IRONMAN 70.3® World Championships

Pre-race Fueling:

Chris (otherwise known as ‘Minty’) is not afraid to practice what he preaches as one of our Sports Scientists. Carb-loading is a strategy which maximises or ‘supercompensates’ muscle glycogen stores, and requires a dedicated high-carb intake of between 8-12g per kg of bodyweight. Minty pre-planned this the day before his race, tracking his intake closely and recording a whopping ~1,042g of carbs (which you can see a full menu of in the photos above). He primarily used PF Carb Only Drink Mix which also kept him hydrated whilst spectating the women’s race in the New Zealand sunshine. This converts to ~14.6g per kg of his bodyweight, which was deliberately higher than the guidelines as he spent much longer on his feet than normal the day before a race, thus burning more energy. On raceday, Minty said he’d never felt so punchy on the bike, and didn’t fade at all so it’s safe to say this science-backed strategy worked well for him.

Race Fueling:

Minty followed his Strategy Sticker plan almost to a T during the bike and run. He consumed a higher intake during the bike leg (~151g/h), which he felt was slightly too much by the 45km mark, so he backed off towards the end and focused on getting more fluids in. During the run his intake almost halved, but was enough to keep his energy levels high and avoid any GI discomfort.

Minty has a high sweat rate to match his above average sweat sodium concentration, so placed a high priority on fluid replacement during this race. The temperatures on race day were fairly warm (~25℃ / 77℉) and following a period of heat acclimation in the Precision Performance Lab, Minty knew he would be losing >2L (64oz) of sweat per hour for the majority of the race. By drinking >1L (32oz) of fluid per hour on the bike and run, he successfully replaced a decent proportion of his sweat losses. Coupling this with an appropriate amount of sodium would have encouraged some acute fluid retention and replaced his high sweat electrolyte losses. He drank a lot of water on the run, preferring the plain taste to anything else, so perhaps next time he may consider taking some Electrolyte Capsules to avoid over-diluting the relative sodium concentration of his fluids.

Minty frequents the office coffee machine on a daily basis, so it’s no surprise that he utilised the stimulant to enhance his performance on race day. He chose to abstain from caffeine for the 2 days prior to the event. The mechanism for his thinking was simple; caffeine blocks adenosine receptors, which reduces fatigue and improves alertness. Regular caffeine consumption can increase adenosine receptor density, meaning more caffeine is required to achieve the same blocking effect. Abstinence has previously been theorised to ‘reset’ the receptors, allowing for greater performance benefit when reintroduced during exercise. There have been plenty of studies showing little-to-no difference in performance between those who undertook small periods of abstinence compared to those who didn’t, but given the individual responses to caffeine, Minty felt a benefit when reintroducing the stimulant during the race.