Nutrition, Podcast, Racing

Nutrition and hydration data from Kona and 70.3 Worlds with Andy Blow | EP#365

 November 21, 2022

By  Bernardo Gonçalves


Andy Blow - That Triathlon Show

Andy Blow of Precision Fuel & Hydration joins us to discuss the exact numbers of carbohydrate, fluid and sodium intake of Fenella Langridge, Sarah Crowley and Leon Chevalier (all top-10 in Kona) as well as Emma Pallant-Browne (third in the Ironman 70.3 World Championships in St George). 

In this episode you'll learn about:

  • Carbohydrate, fluid, and sodium intake of Fenella Langridge, Sarah Crowley and Leon Chevalier in Kona
  • How Kona differs from most other Ironman races due to the extreme environmental conditions
  • Carbohydrate, fluid, and sodium intake of Emma Pallant-Browne in 70.3 Worlds
  • How to change your nutrition and hydration plan for cold conditions like this year's race in St George
  • The process Fenella, Sarah, Leon and Emma go through when they come up with their race hydration and nutrition strategies

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Athletes that Andy got data from

02:51 -

  • We could compile data from 11 athletes racing in Kona this year.
  • Kona is a unique race from a hydration and nutrition standpoint, so we focused on getting as much data as possible.
  • We got data from pro-triathletes who are ambassadors for the brand: Leon Chevalier, Fenella Langridge, and Sarah Crowley, who were in the top 10.
  • Sarah felt that her race could have been better because of the penalty she got.
  • However, getting information from three top 10 athletes was fantastic.
  • We also got data from other age group winners and top age group athletes who did well in the race.
  • We got a lot of data on how those individuals executed fuel and hydration strategies, and that would allow us to compare this data with other Ironman races. In this way, we can compare how athletes can adapt their strategies for Kona.

How fuelling and hydration strategies in Kona compare to other Ironman races

04:31 -

  • People hydrate a lot more in Kona.
  • Even watching as a spectator, you understand how ridiculously high humidity is. (Your shirt is sticking to you all day long)
  • Therefore, fluid loss is massive.
  • At the group level, we saw some of the highest fluid intakes we had ever seen in an Ironman.
  • The highest was 1.5 L/h throughout the event.
  • Leon took close to 1.4 L/h, which showed us what high fluid intakes are in this competition.
  • While, for example, Leon's fluid intake is high, it is not higher than in previous data we have.
  • One interesting thing is that I do not think he peed on the bike.
  • You would expect that if you were putting a significant fluid overload, you would see people needing to pee or feeling uncomfortable.
  • Leon rated his GI comfort as 8/10. He had some issues on the bike because he was trying to hit high fluid intake there.
  • He pushed those limits, but he did not go over them.
  • We know Leon is a heavy, salty sweater, so high sodium and fluid intake is essential for him in the heat.
  • We plan for him to get his bottles with fluid and carbs to get the totals in and to supplement with as low additional water as possible.
  • I cannot confirm data from Sam Laidlow, but he mentioned in interviews taking 2 L/h on the bike, which sounds high. However, we had athletes taking over 1.5 L/h on the bike, so it suggests that pushing fluid intake high correlates with performance on the day.

How Leon deals with maintaining high sodium intake during the race

10:16 -

  • On his bike, he tends to carry two one-litre bottles that contain energy gels, some water and PH1500 electrolytes. (extremely concentrated mixtures)
  • He will have a 500 mL bottle, so we have 2.5 L in total capacity.
  • During the race, he is primarily picking up plain water.
  • According to our stats, he picked up 4.7 L of plain water during the race. 
  • For Pro athletes who race close to 4h, it becomes easy to do that because they do not have to carry calories for 5-7h.
  • Moreover, this strategy allows athletes to know exactly how much they consume.
  • Top athletes can predict their performance within a few minutes if things go as scheduled.
  • If they have to hit 100 g/h, you must carry 400g/h.
  • We encourage athletes to take more than they need in case they need more.
  • If you dump 90 grams of gels into a bottle, you will not get every gram out of that bottle.
  • We typically say that if you want to hit 400, take 430-440 grams of carbs.
  • Moreover, this takes the pressure off taking special needs bags or getting items from aid stations.

