Pre-Diabetes Pitfall for High-Carb Athletes - Study Advocates Low-Carb Regimen for Ultra Endurance

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Pre-Diabetes Pitfall for High-Carb Athletes - Study Advocates Low-Carb Regimen for Ultra Endurance

Hey, Athletes! Pre-Diabetes Pitfall for High-Carb Athletes - Study Advocates Low-Carb Regimen for Ultra Endurance  Episode of The Garage Gym Athlete Podcast is up!

Pre-Diabetes Pitfall for High-Carb Athletes - Study Advocates Low-Carb Regimen for Ultra Endurance


  • Jerred discusses High Carb diets and Endurance
  • Jerred goes through a study that discusses incidents of diabetes and high carb diets
  • He gives his on take on fueling for runs, workouts, and events
  • And A LOT MORE!!

Diving Deeper…

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To becoming better!

- Jerred

Podcast Transcript

Jerred: Should you be slamming carbohydrates before a run or endurance activity or even before your workout? How about during a run or during your workout? Should you be gulping down gels and sports drinks to fuel yourself for that performance? And a bigger question, If you are implementing these strategies or you are looking to do endurance races, is the current nutritional frameworks for endurance actually leading people to be pre diabetic and actually the number one reason why most people DNF endurance races?

So if you want to know more about pre and Intra workout nutrition for endurance races specifically, that's what we'll be getting into today. This is the Garage Gym Athlete Podcast, and we're here to build autonomous athletes and put phenomenal programming into every garage, basement, and spare bedroom out there.

I'm Jared Moon, and I'm with Jill Courtney. We are strength and conditioning coaches who have turned over 20, 000 people into Garage Gym Athletes over the last decade. And we're here to reduce the information overload that exists in the health and fitness industry today. We're going to do that by covering relevant science and give actionable takeaways, not only from the data, but from our years of experience.

So let's dive in.

So I feel like I am picking up where I left off several years ago when I was doing more endurance training. Uh, I'm, I'm walking down this path that I've already been down, and this path, getting back on the path, there are some weeds on the path, there are some logs on the trail, whatever, but, you know, I'm clearing those things out, and I still see a lot of the places I've already been, uh, and that, those places are being, fueling for endurance performance, I've already spent a lot of time and research in this area, But having, having taken a break from endurance training, uh, you know, for a long time now, a couple of years, I haven't looked at a lot of the research recently.

And there's been a lot of cool new things that have come out since I kind of pressed pause on this stuff back, let's say 2018, 2019. And that's something I want to get into today as I'm starting to train for more endurance style races. And as, as I'm doing this, it's easier for me to come in and look at it.

As someone who doesn't really consider themselves an endurance athlete, more like a performance consultant looking at what's currently happening in the industry. And as I start to implement strategies myself, what's a good idea, what's a bad idea. And two big things came up for me in my research, two concerns.

And, you know, what I'm looking at as I, as I look to do some endurance, longer endurance races, ultras, etc. One is runner's stomach. So, runner's stomach, if you didn't know, is the number one, it's reported that it's the number one, uh, you know, GI distress is the number one causes, number one cause of a DNF at ultra endurance races.

So, GI distress, stomach issues, is the number one reason people do not finish longer races. And. There are a lot of reasons for that, um, it could be improper fueling strategies, it could be not testing fueling strategies ahead of time, but another theory behind that is large ingestion of sugar, carbohydrates, and it just causing, uh, gut distress.

So there are supplements out there that say that they can, you know, get past this or whatever. But typically. I'm not going to say a supplement is the answer to all your problems. So that's the number one concern, runner's stomach. And the second one is pre diabetes, which might sound weird to be concerned about pre diabetes when we're talking about training.

And, uh, you know. Working out, but let's just go over some of the stats. So according to a CDC report, 86 million Americans are estimated to have prediabetes, with 90 percent unaware of their condition and without lifestyle changes like weight loss or moderate physical activity, up to 30 percent of them may develop type two diabetes within five years.

