The Ultimate Guide To Combining Fasting and Exercise: Everything You Need To Know.

Welcome to the BenGreenfieldFitness.com podcast. We provide you with free exercise, nutrition, weight loss, triathlon and wellness advice from the top fitness experts in the nation. So whether you're an Ironman triathlete or you're just trying to shed a few pounds, get ready for non run of the mill cutting edge content from BenGreenfieldFitness.com.

Foreign.

Hey folks, it's Ben Greenfield and in the past we've had some interesting podcast discussions about fasting and specifically the combination of fasting and exercise. For example, last year we had Dr. Peter Attia on the podcast and he talked about how he's turned himself into a fat burning machine by fasting for 24 hours than going out and doing these monster five to six hour bike rides. We talked to Dr. Dominique D' Agostino a few months ago on this podcast about ketosis and how he's working with people like Navy Seals and extreme athletes in the U.S. military to kind of get their bodies into a state of ketosis for enhanced endurance adaptation specifically. And I've even talked on this podcast about myself and how I utilized quite a bit of fasting exercise protocols and ketogenesis to prepare for Ironman Canada and the Ironman Hawaii World Championships last year. But when it comes to fasting and endurance performance specifically, there is one person who I've followed quite a bit over the past year as far as paying attention to the protocols that he is implementing, especially when it comes to combining fasting and exercise. And some of the things that he's written and his name is Barry Murray. Much of what he's written I've seen over on Dr. Jack Cruz's forum. And if you're not familiar with Dr. Jack Cruz, he's also been on this podcast before and talked quite a bit about ketosis and kind of enhancing the body's ability to naturally burn fats as a fuel. And Barry has been very active over on that forum and has really, in my opinion, flown under the radar when it comes to being one of the world's true experts as far as how to successfully do something like fast without destroying the body and also be able to do that and be a competitive athlete. So Barry specifically is a performance nutritionist and he specializes in endurance sports. He has a degree in chemistry and a master's degree in sports nutrition, so he really knows what he's talking about. And he has worked with professional cycling teams, triathletes, distance runners. Last year he worked as the sports nutritionist for the BMC Professional Cycling Team Which I know many of you are familiar with. He's a competitive endurance athlete himself. He races in ultra marathon events and actually represented his country at the 2011 World Ultra Trail Championships. And he's won many ultra trail marathons. He placed second at one of the UK's toughest 100 mile Ultras. He set national records for trail routes all over the world. Dublin mountains. And he's done a lot of this basically in a fasted state and also a state of ketosis. So, Barry, thank you so much for coming on the call today.

Thanks for the introduction, Ben.

Well, let's jump right in. And by the way, just to clarify, because I don't think I mentioned this exactly, which city and country are you based out of now?

I live in the Tuscany Valley just outside Florence, in a small town about one hour just outside Florence.

Okay, gotcha. And originally you're from where?

So originally I'm from Dublin, Ireland.

Gotcha, gotcha. Dublin, Ireland. That's the accent, folks. So, Barry, let's first delve into, before we get into kind of an overview of the mechanism and the function behind what goes on when you train in a fasted state or you race in a fasted state. Can you talk about your history, how you got into doing what you do, especially with the experiments that you're doing on yourself and, you know, the protocols you're using with the athletes that you coach and kind of your philosophy when it comes to nutrition and how you've used it yourself?

