Samantha Skold
IRONMAN® World Championships
Samantha's headline numbers
Samantha'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.
Sam crushed her fueling at this championship race, showing a ~23g per hour increase from last year’s carb intake in Kona and boasting a perfect 10 out of 10 for GI comfort. After carb loading, enjoying part of a baguette on race morning and topping up with a pre-swim gel, she got started on her fueling soon after clipping in on the bike leg. She used a combination of PF Carb & Electrolyte Drink Mix plus PF Gels to hit an average of ~107g/h on the bike. This is extra impressive considering the tricky nature of the bike course in Nice. Her consistent fueling continued on the run with PF 90 Gels and paid off big time with the fastest amateur run split on the day (and 7th fastest including the pros)!
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 Samantha’s losses are on the moderate side, getting her hydration strategy right is still crucial when it’s hot and/or humid as her higher sweat rate in these conditions can result in significant net losses over the duration of a race.
Learn moreConditions on race day weren’t extreme, so Sam managed to stay on top of her fluid intake, closely matching her sweat rate, averaging nearly the exact same fluid intake as in Kona 2023. Frontloading more of her hydration on the bike vs. the run (~1.1L/h vs. ~601ml/h) made sure she wasn’t dehydrated by the time she hit the marathon, and although she would’ve liked to take in more fluid, she was smart to carry a concentrated soft flask of PH 1500 (Drink Mix) to use the water retaining properties of sodium to her advantage. Sam did note a cramp in her upper abdomen on the last part of the bike but put this down to posturing on the bike while descending, as it thankfully went away as soon as she started running. She also had tingling in her hands during the last two miles of the marathon, but considering her sodium concentration was significantly higher on the run (~1,947mg/L), it may have been due to a lower fluid intake than planned, and some cumulative fatigue.
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.
Sam consumed just over the top end of the recommended range (3-6mg per kg body weight) for caffeine to reap its performance benefits. Considering the duration of the race and her tolerance to the stimulant, the slightly higher dose worked well for her and helped mask fatigue throughout.
How Samantha hit her numbers
Here's everything that Samantha ate and drank on the day...
Samantha's weapons of choice
Final thoughts
PF&HSamantha's full stats
Data Confidence?
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.