• Amy Cutherbertson is one of ten female athletes that the Precision Fuel & Hydration Team have been working with in collaboration with the Voxwomen Performance Project. Upon joining the project, as someone who could ‘ride well, ran a bit, but couldn’t swim’, Amy’s personal goal was to complete a middle distance triathlon at the end of the six months
• With the help of the Sports Science Team and the team at Supersapiens, Amy, learned how best to fuel and hydrate to optimise her performance. This helped her to achieve her goal, in a time of 6 hours and 56 minutes
• On race day, Amy did a great job at managing her fuel and hydration needs despite the very hot weather conditions (highs of ~32℃/90℉), following her plan and hitting her targets on the bike and having the confidence to listen to her body on the run

Hydration

• Having checked the forecast ahead of time, Amy knew she would be racing in hot conditions >30℃/86℉ and would therefore be incurring significant sweat losses. With that in mind, to ensure she started well-hydrated, Amy drank 500ml/16oz of PH 1500 alongside her breakfast; a strategy which encourages the body to retain a greater proportion of the fluid drunk as well as starting with acutely more sodium on board
• During the race, all three of Amy’s 750ml/24oz bike bottles were filled with PH 500 (Drink Mix), with two of them also containing PF 30 Drink Mix. Amy depleted all three bottles on the ride, drinking an average of ~631ml/h (21oz/h), and then chose to run out of transition with another 500ml/16oz flask of PH 500
• At this point, temperatures were high, and what Amy was craving the most was just plain water. With that being the case, Amy drank half of her PH 500 flask before discarding it and drinking “as much water as I could get my hands on”
• Amy estimated that she drank ~18 cups of plain water during the run (~6 cups per lap of the three lap course) equating to ~1.8L/60oz of water (~100ml per cup). In total, we estimate that Amy drank ~2.05L/64oz on the run, averaging ~872ml/h (29oz/h). This is a relatively high average fluid intake but it reflects the high temperatures Amy was racing in
• The craving for plain water Amy experienced on the run is a reflection of the hot temperatures at that stage in the race, as well as, being a likely consequence of drinking only sodium-rich drinks during the bike leg. The relative sodium concentration of Amy’s drinks on the bike averaged ~951mg/L, a moderate-to-high concentration. Amy hasn’t had an Advanced Sweat Test so we don’t know her sweat sodium concentration (how many milligrams of sodium she loses per litre of sweat), however she perceives her sweat sodium losses to be low, as well as her sweat rate. Therefore, her net sodium losses may not have been too high
• Amy’s pre-mixed bottles were great choices on the bike but balancing these with some plain water to dilute the relative sodium concentration would be advised for future, warmer races of a similar duration
• Amy rated the appropriateness of her hydration strategy an 8 (out of 10), but not for lack of a suitable plan, instead, due to a lack of available water on the run, saying “two aid stations per 7km lap wasn’t enough in plus 30℃”

Fueling

Conclusions

• Amy did a great job in her first ever middle distance triathlon in very challenging conditions; following her plan on the bike and adapting well on the run!
• One adjustment to Amy’s strategy would be to drink some plain water on the bike alongside her pre-mixed bottles. This change will slightly reduce the relative sodium concentration of Amy’s consumption, which may have a positive influence on her strong craving for water in the latter stages of the race