While exercise generally improves fat oxidation and insulin sensitivity, remember those things, very important, fat oxidation, good thing, insulin sensitivity, good thing, thus lowering type 2 diabetes risk, research indicates that 15 20 percent of individuals do not show improved glucose tolerance or insulin sensitivity following exercise interventions.

This highlights the variability in response to exercise and diabetes prevention. What that's saying is there's at least 15 to 20 percent of people who have been tested that even though they exercise don't seem to respond to not being pre diabetic or diabetic, you know, exercise isn't a cure all. And that's how a lot of people feel, especially endurance athletes.

Endurance athletes feel like they kind of have a license to eat whatever they want, consume whatever they want, and it won't really matter, but I don't know if that's truly the case. So, Number one concern, like I said, uh, not, not necessarily an order of importance, but it's just, hey, how do I not, how do I, I don't want to be the guy who has a DNF on a race because of a stomach issue.

You know how bad that would suck to train, put all this time, effort, energy into what you're doing, and then you realize, oh man, it's just a stomach issue, ultimately, that, that got me. So I don't want that to happen to me as I delve into these longer races. And two, I've already been on a low carbohydrate diet.

Now, I came off of a low carb diet and went higher carb, and I had some blood work done, and my fasting blood glucose and my A1c were higher than I would like. And that was after coming off low carb, going on to moderate to high carb ish, you know, just kind of not caring about carbs. And then, that's where I ended up.

Now, I wasn't necessarily pre diabetic. But I was elevated from normal, and it was not something I was happy about, not something I was excited to see in blood work. And then that had me, like I said, rewalking a path I've already been down. And it remained reminded me of a conversation I had back in 2017 with Zach Bitter.

Now you can go to the Better Human Business Podcast. That's what it's called now, formerly the Better Humanology Podcast. If you want to listen to this conversation, the title of the podcast is Ultra Marathons Using a High Fat Low Carb Diet to Crush Endurance Training. and mental toughness with Zach Bitter.

And I remember all the fueling strategies that he used to maintain metabolic flexibility, being able to switch between fat oxidation and carbohydrate oxidation. So using fat for energy or using, um, carbohydrates for energy. And I started to dive in and I wanted to see, hey, what is that's back 2017, 2018.

What did, where, where are we at with the research? What has come out since then? And I found this very interesting study. It's actually a really good study. It's called Low and High Carbohydrate Isochloric Diets on Performance, Fat Oxidation Glucose, and Cardiometabolic Health in Middle Aged Males. It was published in Frontiers in Nutrition on February 9th, 2023.

So I'm quickly going to go over all the details of the study. So the study involved a group of highly trained middle aged male athletes who underwent... two 31 days isocaloric diet periods, either low carb, high fat or high carb, low fat, and a randomized counterbalance, counterbalance crossover design. Key outcomes measured included performance, substrate oxidation during exercise, continuous glucose, and cardiometabolic biomarkers.

So essentially, They had low carb, high fat, and high carb, low fat, and then they acted as their own control. So the same person would switch, and they would go through each one of these. Now, just to briefly gloss over the other things, because I don't want to bore anybody with every single detail, uh, they did peop have people follow these low carb, high fat, or high carb, low fart.

Low fat diets. The performance metrics, uh, there were no significant difference in performance metrics like the one mile time trial and repeated sprint protocol between these two diets, uh, physiological response, the low carb, high fat diet led to significantly higher fat oxidation rates. Something that you want particular.

particularly during repeated sprint protocols. Peat fat oxidation rates recorded for low carb, high fat were among the highest ever measured. Conversely, there were higher carbohydrate oxidations on the high carb, low fat diet, which makes sense. Body composition, no real change. Uh, now one of the interesting cardiometabolic, so cardiometabolic health, um, markers, and this will kind of like wrap it up.

The low carb, high fat diet resulted in reduced mean and median glucose levels and variability. Interestingly, 30 percent of the athletes on the high carb, low fat diet who had mean and fasting glucose levels consistent with pre Diabetes. Okay, so they, they showed the largest glycemic and fat oxidation response to carbohydrate restriction.

So meaning they, they saw a great response to low carb once they switched, but 30 percent of the athletes in the high carb diet, which is kind of consistent with what I was going over over the CDC data. 30 percent of the athletes, even though they're training and they were on the high carb diet, their blood glucose levels were consistent with having prediabetes.

