Nutrition, Podcast, Racing

Race-day fueling and The Core Diet with Jesse Kropelnicki | EP#40

 July 14, 2017

By  Mikael Eriksson

Race-day fueling and The Core Diet with Jesse Kropelnicki | EP#40

Fueling is the fourth discipline in triathlon, but in long-course racing, it's no less important than swimming biking and running.

Jesse Kropelnicki, elite coach and founder of QT2 Systems and The Core Diet, has worked with a great number of athletes and made race-day fueling their strength using the principles of The Core Diet. If you've struggled with race-day fueling, you'll walk away from this interview with a clear path for how to make it right.

In this Episode you'll learn about:

  • How to think about nutrition in your day-to-day life
  • How to reach your racing weight
  • How to fuel in training
  • What the fuel window is, and why it is so important
  • How to fuel in races


About Jesse Kropelnicki

02:08 -

  • ​An engineer by education.
  • Started triathlon and endurance sports in 1997.
  • Was into weightlifting where he learned about nutrition, which he then carried into triathlon.
  • Started QT2 Systems in 2005. It now has several brands including: QT2 Systems (detailed triathlon coaching for high-level athletes), OutRival Racing (triathlon coaching), The Cycling Formula (cycling coaching), The Run Formula (running coaching) and The Core Diet (endurance sports nutrition).
  • Released a new book last January 2017 titled “The Endurance Training Diet & Cookbook” which covers how to properly approach race day fueling and day-to-day nutrition as an endurance athlete. It also contains recipes for these.

How do you start the nutrition conversation with endurance athletes?

​04:24 -

  • I start with the day-to-day nutrition because this is the foundation as an athlete.​
  • Then we have the fueling piece which is what you do prior, during, and after a training session or race.

How should triathletes go about day-to-day nutrition?

05:14 -

  • ​There are differences based on the body composition of the athlete and where the athlete wants to go.
  • There is an optimal lean BMI for each kind of sport.
  • BMI or Body Mass Index is a measure of how much you weigh relative to your height, but it doesn’t distinguish muscle and fat content which is important to triathletes.
  • So BMI for a triathlete is not a good measure on its own, but if you combine BMI with body fat percentage it will tell much of the athlete’s muscle content.
  • Example: an athlete who weighs 150 lbs. at 15% body fat and we need to reduce the body fat to 5%. This means a short-term weight loss of 10% of just body fat. 10% of 150 lbs. is 15 lbs. Therefore the race day weight is at 135 lbs. at 5% body fat. We assume that we can attain this body fat percentage by manipulating the diet to lose only body fat.
  • Then we take the 135 lbs. assumed race day body weight which is called the lean adjusted body weight to then calculate BMI.
  • The formula for BMI:
  • Now, BMI tells you more about the athlete’s muscle content because we have taken out the fat content. It now tells about only the athlete’s muscle content which is important to the athlete and the coach to understand where the limiters may lie.
  • Every sport has an optimal lean adjusted BMI. In triathletes:
    • Female: BMI = 20
    • Male: BMI = 21
  • For marathon
    • Female: BMI = 18
    • Male: BMI = 19
  • As we talk about day-to-day nutrition:
    • We have the short-term race weight in which we manipulate the body fat percentage to get to over a short period of time.
    • Then we have the long term race weight where we're trying to get to those optimal lean BMIs and remove strength as a limiter.
    • In some cases the limiter may not even be getting down to a small enough lean adjusted BMI, but rather that the muscle content of an athlete /typically males) is more weight that the athlete needs to carry for the sport of triathlon, which actually slows them down.

What is the normal BMI and body fat percentage for beginner triathletes or everyday age-groupers?

12:02 -

  • Males usually have 12-13% body fat.​
  • Females usually have 18-22% body fat.
  • Removing body fat that isn’t required for health is going to be a massive impact on race day performance.
  • Example: a male at 12% body fat can go down to 6-7% body fat given the age and demographics. This is about a 5% body fat loss.

    If they weigh 150 lbs. then that’s a loss of 7-8 lbs. which is worth 7-8 minutes savings in a half-distance Ironman, and 14-16 minutes time savings in an Ironman.