Okay, yeah, sure. I guess I started about five years ago, kind of just after I did my masters. I started just looking into a few things related to depleted glycogen depletion. And I started looking at fat, just some of the basic stuff on fat adaptation. And I just started looking, looking at the whole, the whole thing with insulin. So I started kind of saying to myself, well, maybe if I want to become fat adapted, maybe going out on my long rides or my long runs in the morning, it might be better if I suppress or not cause an insulin response. Because that was my basic understanding at the time, is that insulin suppresses fat oxidation. So I said, well, if I eat a boat of porridge or a boat of oatmeal, as you call it, in the morning, that's probably not going to be the best thing for me if I want to completely open up my fat pathway, fat oxidation pathway. So the very kind of first thing I did was I just went out on my long weekend ride on a Saturday morning with just coffee or, and just not eating. So that's how I kind of started off. And it's kind of important to emphasize how long I've been doing this for. So it's kind of like about five years ago when I started fast at state training. And I built that up then in terms of my training over the years. And I just built it up from going out in the morning on a long ride, which I first started doing by gradually kind of working up to doing some, maybe an easy two hour ride, to going up to three, four hour rides and also phasing how I used to eat on the bike. For instance, I might eat after the first hour. And then I said, right, let's try after a few months and try and eat after the second hour and then keep on always pushing out the boundaries basically. And then it was just natural for me to do this with running because most runners will know that, you know, if you're going out for an early morning run that generally you just don't, you don't want to have anything sitting in your stomach before you run. So I was going out and doing long runs and I just didn't want to have, just didn't want to eat. But I was also very aware of the whole mechanism behind it in terms of the fat oxidation, insulin and what I was switching on. So it started off with training and then I started racing ultramarathons. And obviously my knowledge with nutrition and biochemistry and hormones and everything else was growing at the time. And we're starting to realize that everything that is common is usually wrong. So I was kind of flipping it, turning everything upside down in terms of what I'd been taught a lot in the textbooks in college. And I was starting to look kind of deeper into things and I realized that the adaptations that were coming from what I was doing were huge. So, you know, look into things like the enzymes that switch on fat oxidation and the transporter proteins, etc. Etc. And I was realizing that this was really improving my whole, the whole adaptation procedure. And then I started racing ultramaritans. And the ultramaritan events were kind of anything over 50km in distance. So between 50 and 200k would be the kind of distance I was running I still am. And I started applying the same principles of my training to actual racing. I was turning up for these ultramarine events while everyone else was eating bowls of cereal and sports energy bars and rice puddings and various different things. I just brew a coffee and have a coffee and then get to the start line and run. And I was doing well. I started doing well at these events. And so I've done almost about 20 of these events now over the last three years and I've won a few of them and I've placed kind of usually in the top 10 in most of them, I suppose. I mean, to give us some recent, I mean, last year I ran 127k race here in Italy and like I said, 8 nothing before the race. I had very little during and it was 127km and I finished it in 14 and a half hours and I won the race.

Wow.

So that's how the training, fasting, the process of watching what I went through, what I tied that in with, of course, because nothing works in isolation, is I obviously tied it in with the whole, well, what kind of way of eating and what kind of food, what kind of diet suits this kind of training? And what suits it is the lower carb, higher fat kind of diet. So yeah, I changed my, I didn't change. I built my nutrition up to work in tandem with the whole fasted state thing. So that's, you know, the two of them have to work kind of beside each other, so to speak, or, you know, in tandem. So did a lot of work on looking into low fat, high, low carb, higher fat type diets. I looked at the timing, used all the things like carbohydrates, you know, backloading, cyclical ketogenic diets and just gradually, gradually, you know, improve. I just, I just was looking for every way possible in which you could increase the speed and the intensity and the distance at which you could go at without being as much as you can in the fat burning.

Yeah, yeah. Now before we get into the kind of the why you'd want to be in that fat burning zone and what the actual mechanism is and what's going on inside the human body when that happens, just so people can wrap their heads around what it looks like. Let's say that you were going to go out and you were going to do one of your mountain training runs or one of your ultramarathon training runs or even an ultramarathon event. What would your, your diet look like the day before and then what would it look like during the actual event?

Okay, well this again, this has changed over the years. So it took me a long time to actually to convince myself that not eating carbs the day before a race was going to be good for you. So just to very briefly tell you where I came from, I came from basically eating a kind of a lower glycemic index Type diet, carbohydrate diet, so low GI foods. And then I progressed to say generally having kind of a cyclical carbohydrate diet where I was, you know, some days eating low carbs, some days eating higher carbs. And then coming up to races, I was kind of generally eating a low carbohydrate diet. And then the day before I would eat things like sweet potato and fruits and some rice. But over the last kind of two years I switched that and I, I basically switched it to, you know, completely going low carb, high fat, or, you know, practically ketogenic. I mean, there's debates as to what, you know, ketogenic diets are, but basically what my day before a race would be. Now if I just, or, or generally any kind of training is basically, I've also adopted the whole pattern of less eating, less number of times a day is better for you. So generally I eat two meals a day. So my general training week will be. Or training days, like you said, a mountain run will be the day before. I will have done maybe a bike ride or a run the day before. And I don't eat breakfast, so I don't eat until lunchtime. So that's my first meal of the day. And that would be high fat, lowish carbohydrate meal. So it will be usually an omelette type dish with either fish or meat. And then the evening will be my dinner and that will be vegetables with either fish or meat again. And I will. Generally that's how I've been living for the last kind of two years with my training regime. And I'm training usually six, seven days a week. So I'm eating twice a day pretty much every day. The only time I change that would be for a race. I'll eat three meals. So I'll have, I usually do something easy in the morning, like a half an hour, an hour kind of a run. And then I'll eat breakfast. Breakfast might be an egg dish, I'll have lunch, it will be salad and fish. And then in the evening it might be meats with avocado and vegetables. And that's essentially what I've been doing for these big races. Pretty much under 100 carbohydrate. Sorry, under 100 grams of carbohydrate, if not less before the day before my race. This goes against every possible kind of text that I've ever read about preparing for. Preparing for a race.