Fueling and hydration intakes from the top athletes

13:02 -

  • Leon's fluid intake was about 1.38 L/h.
  • Fenella's was 1.1 L/h. Fenella is only 55-56 kg, compared to Leon's 78 kg, so it is a high fluid intake for Fenella.
  • We know that Fenella has a high sweat rate.
  • Sarah has a similar weight to Fenella but only had 583 mL/h, half of what Fenella takes.
  • Sarah seems to perform well with less fluid compared with other athletes.
  • Calculating sweat rates is specific to the intensities and the environment you are testing on, so unless you compare athletes at the same conditions and intensities, it will be challenging to make a comparison.
  •  Nevertheless, Sarah has a significantly lower sweat rate subjectively than the other two athletes.
  • Fenella and Leon have adapted to racing in hot conditions, but Sarah has a track record of racing in hot conditions.
  • If Sarah can do this on 600 mL/h, is taking 1.3 L/h excessive?
  • I am confident Leon would be too dehydrated at 600 mL/h because he needs more fluid than that.
  • However, we do not know how close he was to the upper limit compared to the lower limit, and it is a question we will refine with more experience.

Sodium intake for these three athletes

16:00 -

  • Leon took 922 mg/h of sodium.
  • Fenella took 1300 mg/h.
  • Sarah took 230 mg/h.
  • We expect Sarah to take less sodium because her sweat sodium concentration is lower. Moreover, as she is taking less fluid, we do not need to be aggressive with the sodium intake because a low amount of fluid intake only requires a low amount of sodium intake.
  • As you scale your fluid intake, you need to increase your sodium intake to meet the percentages of your total losses.
  • Both Fenella and Leon are significantly saltier, so they take more sodium as a result.
  • If we consider relative terms, Leon takes only 700 mg/L because he took a lot of fluid. Fenella was at 1100mg/L, and Sarah was at 400 mg/L.

Athlete's sweat sodium concentrations

18:07 -

  • Leon is typically around 1300 mg/L.
  • Fenella's is similar at around 1300 mg/L
  • Sarah's is much lower at 500 mg/L.
  • Therefore, the strategy fits their relative losses.
  • If we redesigned the hydration strategy, we would consider increasing Leon's intake more because his replacement was 50 % of his losses.
  • He had a strong performance without any decrements, so we could argue that he got it right.
  • I feel he was slightly on the lower side rather than pushing the upper end.
  • Fenella did not drink as much as she sweated, but she was almost 1:1 in relative terms.
  • However, all athletes rated their hydration high.
  • Leon rated his hydration 10/10.
  • Fenella rated hers 8/10 because she was apprehensive about not having raced in those conditions before.
  • Sarah said she nailed her hydration plan perfectly, 10/10.
  • However, trying to isolate a variable and attribute success to it is impossible because many complex things are happening in the body. 
  • You can say that these athletes achieved something close to their best performance on the day.
  • If you zoom out at their hydration strategy, we could say they were in the zone that allowed them to compete optimally in those conditions.
  • Their hydration strategy did not cause a catastrophic failure or compromise their performance.

Carbohydrate intake

22:56 -

  • Pros consume 22 % more carbs than the age groupers.
  • The average carb intake, even in the age groupers, was 85 g/h, which is typically higher than what we see in most Ironman races.
  • However, it is the World Championships and the average time for our group was 9h30. So, we expect athletes to be well-conditioned.
  • We understand that a high carb intake supports a high output level, and these athletes are at the highest end.
  • The lower carb intake was 66 g/h, and the highest was 120 g/h.
  • Both of these values are between what we consider optimal for this race.
  • Leon was 105 g/h, Fenella 96 g/h and Sarah 70 g/h.
  • Leon has been working to increase his intake.
  • Fenella was someone that significantly increased carb intake.
  • Sarah did a solid job, but like her fluid intake, Sarah appears to be an athlete that can race towards the lower end of the recommendation.
  • It could debate if she could take more from her if she ingested more carbs, but that might be questionable.
  • Sarah is an experienced athlete that knows her body well.