So again, this exercise does not save you if your nutrition sucks or if your fueling strategies suck. It does not give you a license if you're an endurance athlete to eat whatever the hell you want and shove anything in your mouth during a race or before race or after race. And so this study really challenges the traditional view that higher carbohydrate intake is superior for athletic performance, even during high intensity exercise, which is something I got hung up on back in the, back in the years when I was looking at this stuff is like, it seemed like low carb was great for, uh, you know, very like low zone two stuff, but it wasn't great as intensities increase, but that seems like this might be turning a little bit.

I'm not fully convinced, but it does look like that is headed in that direction. So this study is saying, Hey, Low carbohydrate and high carbohydrate are great for performance, so I'm not saying one's better than the other, but when you look at just the pre diabetes, 30 percent of athletes on the high carb diet ending up with pre diabetes, that's kind of crazy.

Now, I may have a predisposition to this, like I don't necessarily have family history of diabetes that I'm aware of, like my parents don't, I'm not aware of my grandparents having it, or aunts and uncles, but I also don't know every single thing about everyone in my, My family, so maybe I am predisposed to this to some degree.

But I know for a fact, if I just go on a higher carbohydrate, higher carbohydrate diet, that's not good for me. So I, looking at this stuff, am very aware of like, hey, how do I avoid runner's stomach? Then also, how do I not get diabetes by trying to ingest all, you know, all these gels during a run or a bunch of carbohydrates before I run?

And is it even necessary? And so the goal that we should be after, any athlete should be after, whether you feel like you, you know, you're in the same boat of me, boat as me or not, is that we should be looking for increased fat oxidation during exercise. So, and one way to do that is to lower your dependence on carbohydrates.

So, no matter who you are, I think that it's a good idea to try and get more fat oxidation. Whether you're like, if you're like, I'm not concerned with pre diabetes or runner's stomach. Well, you should be concerned with having fat, higher fat oxidation. It's just going to be better for you, uh, higher insulin sensitivity, those kind of things.

ultimately all good metabolic markers. So if you're just looking to be healthy, these are things that you should be interested in. Then also, if you're an endurance athlete looking to maybe have an alternative fueling strategy, also something that you want. So fat oxidation, it can increase your endurance performance, improves your energy management, gives you metabolic flexibility.

So the ability to switch between carbohydrates and fat, um, you get reduced fatigue and recover recovery time because when you're operating in. Lower zones and more fat oxidation, less carbohydrate production. You're not going to have as much lactate, you're going to have less fatigue overall. And there are a lot of health benefits with fat oxidation.

So enhanced fat oxidation can also have long term health benefits such as improve insulin sensitivity and reduce the risk of certain metabolic diseases. Now, can you actually have high performance on, you know, world class endurance performance on a low carbohydrate diet is a lot of, a question a lot of people ask.

Now, Zach Bitter specifically, the guy I interviewed that you can go listen to, uh, let's see some of his stats. He did, he has the 100 mile treadmill world record, which is crazy. Had him punching out 7. 18 minute miles over 12 hours in 2019. Zach had a hundred mile world record, had him running sub six 50 minute miles for over 11 hours.

Dr. Dan Plews. These are all low carb athletes. 2018 Kona age group course record had him run a two 50 marathon, which translates to highly consistent sub seven minute mile price paces across the whole run leg. Matt Kerr, who's another low carb athlete, 2021 Age Group Ironman World Championship victory in St.

George, Utah, delivered the fastest run leg of all age groupers, 257. 57 on a course with 1, 400 feet elevation gain in temperatures in 80 to 90 degrees throughout the bike run legs. So, so you can absolutely do this. Now, let's get into the takeaway of what you should do with this information. Should you be staying away from...

Carbohydrates. Ultimately, I do think to some degree you should now. I'm not a hardcore low carb guy, and I'm not like a carnivore guy or a keto guy. I'm not really any of that. I'm looking for fueling strategies that aren't going to lead to, uh, you know, other health problems like being diabetic by consuming just too much sugar.