Oh, yeah, absolutely.

That is what I've, that's how, what the level I've gotten to, but it's taken me a long time to get there.

Interesting. So what exactly? And of course I'll warn you, I want to definitely ask you about what you've noticed with your blood and your biomarkers and things like that. Only eating that very, very small amount of carbohydrate before going out and doing these monster training sessions. But what have you got to say as far as educating people on the mechanism and the function behind what's going on inside the body when you train in a fasted state versus when you go out and you train in the stereotypical, you know, kind of having that pre workout meal type of state.

Yeah. You know, I've had to explain this a lot because I find especially with, you know, experienced athletes, professionals, you know, athletes, if you've been doing something for a very, very long time and somebody comes in and tells you that you should flip it on his head and do it in the opposite way, it's very difficult for them to change or to do that. So usually explaining to people why and why it works and why it's better for you is usually the best thing to do. So I usually keep it kind of simple, but I usually always try to explain the mechanisms so that people understand. I start off with the simple case of just explaining the kind of insulin theory to them and that I simply explain that when you eat any kind of form of carbohydrate for breakfast in the morning, you're going to get an insulin response. And then I explain how insulin inhibits one of the several of the fat burning mechanisms. And I explain how hormone sensitive lipase, which is what obviously stimulates lipolysis is inhibited by insulin. I then explain how CPT1, which is the carnitine enzyme which transfers fatty acids into your mitochondria when insulin is released, that is suppressed as well.

And we're going to get insulin released with just about any protein or fat or carbohydrate containing meal in relatively significant amounts. Right?

Yeah, I think it's kind of like anything over 10 grams of carbohydrate is going to cause an insulin response. So that's not very much. And then obviously branched chain amino acids and whey protein powders and a lot of dairy is going to cause an insulin response as well. So generally, and I mean you can eat kind of maybe a very just it's very hard to eat just a 100% fat meal because you know, if you eat eggs in the morning, that obviously contains chain amino acids as well. So you know, there is the bulletproof coffee today that people are using and maybe that doesn't is going to have a very, very minimal instant release. But generally I always swear and kind of tell people, you know, the best fasted state training that you can do is to not put anything other than liquid, you know, water or tea or coffee down you. And you will get more adaptate, you will get the biggest, it will cause the most stress, but you will get the biggest adaptations from that.

Okay, gotcha, gotcha. So we've got basically an upregulation of lipase and an upregulation of carnosine, which is responsible for driving fatty acids into muscle tissue when we avoid that insulin spike in the day leading up to and also the day of the event. And you do so by limiting your meal frequency and by essentially as much as possible limiting any amount of carbohydrate in most proteins and amino acids.

Yeah, exactly, pretty much.

So you did this for five years and I'm curious about the steps to becoming fat adapted because you're one of the few people that I've spoken with who has stuck with this for long enough to kind of experience the full gamut of starting off from being a carbohydrate consuming endurance athlete to going through the initial stages of fat adaptation, to going up to kind of like this. You're at the five year mark. The reason I find that interesting is because, for example, when I had Jack Cruz on the podcast, when we talked about how to live like a polar bear and eat like a great white shark was the name of that episode. And by the way folks, for those of you listening in, I'll put a link to all the previous episodes we've done on fasting and ketosis and stuff like that in the show notes. But what he said was that he's under the impression that it takes anywhere from one to two years to even build up the mitochondrial density to be able to burn the amount of fatty acids necessary as a fuel to produce enough ATP or energy currency to support high levels of training or even life with fat adaptation or limited meal frequency. I'm curious what your thoughts are on adaptation and what you personally experienced.