What needs to be done in day-to-day nutrition to get an optimal BMI and body fat percentage?

13:45 -

  • The Core Diet forces or encourages athletes to focus on the core foods in any period where they are not working out.​
  • These core foods are lean meats, fruits, vegetables, nuts seeds, legumes, and dairy. What is not in here are grains and refined sugars.
  • These core foods have a significant nutrient density to keep blood sugar very stable throughout the day. These are the foods that the human body is meant to eat for many years.
  • Then during training or races, this is where the grains and refined sugars come in where they serve a very specific purpose which is to fuel that training session or race event.

What are some potential negative outcomes if you are not getting a nutrient-dense diet?

16:05 -

  • If you don’t have an optimal nutrient density between workout sessions, those recovery periods will take longer.​
  • You will not be able to apply as much training load over a longer period of time which will negatively impact your performance during the race.
  • It’s detrimental to the immunity of the athlete. They’re more likely to get sick and therefore apply less training load.

What are your guidelines for macronutrients?

17:57 -

  • We have some workout windows where the athlete can have grains and refined sugars for fueling. These are the 1-hour pre-workout window and the post-workout window that is the same length as the workout.​
  • The post workout window consists of immediate post-workout refueling (your recovery drink) and then further refueling after that for a window that's a bit longer.
  • If you do well, you replace 50% of your energy expenditure with during-workout fueling, 25% with your recovery drink, and the final 25% in the rest of the post-workout window.
  • On a typical recovery day when there are no workout sessions, the ratio of carbohydrate is only 35-40% as there are no workout windows. The athlete only focuses on the core foods which tend to be low on carbohydrate.
  • Conversely, on a workout day, the carbohydrate percentage is suddenly 60-70% because you now have your pre-workout window, during-workout fueling, and post-workout window.
  • The beauty of The Core Diet is that it automatically scales the macronutrients as long as you stick to these windows.
  • Overall, on a recovery day or a very light training day, you will have 35-40% carbohydrates, 30% fat content, and the remainder is 30% from protein.
  • On a training day, you will have 60-70% carbohydrate, 15-20% fat and 15-20% protein.
  • For athletes who want to track macronutrients very carefully, you can go download The Core Diet Macronutrient Calculator from the App Store.

How long does it take for the body to digest and absorb carbohydrates?

21:23 -

  • ​The glycemic response of a higher glycemic carbohydrate like a grain is about an hour. It peaks out at about 30-40 minutes and then it starts to drop off after that. This is why we use the 1-hour pre-workout window.
  • Avoid any fat, fiber, or protein during the 1-hour pre-workout window because they dilute the blood sugar response of any carbohydrate that you may have.
  • This is why we eat the core foods which are high in fat, fiber, and protein in-between workouts to keep the blood sugar stable.
  • This is also true for the post-workout window. Athletes should only eat foods high in carbohydrate and avoid those with high fat, fiber, and protein content because we want to get the blood sugar up as quickly as possible as well after the workout.
  • Focus on clean carbohydrate that is very high glycemic and a good quality easily-digested protein source somewhere in the 3:1, 4:1, or 5:1 carbohydrate to protein ratio.
  • The product that we’re using most right now is the Klean Athlete’s Recovery Drink which has a 4:1 carbohydrate-protein ratio.

How to get to your racing weight

24:54 -

  • If you’re an athlete that wants or needs to lose body fat, the tweak that you need to make to the approach is to remove the post-workout window fueling.​
  • The post-workout window fueling is there to replace the 25% of the expenditure. So if we remove this, this will create the deficit to reduce the body fat.
  • Do not mess with the during-workout fueling because this is the one thing that allows us to train hard.

How do you approach in-training fueling at The Core Diet?