Plan vs execution

26:36 -

  • These three athletes executed the plan.
  • We do not like to make target fluid intake values because they vary greatly.
  • We told athletes to get that required amount of electrolytes and to supplement with water as they feel it.
  • There is no water shortage available on the course in many of these races, so they took advantage of that.
  • In the future, we will push Leon's sodium intake a bit, knowing that he will likely consume more plain water.
  • All athletes that finish the race strong keep their carb intake up deep into the marathon. (which is hard to do)
  • There was a lot of action at the end of the race, as Leon dropped to 9th at some point and came to finish and almost caught Kienle.
  • It is tempting to let your intake taper off at the end of the race, especially if your race is not going well. However, you will likely have a strong finish if you keep consuming.

Carb intake distribution

29:06 -

  • Leon took more carbs on the bike (140 g/h). He took 80 g/h on the run.
  • It is a typical habit for him, and we encourage him to do it to set up a good run.

Process of developing a nutrition strategy

30:26 -

  • If they work with us, we try to act like advisors and avoid dictating.
  • Most of these athletes are already doing most things right, so we advise looking at what they are doing and modifying it to improve it. (unless their strategy is not good)
  • First, we understand the goal number they want to hit.
  • If Leon wants to hit 140 g/h on the bike and 80 g/h on the run, we offer a product range, and they select which ones they will take for each part of the race.
  • For example, some athletes do not want energy gels and prefer energy drinks or chews.
  • Therefore, we would be silly to give those athletes the same plan we give Leon, where he takes gels on bike bottles.
  • We will also analyse whether we need to change those targets (going up or down)
  • We also want athletes to present us with a plan, and we will help them figure out the best way to proceed. (foods at aid stations if they plan to pick nutrition)
  • For example, Leon would send us a spreadsheet, and we would check the math and numbers to ensure everything added up.
  • We will take that and compare it to previous races in similar conditions.
  • Then, we would make advisory comments on that.
  • We believe this being a partnership instead of us telling the athlete what to do will lead them to learn the best practices for each event.
  • It all boils down to understanding how the numbers vary in different distances and conditions and moving them up and down.
  • For example, Leon presented us with a plan based on what he did on Ironman Mallorca (where he was successful). (same carb intake and more fluid and sodium intake)
  • Athletes will repeat the most comfortable routines and then repeat with minor tweaks.
  • Leon increased his sodium intake slightly, expecting to pick up more water.
  • We are talking with a PhD student whose researching sodium and fluid intake in ultra-endurance, and we want to figure out the following:
  • Is there a correlation between the sodium/sweat athlete model from a neutral environment (20ºC on the trainer) and in a hotter environment (30º and high humidity)? Can we estimate increases in sweat loss and advice on fluid intake?
  • We try to gather data from previous races on an athlete because there is a reason to do what they have done in the past, so we need to unpick what those reasons are and see if those strategies were successful or not.
  • Improving a good to a great strategy is better than starting from a clean "board".

How Fenella and Leon will plan their nutrition for Kona 2023

37:20 -

  • We will build the plan from what we did this year unless we learn something this year.
  • We understand that carbohydrate tolerance changes over time.
  • We would not persist with 140 g/h of carbs if he did it in other races and found it intolerable.
  • However, athletes have a starting point to work for next year.


38:21 -

  • Having races or training periods in similar conditions to Kona is essential to figure out what you need to do with sodium and fluid replacement.
  • We have worked with athletes with exceptionally high sweat rates and sodium losses who consistently performed poorly in Kona because of the mismatch between the intake and the losses.
  • The most important is figuring out if you are one athlete who might benefit significantly from paying extra care to this topic.

70.3 World Champions - Overview of the strategies implemented

39:57 -

  • In general, athletes were not prepared to race in those conditions.
  • For example, athletes struggled to put clothes on, and people wore warm clothes below their expensive suits.
  • It shows how badly the sport is at dealing with those conditions.
  • Athletes that had their calorie sources coming from a liquid intake struggled because you do not need to drink much in those conditions.
  • Some athletes reported not sweating during the race, so you cannot force fluid in during the race. If your calories come from fluid, you will perform worse.
  • Decoupling your calorie intake from your fluid intake is essential in hot conditions because you might overload your gut with all the fluid you take. It is the exact opposite in cold conditions because you do not drink enough to meet your caloric needs if you are not eating.
  • In cold conditions, it is also more demanding to eat when you have cold fingers and wearing gloves.