Yeah, well, definitely the time component of this strategy is fundamental. I mean, if you are an athlete of any description and you think that you can go out and suddenly start working out without any food or without anything, it's just not going to work for you, certainly within the first few days, few weeks. And I don't think you will see, you know, you're not going to get to the, the kind of goal line until you've been doing it for months. As Jack Cruz has said it. I think it's, I think everything has to be put in context. I think if you're a general average person who's just training to be generally fit and doing, you know, going to the gym three times a week or whatever, I think it's going to take that, that person to be fully fat adapted probably a longer time. It's going to take a full time athlete who's been training all their lives. They will have a lot of the adaptations already before they even start doing any of this kind of fat adaptation, fasted state training stuff. So everything always depends on the context of the person and the individ. But I do definitely think in terms of my context and in terms of anyone who's kind of an experienced athlete or regularly competing and has a regular training regime, I think you're looking at a year minimum, 18 months. And I just think the longer you do it, the better it is. Because definitely it's about mitochondrial biogenesis. I think it's about mitochondrial efficiency as well. I think it's about up regulating. I mean beta oxidation is where fatty acids get converted to acetyl coenzyme A, which is a starting block then for the whole Krebs cycle. But if you look at beta oxidation, the burning of fatty acids, there's something like over 20 enzymes involved in that process of converting a fatty acid into acetyl coenzyme a. So there's 20 enzymes, I think there's like 15 transporter proteins also involved. So there's a lot of machinery that you have to make work, that you have to first of all build and then you have to make them work efficiently. So I think people don't understand the complexity of the shift that you are, the metabolic shift and the physiological shift that you are making the body do and all of the soldiers and the machinery, let's just call them, that you have to put in place and that you have to make work efficiently takes a long time. So the adaptations are really complex and you know, they relate to everything from, you know, upregulating enzymes, upregulating transport of proteins, upregulating cell signaling, upregulating mitochondrial efficiency and improving. I mean there's just, there's just a huge amount of physiological mechanisms that you need to build and actually create before everything starts working properly for you. And that's why it takes a lot of time and it has to be done in an incremental pattern as well. So you don't just start going out and doing five hour rides on empty and expect things to happen. You need to give the body acute kind of stresses over this long period and then you'll start seeing things happen. So that's what's happened with me and it's happened with a few, my other kind of close athletes and friends that I'm working with as well.

So, you know, you've worked with cyclists, you've worked with triathletes and with distance runners. Talk to me a little bit about the context in terms of the types of athletes and the sports that this works for. Because we have crossfitters and tennis players and bodybuilders and explosive power and strength athletes that listen to this show who are going to be curious about whether or not they could benefit from something like fasting or ketosis when it comes to more explosive type of efforts. Or even the people who are really dipping into glycolysis and higher intensity carbohydrate utilization for something like, you know, 5Ks and sprint triathlons and things of that nature. So who does this work for?