26:10 -

  • We’ve worked with 2000-3000 athletes developing detailed race-fueling plans. And I can say that in-training fueling is the number one limiter in long course racing.​
  • The biggest changes that we make with an athlete’s fueling are to make sure that they’re getting enough fluid and sodium.
  • Most athletes drastically underestimate the requirements in these two areas.
  • The easy way for an athlete that is racing a half Ironman or an Ironman event to make sure that they’re drinking enough is simple. You need to make sure that you pee at least once in a half Ironman on the bike and at least twice on an Ironman on the bike.
  • If you will not do these two things in your races then you are not going to perform to your potential.
  • As long as you’re drinking those fluid requirements and utilizing a sports drink that has proper sodium content, then you will fulfill the sodium requirements.
  • Proper sodium content is 500-600 mg per 24 oz.
  • So the ideal sports drink should have 42-52 grams of carbohydrate and 500-600 mg of sodium per 24 oz, which is a standard bike bottle size. This is the golden rule.
  • So if you simply drink that sports drink commensurate with the sweat rate and utilizing the pee guidelines, you’re probably going to take care of the sodium requirements as well.
  • Athletes make mistakes here by not drinking enough. Therefore, they are dehydrated and not providing enough sodium. Or they may drink enough but use the improper sodium content sports drink and therefore don't get enough sodium.
  • Quickly running the math on this, let’s say most athletes are drinking 2-3 bottles on the bike in a half Ironman yet their sweat rate requires 4-5 bottles. Now, they’re approximately 3 bottles short on the bike. If each bottle is supposed to have 500-600 mg of sodium, they’re now short of 2000 mg of sodium just on the bike. Then they go ahead and grab a sodium supplement that has 80 mg per capsule and they take 3-4 capsules and then they think they have fulfilled the sodium requirements. They’re not even close. It’s still 1700 mg of sodium lacking. So you can see how quickly these deficits add up.
  • The other mistake that people make is that they go and drink water on the bike which does not supply any of the nutrients that you need which are the carbohydrates and sodium. We never ever recommend that athletes drink water. You drink a sports drink that has the proper sodium content in every training session and in every race. Water is blank and it puts the blood sugar on a roller coaster.

You advocate using only sports drinks during training. Does it only apply to long or hard workouts? Are there any exceptions?

31:24 -

  • No, there’s no exception. It’s every single workout no matter what.
  • The only thing that is somewhat of an exception is if you’re an athlete who only does sprint distance racing or Olympic distance racing. The race fueling limiter in these cases is much lower because the onboard fuel source has enough reservoir to cover the race.
  • But if you go beyond these, a sports drink is a must because, for most athletes, their primary limiter on race day is their ability to handle what their body requires. They think that because their body requires a certain amount of carbohydrate, sodium, and fluid that they’re magically just going to be able to handle it.
  • Athletes who have a higher sweat rate, many times need a year to train their gut to actually handle what their body requires. On the extreme end, I’ve worked with high-level athletes that in a race like Kona have required 24-26 bottles. I even had an athlete at Ironman Texas one year who drank 25 bottles on the bike and didn’t pee because his sweat rate was so severe. He had trained himself over many years to be able to handle that.

How can athletes find out their sweat rate?

34:29 -

  • The best method is the real world method which is done by reviewing a race that you’ve done, determine how many bottles you had consumed on the bike, and how many times you peed and what the environmental conditions were.​
  • For example, if you drank 3 bottles in an Ironman 70.3 at 80° F and you didn’t pee, this is an indicator that you need at least 4-5 bottles. Then you can quickly start to apply this in training where you are doing a 3-hour bike ride, wherein you should be able to pee at least once during that ride. If you haven’t, then you probably need to drink more. And again, it needs to be a sports drink with the proper sodium content.
  • This is the starting point of building a race fueling plan where you determine your sweat rate, you supply the proper sports drink that is commensurate with the sweat rate, and then you figure out based on your size how much carbohydrate you need per hour – a lot of this is going to be supplied by the sports drink for starters, anything else that’s required is going to come in mostly through gels with the proper sodium content.

How do you determine the carbohydrate you need per hour based on your body size?

35:32 -

  • There’s a lot of information that I have in the book about exact quantities in the carbohydrate load, exact quantities in the race morning breakfast, exact quantities on race day.​
  • You can grab the book at Amazon or you can go to USA Triathlon where I’ve recorded several webinars there that cover this topic.