Intakes from pro athletes

42:53 -

  • Emma raced for 4h10 and finished 3rd. She took 28g/h of carbs, 288 mL/h and 740 mg/L of sodium.
  • You do not need much sodium or fluid intake in those cold conditions.
  • However, 28 g/h of carbs is low.
  • We did not expect to be that cold in the days leading to the race.
  • She planned to drink more liquids on the bike than she did.
  • She barely touched her high-caloric drink on the bike.
  • She managed to take a gel on the bike, but with the gloves, shivering and descents, she found it difficult to get in the nutrition.
  • Instead, she focused on riding as hard as she could and taking the risk that she would sustain to run a good half-marathon.
  • Once she finished the bike, she grabbed cups of Gatorade and tried to make up for the caloric deficit in the early parts of the run.
  • Most of what she took in came at that race period.
  • However, you would never advise an athlete to take 28-30 g/h of carbs for four hours of racing in any event.
  • She could sustain her performance until the end, which was intriguing because of the importance of having a high level of fitness and motivation.
  • Emma did an excellent job of carb-loading before the event and showed that you could get a good result without optimally getting the nutrition.
  • I have yet to see Emma's bike power data, but that might have set her up to run quicker.
  • We also saw that the temperature increased on the run and Emma is typically an athlete that struggles with the heat.
  • Nevertheless, the conditions on the run were probably ideal for her.
  • Another point is that Emma is on another level concerning motivation.
  • So, this result meant much to her and sometimes you can dig deep and produce a phenomenal result even if things are not optimal around you.
  • People might say that this is an example that you do not need to take much energy, but it is ridiculous because nutrition and hydration are pillars of a strong performance. However, this pillar puts it into perspective with fitness, motivation, and pre-race preparation.

Adapting Emma's nutrition strategy for the conditions

50:39 -

  • We would advise consuming more gels and finding ways of making them more accessible with gloves and cold hands to have solid carbs.
  • Maybe, she could have used the 90g gels we have with a locker where she would only need to squeeze. (or energy chews already unwrapped on the box in the frame)
  • We might have given her superconcentrated hydration bottles.

Changing the plan considering the weather conditions

52:28 -

  • If it is much colder than you expect, you will drink less fluid than regularly, but you must keep up your carb intake.
  • Do not force yourself to drink high volumes of fluid in those conditions.
  • Moreover, there are few cold triathlons. People living in cold countries have some experience working out in those conditions.
  • The psychological effect of being cold in the race is something we do not deal with often.
  • It is challenging to manage if you get too hot, but people know that feeling and are more geared up for that.
  • If it is cold, keep pushing and eating to keep yourself warm. 

General observations from the races

55:12 -

  • The low-carb intakes usually affect recovery, and Emma felt she took much more time to recover from the race.
  • Training in a low-carb state will be detrimental to performance and recovery, which highlights she pushed deep to finish where she finished.
  • So, remember that recovery is part of the process, so pay attention to nutrition on race day or in training.

Precision Fuel & Hydration future projects

57:22 -

  • As mentioned, we will support a PhD student to look at fluid and sodium intakes in different environments for ultra-endurance events.
  • It has a duration of three years, so for everyone based in the UK, we will gather participants to be part of the research study. (triathletes, runners, cyclists - fit athletes that can last 4-5h in a heat chamber)
  • Participants will test their sweat/sodium concentrations and will probably know a bit more about their physiology. (VO2max and lactate tests)
  • So, watch our website and newsletter to learn more about that project.


Bernardo Gonçalves

Bernardo is a Portuguese elite cyclist and co-founder of SpeedEdge Performance, a company focused on optimising cycling and triathlon performance. He writes the shownotes for That Triathlon Show, and also produces social media content for each new episode.

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