Okay, I think primarily who this works for. I'll kind of work backwards here. I'll answer the first part of the question. I think primarily who it works for are the long distance ultra endurance athletes. So cyclists and triathletes, Ironman in particular, and long distance runners. Everything I would say, when I say long distance I kind of mean long marathon and longer. So the reason being is because this whole fat adaptation thing and upregulating your whole fat oxidative pathway, it works for these kind of people because these kind of athletes, because these kind of sports are determined by how efficient and how economical you are. They're not about how necessarily about how fast you can go or how strong you can lift or how strong. It's not determined by your power or your speed. Basically it's determined by your running economy or your cycling efficiency. And also I think a crucial component of it is that your sport is pretty much a steady state sport. And this is why it probably works best with ultramarathon runners in general. Because we're running for a very long time and our pace doesn't fluctuate hugely. Our pace might, but our efforts doesn't fluctuate hugely. I mean, if you look at our heart rates or whatever, it's not going to fluctuate massively. So being in that steady state kind of energy production means that you can kind of get into the zone and when you're in the zone, you're in a constant state of energy production in the fat burning zone. So I think the best type of athletes that this is suited to are the long distance athletes, particularly the long distance athletes that have, are performing at a more or less a steady state. And the reason why I say that is because I've done a lot of work with professional cyclists and while fat adaptation and fasted state training is something that is very obviously good for them, they still require to be glycolytic. In other words, they still need carbohydrates to function because there are higher variations in the speeds at which they work at. So if you look at Tour de France cyclists, yes, they're doing long 200k rides, but there might be breakaways, there might be hill climbs, there is sprints, there's, you know, so there's a lot of variation in the power which they'll be using and the speed and the intensity which they'll be at. I also found this with professional, professional triathletes where there's lots of surges, whether it's on the bike, particularly on the bike where there's surges or runs where they're racing and have to break away or whatever. So this is really kind of a key point to make is that it definitely works for long distance athletes, but if you are in a sport like professional cycle or any kind of cycling that involves huge power fluctuations, then that's where the glycolytic component comes in. Does it work for tennis players, football players, CrossFit type people, etc. Etc. Yes, I think anyone can, no matter what your sport is, I think anyone can use fast, can train in the glycogen depleted or fasted state. It depends again, like you said, the context and in terms of your, if you're somebody who's doing two CrossFit sessions a day, five or six days a week, you know, there's some people doing crazy kind of workouts and that's when, because you're, they're constantly in a much higher intensity or state of energy production, whatever you want to call it, and they, they're going to run into trouble because they're not going to be able to keep up with their glycolytic demands. So I think anyone can. Anyone from any type of sport can get up in the morning, go out and do play tennis or play a match, or go to the gym, or do even a CrossFit session. The amount of times you do it depends on your situation in terms of how often you're Training. So yeah, I mean it works for everyone, works best for ultra endurance athlete.

Now a lot of people get concerned about the potential for playing with fire here in terms of the amount of fatty acids circulating in the bloodstream, potentially interfering with the thyroid receptor sensitivity to thyroid hormones or lack of glucose availability inhibiting like T4 to T3 conversion. Are you concerned about any of those issues? And as a follow up to that, do you test your own blood or have you found there to be anything that you're concerned about or that people should be aware of if they're combining fasting and ketosis with the extreme levels of endurance that you're doing?

Yeah, I mean like everything that you can have too much of a good thing. So certainly with something like fast, something like glycogen, doing big workouts, doing long runs or long cycles or long swims and. And if you're somebody who trains regularly, doing too much of this is going to catch up with you in terms of. I think what it predominantly affects is adrenals. So it causes a lot of adrenal stress. So this is one thing that you have to really watch out for. If you've gone into this too deep, if you've gone into the deep end too quickly and you might be able to do your run fasted, whether it's a two or three or even longer hour run or long cycle, you might feel okay at the time, but there was the adrenal stress that you're creating really backfires on you. And I'll give you an example. Two weeks ago I did it was a mountain, won't call it an ultramaritan, was like 45k long. So it's not very long for me, but I ran it kind of flat out and I did it in five hours. I did it, fasted and I ate very little during. I woke up in the middle, I went to bed and I woke up in the middle of the night with a pounding heart rate. It was my resting heart rates normally in the low 40s, kind of 40, 43, 44. I checked it and gone up to 66. So that's when I knew that what I did probably wasn't very good for me. So I think the number one thing you have to watch out for is the adrenal stress and the cortisol response. And cortisol response, as you know, is related to a lot of other things. So that's certainly one thing to look out for in terms of the low glucose and lower carbohydrate. Yes, I mean that's gonna potentially affect obviously things like thyroid. Have I looked at markers, biomarkers, myself? Not a huge amount because I'm just a big believer on going on feel. I think the most sophisticated monitoring system you have if you're a healthy person is yourself. So I kind of intuitively know whether, you know, whether I'm feeling a bit over trained, whether my cortisol is high. I'm intuitively aware of what my carbohydrate requirements are, even my fat requirements are, et cetera, et cetera. So I tend to listen to the body, you know, a lot. I'm kind of very in tune with it. So I've used testing on athletes quite a lot and I see so many conflicting, conflicting messages where, where an athlete might be shown low free, you know, low levels of free testosterone and then that same athlete will go and win a huge race, you know. So there's so many conflicting things I've seen with, with testing and then testing results that don't reflect how the actual person is feeling. So when you're a healthy person, you know, my analysis now of athletes when I work with them is like, you know, I speak to them and I ask them how they're feeling and you know, when I see low vitamin D or low testosterone, I'm not usually in a hurry to change things unless their performance and health really suffers.