Carbohydrate loading and race-morning breakfast

36:27 -

  • The carbohydrate load is important. We generally like to have the carbohydrate load primarily a day before the event for any race that is Olympic distance is longer.
  • That carbohydrate load is somewhere to the tune of 10 times the athlete’s weight in kilograms in terms of grams of carbohydrate. We like to get 50% of that quantity in before noon the day before and then taper the back half of the day. The largest meal is always at breakfast the day before.​
  • In general, we stay away from fat and protein on that day and stick with foods that are very bland, totally opposite of the core diet foods that I mentioned because they contain fat, fiber, and protein – things we want to avoid as part of the carbohydrate load. The whole idea here is to wake up on race morning in a position to handle the race morning breakfast and the race day fuel. So that’s why we taper things the back half of the day.
  • Then the race morning breakfast itself, we generally want to have that 2.5 - 3.5 hours before the event. Again, we stay away from a significant amount of fat and fiber. We do supply a little bit of protein in the form of either whey protein powder or egg whites 15-20 grams. We’re big on using sweetened applesauce as part of the carbohydrate content which tends to do a good job in cleaning the system out.

What is your take on metabolic efficiency as it relates to low-carbohydrate diets?

38:21 -

  • Metabolic efficiency is the approach of trying to train an athlete to be able to operate or exercise utilizing more fat than carbohydrate. And the theory is that you will, therefore, be more efficient, require less fuel, not have to carry as much, etc. I’m not an advocate of this approach.​
  • The reality is that most triathletes are so stressed in different ways. So the general approach that most people take to try to achieve the so-called metabolic efficiency is not to fuel during many or some of their workouts. So for these athletes, it’s almost like a death sentence to their system because they’re already overstressed. So now we’re taking an already overstressed system and applying more stress to it by not feeding it.
  • If we look at a triathlete who has a very low muscle content - that low lean BMI, now not eating is a lot worse because the body is going to rip through muscle content as a way to fuel itself.
  • In the fueling side of things, we have a concept called fueling window. The fueling window is the difference between what your body can handle during race day and what your body requires.
  • My approach is to train the body every day to handle more and more fuel. True, you might require a little more fuel but the reality is, the rate at which you’ve trained your body to handle more fuel is larger than what your body requires. Therefore, your fueling window or your window of insurance is very large. This is what you want as you’re sitting at the starting line as an athlete.

Is there anything in triathlon or nutrition that you’re excited about related to new technology or new training protocols?

43:21 -

  • ​The latest stuff that I’ve been looking at is around cycling cadence and how to use that to address athlete limiters. Instead of getting into the argument that an athlete should be this and that, the reality is there’s a probably a place where athletes should be that is specific to them and how to address that.
  • I’ve been working on a couple of projects to implement throughout our coaching organization to be repeatable. Example, an athlete has a limiter X and therefore this is the cadence that they should maybe utilize for these types workouts to address that limiter.
  • There is no “one size fits all” for triathlon. Everything should be very specific to each athlete.

Rapid fire questions

46:31 -

Favorite book, blog or resource related to triathlon: 

Favorite piece of gear or equipment:

  • Heart rate monitor. However, as I said there’s no one answer. When it comes down to utilizing pace, power, or heart rate to dictate training load, the reality is that your body doesn’t know the difference. It’s just the training load. Whatever you think can help you apply the intended training load in the most accurate way is the right answer at that point for that person.​

A personal habit that helped achieve success:

  • Making a to-do-list and marking the few most important tasks for each day with stars in order to get them done first.​

Field Work Nutrition Primo Smoothie

51:36 -

  • ​I’m also involved in a recent project called the Field Work Nutrition Primo Smoothie. We created this nutrition product that fit the principles of The Core Diet. This also provides the nutrient density which we always see that is deficient in endurance athletes. We can send you a sample that you can try. It’s a great day-to-day meal replacement product between workout sessions.

Links and resources

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Mikael Eriksson

I am a full-time triathlon coach, founder of Scientific Triathlon, and host of the top-rated podcast That Triathlon Show. I am from Finland but live in Lisbon, Portugal.

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