Um, and then also, you know, I don't want runner stomach. And another way to do that is consume less sugar and rely more on fat oxidation as you're doing these endurance races. So I'm not like in that camp, I'm not one of these hardcore guys who thinks you should be low carb and, and keto and all that junk, but there are some basic things that you can do.

I can do to benefit from, you know, fat oxidation, having more fat oxidation, relying less on, on. Uh, you know, carbohydrates always needing to take in carbohydrates to, to run another 30 minutes or whatever, you know, it gets ridiculous if you get in that pattern, uh, one, increase fats in your diet and decrease carbs.

Now, let's not even talk about percentages necessarily. Now, when you look at the low carb and high carb, uh, diets, The high carb guys were, were taking in around like up to 130 plus grams of sugar. So they would go down to 120 up to like 170, something like that. A ton of sugar, and this is just sugar, not even just carbohydrates.

And the amount of sugar a, uh, low carb person would have would be about 15 to 20 grams of sugar a day. That's not a lot of sugar. So these are kind of extremes and I don't think that she should go in any direction and most of us listening to this We're not in the extremes. So what can we do? Well, just increase our fat intake healthy fats and decrease some of our carbohydrates.

Can we switch out, you know having You know, an avocado with lunch as opposed to a bag of potato chips, simple choices like lower carbohydrates, a little bit increased fat so your body can utilize more fat during exercise. You can also use directly MCT fats in your diet and for fueling strategies, maybe try just small amounts of this pre workout.

Um, and that would be MCT oils that have C8 or the C10 forms specifically because they're going to be faster digesting and your body can actually utilize them for energy. So again, it's very small amounts because they're. It can, um, if you have large amounts, it's, it's, you will know, uh, with some GI symptoms there, uh, it'll all come out, you know, needless to say.

So take in very small amounts of that, like tiny amounts, pre run, see how you feel. Now another easy way to do this. Increase fat oxidation is just to try some fasted training. Uh, there's a lot of, you know, research on the fact that fasted training will increase fat oxidation. So, don't hear what I'm not saying.

I'm not saying, hey, go do fasted training because you're gonna get shredded and lose all this body fat. I'm not talking about body fat or looking a certain way. I'm talking about fuel sources. So if you train fasted, your body will use more fat as an energy source. And I'm not talking about how you look and losing body fat.

It's just going to use body fat as a fuel source. Now, from a health and performance standpoint. That's awesome, because our body is sparing the glycogen, the stored carbohydrates, and it's utilizing more fat. We want to use more fat so we can preserve our glycogen for when we need it. That also becomes very important in a race, as opposed to just constantly fueling yourself with sugar, you know, a sugar hit every 30 to 60 minutes.

That's not the habit you want to get into. And when you have increased, uh, fat oxidation, You can, you can spare glucose, and like I mentioned earlier, you can recover faster. So this is something that's, that's really good, and it's really good overall for your metabolic health to have increased insulin sensitivity and fat oxidation, and you can do this through fasted exercise.

Very easy thing to practice and train with, and it might be hard at first if you've never done any of these things. You'll have to try a transition strategy. I'm actually transitioning right now back to a... low to moderate carbohydrate diet. Again, I'm not a keto guy. I'm not a super low carb guy, but I want to increase my fat oxidation.

I want, I don't want any reliance on uh, gels or massive amounts of carbohydrates pre run or during a run. I don't think it's necessary. While you absolutely can perform with those things, I'm not saying one's superior to the other. If that's the way you do it and you're fine and you've had your blood work checked and you're good, you don't get runner stomach, like whatever.

You keep doing what's best for you. But if you want an alternative strategy, you want to try something else and be able to run longer and perform better and be healthier, this is a definite science backed opportunity for you and strategy that you can use in your day to day life. So give it a try. Main takeaway, try and reduce some carbs, add some fat, try some fasted training.

Pretty simple, but also a lot of food for thought if you're going to dive into fueling for an ultra or any kind of endurance race. So for all of our garage gym athletes out there who are in the training, doing the stuff, thank you so much. If you want to be a part of our training, go to garagegymathlete.

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