So yeah, okay. All right. So as far as qualitative variables, I mean do you ever notice that like low libido, feeling more cold, anything that suggests you that, you know, in addition to like some of the adrenal type of issues that you hinted at, you know, needing to be careful with. Have you noticed any change in the way you feel when you're doing this fat adapted fasted stuff versus the carbohydrate based performance? No.

I mean the only thing, the physical thing that I've noticed that it has disrupted on a few occasions, it's definitely my sleep and it's definitely related to the adrenal stress. So you know, after big races or big training sessions and when I mean big, I mean I'm doing kind of crazy like 10 hour, 11 hour run kind of thing, I'll go, you know, my heart rate will be really high and I'll wake up with a pounding heart rate. So I think the adrenal stress is huge psych. You know, don't suffer from, don't suffer from cold or any other kind of health issues. It has a kind of, I think it has certainly kind of psychological when you're doing this for a long time. It certainly has kind of psychological effects, I think it's certainly kind of puts you more, it makes you connected more with yourself and depending on where you're training, it makes you kind of connected more with the environment and with nature and then there's kind of knock on effects. And I'm not that I'm to this if you, if you're going out, Ben, if you're going out this weekend, I know you don't train as long distance as I would, but if you went out for a four or five hour bike ride at the weekend, fasted and you didn't really eat much during, kind of like the reward theory mechanism is kind of kicking after and you know, even though you haven't eaten before and you run or cycle for a long time, you know, it can kind of steer you off, it can kind of make you eat either overeat or, you know, reward yourself with high carbohydrate type food or whatever. So you know, there's always kind of knock on, knock on effects to this I think particularly kind of psychological or emotional. So that would be the kind of only other kind of thing that when you really get deep into it that it starts playing around with.

Right, right, gotcha. Okay, cool. So let's talk about in terms of elite and world class athletes because you've worked with some professional people. I don't know if you can give names or if you're able to get into any details. But I guess the first part of the question I want to ask you is are there even a significant number of elite or world class athletes doing this? And if so, how are they doing it from like a practical standpoint? Like if I'm a Tour de France cyclist, am I going out with something different than like sports drink in my water bottles or what exactly is going on? How's it being used on an elite or world class level?

It's very, very difficult if you're a professional athlete of any kind, but particularly if you're a professional cyclist, it's a very difficult thing to basically do. It's a very difficult thing to start doing because for a variety of reasons. One, it's a very, it's very difficult to go against the norm when you're in a sport such as professional cycling. You know, it's got, it's got a very kind of defined way of doing things and when you're trying to, you know, flip things on its head, basically it's very hard to do that and it's very hard for it to be accepted. So professional cyclists in the professional cycling world, I know of a few, but I would rather call them more cyclical low carb, high fat kind of diets. And the fasted state stuff would obviously be done during training. You see the thing about it is, is that a lot of kind of elite world class athletes will have very, will have a lot of the adaptations that that, that's things that that low carb, high fat diets can bring or even fasted state can bring. So they will have already have like mitochondrial biogenesis, they would already have upgraded upregulated fat oxidation enzymes, they will already have intramuscular triglyceride storage in the muscles. So this is the thing where kind of makes it not only hard but sometimes they don't see the benefits of it. And like we discussed moments ago, to really see the benefits of it, it does take time even for these elite athletes for them to see marginal improvements. You're, you know, you minimum, you're talking kind of a year and for professional athlete, professional cyclists to go, okay, I'm going to go low carb, high fat for the next year and I'm going to do my, you know, my long rides fasted. It's very hard for them to take a year out to do that because it's a way, it's their living, they have, that is their work, it's their job. So that's, that's the first thing. The second thing or the second point I'll make is there's a huge amount of practical issues associated with this. If you're an elite athlete and you're traveling for training camps and you're traveling for races, there's practical aspects of, you know, if you're sitting with your team, you're on a professional cycling team and you're, you know, sitting with your team and everyone's eating, you know, cereal and breads and there's not much in, there's no coconut oil on the table and there's no, you know, avocados and organ meats and etc. Etc. You know, your, your diet has to, has to change in accordance with practicalities, unfortunately. So a lot of it comes down to simple practicalities as to why people cannot or particularly. Yeah, why elite athletes, why you know, professional athletes can't stick to this kind of regime.

