intake during endurance events. However, this strategy works well for him and allows him to reap the performance benefits from the stimulant throughout races with no associated issues.
How Justin hit his numbers
Here's everything that Justin ate and drank on the day...
Justin's weapons of choice
Final thoughts
Justin'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).