Now are you aware like during though, like are people using, you know, for example, I don't know if you heard my interview with, with Dominique d' Agostino where we talked about liquid ketones and the potential for Using things like beta hydroxybutyrate and acetoacetate and ketone capsules or ketone liquids as fuel. Are there or are you aware of anyone actually doing something like that at an elite level?

Yeah, I am actually ironically say that I think I'm hopefully I'm allowed to say this, but. So keto esters, is that right? Is that what he's doing?

Yeah, like keto esters. Exactly.

Yeah, I know, I know it's gonna be using, I know it has been using professional cycling over the last year or two and it's gonna be, it's, you know, a lot of the teams are gonna start using it now.

So you've actually, you've actually seen that utilized. It's not like hearsay.

Yeah, no, they've utilized it. I don't know if you know, but there's actually a researcher in Oxford University in England, so who's been working on formulating a drink for the last few years and it's now she's basically ready to launch it. So it's, it's a keto, it's a keto ester type drink and before she, you know, before she got the rights basically to launch it, some of the, one of the professional cycling teams kind of took the stuff on board and basically has been using it for the last couple of years.

Interesting.

So that's one thing that is being used and I think it's going to become more widespread over the next couple of years.

I'm curious because I've seen you write about how today's Primal diet or Paleo diet recommendations can mislead athletes. What exactly you mean by that? For people who are exercising a lot or engaging in media social sports. What do you mean when you say that primal and Paleo recommendations could mislead them?

Yeah, I just think you're talking about two very different sets of machines. I mean, you're basically talking about an average sedentary or just an average everyday individual who's just working out to be a bit healthy versus a full time athlete. A lot of the physiological mechanisms that a full time athlete has don't need a lot of, don't need a lot of the recommendations that are, don't even need to follow a lot of the recommendations that come from today's Paleo kind of paleosphere, whatever you want to call it. I mean, to put it very simply, you're kind of comparing a Toyota Corolla with a, you know, a Ferrari. If you upgrade the engine in a Toyota Corolla, it's going to go faster. You put a new set of wheels on it or you put a new gearbox in it, it's probably going to go a lot faster. But if you, you know, you can't really upgrade the engine of a Ferrari that much or, you know, it doesn't need a new set of wheels so it doesn't get much faster. So a lot of the things that athletes need to do or don't need to do or because they're already, their physiology is different. So for instance, I mean, there's a lot of talk about say for instance, fructose being bad for the liver and causing non alcoholic fatty liver disease. And if you eat over, I don't know, 30 or 40 grams of fructose, it's going to be bad for you. I mean, I'm working with professional cyclists or could be eating 100, 150 grams of fructose a day and they've got no liver problems. So everything as you know, has to be put in context. And I think when it comes to professional or not preferred, but just full time athletes, what, you know, the way they work is just very, very different to what a obese or even a sedentary, sedentary or somebody who is insulin resistant or has any kind of, you know, illness or is not physiologically healthy. Just, you know, athletes can get very concerned when they seem to see things like, you know, don't eat fructose and when it doesn't actually affect them or even the recommendation of if you eat over 50 grams of carbohydrate, you'll lose out on, you know, ketosis. I mean, you can cycle out in and out as you know of ketosis on a daily basis. And I even think that if you're a full time athlete and you're not, yeah. If you're a full time athlete and you're pretty well adapt, fat adapted already, I think you can eat more carbohydrate and still get into ketosis. I think you can eat 100 grams, 150 grams and still be in ketosis. So it's very, I mean, it's very hard for, for the general health guru world of the paleo sphere to give specific recommendations. But there's a lot of very intelligent, convincing health gurus today. And when you read something that's posted up on the Internet, listen, listen to something you do, I mean, even I will, you know, if it sounds credible and the theory is good, I'll believe it and I'll listen to it. But what I find is a lot of These things don't really work or don't need to be done if you're. If you're already, you know, insulin left and sensitive, physiologically healthy, already kind of fat adapted, low inflammation, good sleep patterns. Like I said, you don't need to give the Ferrari that much more. Make that much more changes to it to make it go faster.

Yeah, it's interesting because that's one of the things that I've noticed is like, you'll. You'll see. I think I just saw this. It was like on Facebook or something. And like somebody had. Some girl had gone out and destroyed herself with seven miles of running and some metcon gym session and all this activity during the day. And then she rewarded herself at the end of the day with half a sweet potato. And just that whole mentality of some of these things being evil or knocking you out of ketosis or out of the benefits of fat burning or even if you're not in a state of ketosis per se, just making you feel fat because of some of these primal and paleo teachings. Yeah, I agree. Sometimes it is kind of dangerous. So I've got a few other questions that I wanted to ask you. In the time that we have left. You have kind of an opinion on the central governor effect and the way that the athletes feel during exercise. And specifically a recent study that was done on pro cycling, you mentioned to me that you wanted to. To bring up or something that you recently came across. Can you talk about that?

Sure. I mean, like I said, I mean this whole thing about being a better, becoming, you know, a better athlete, certainly related to diet, it's certainly related to training. I think fasted training is a big component of it. But, you know, I've started to realize that there's a lot of other factors that go, you know, that work or that are probably more important lifestyle factors. You know, I used to say you are what you eat. I'm kind of now say you are how you live. One of the things I've realized through working with professional athletes and just my own kind of performances is that sometimes you can do everything by the, you know, everything that you think is optimal for you. And you might have then a poor performance. And it's not because you didn't, you know, have your two spoons of coconut oil or take your beetroot juice shots or whatever it is. It's because of the state of mind that you're in and the central governor effect. And an example of that I was just trying to point out to you and I sent you a paper which was done in 2011 at the Giro d', Italia, which is the equivalent of the Tour de France here in Italy. And it was done on the liquid gas Cannondale team, I think. And, and basically what they did was they were trying to make, they were trying to assess oxidative stress and antioxidants. And so there was nine cyclists, nine riders on the team, and two doctors, I think, with them for the whole duration of the event. It's three weeks long. And what they did was they monitored their total antioxidant capacity, I think it was, and they were monitoring their oxidative stress and reactive oxygen species. And then they were treating those riders with antioxidants based on the results that they were getting. So they did a review then at the end of the Tour de Giro d' Italia on the nine individual riders. And it turns out that the two riders that had the best results during the race with the two riders with the lowest antioxidant store capacity and the highest amount of oxidative stress, and their own words in the conclusion to their paper was, sometimes it's not the physical. I think it's something, sometimes it doesn't come down to the physiology, it's down to willpower. And I think when you start really looking into something sports, you'll find that there's lots of guys and I'm, you know, I'm seeing, I know guys that, you know, top world class athlete, top worker cyclists that are, you know, living on three bowls of pasta a day. They don't know anything about ketosis, they don't know anything about, you know, the low carb, higher fat way of eating or fastest they're training. But, you know, these are the people that are winning Tour de France. So there's got to be something else going on. There are a lot of things going on and I think one of the biggest components of how you, you know, how you get more out of yourself is your mental approach to whatever it is that you're doing.

Yeah, but doesn't this stuff have an effect on health too? I mean, isn't there a difference as far as like long term health effects of eating three bowls of pasta a day versus say, engaging in more of like a higher fat or reduced meal frequency type of approach that you have?

Yeah, definitely. I mean, I'm not, I'm not, I'm not, I'm not, I'm not advocating, I'm not saying three bowls of pasta are good for you. What I'm saying is that there are People that are doing that and there are people that are, you know, winning some of the biggest sports events in the world. And you'll also, I mean, I'm living here in Italy. I know, you know, there are people here in their 80s and their 90s are still healthy, and they've been eating, you know, a cornet croissant in the morning and pasta in the evening and pizza. So sometimes, you know, there's certainly not one way of eating, I don't think. And I think there's certainly obviously a huge amount of other factors that govern.

Yeah, even like, even like genetics, like those folks you're talking about, like their parents and their grandparents and their great grandparents and their great great grandparents probably ate a similar diet too. Right. So they've got different levels of amylases and enzymes and things of that nature.

Yeah, yeah, definitely. And then, as you know, it comes into other kind of life lifestyle factors in terms of like, you know, their environment and EMFs and all those other kind of things. But I think specifically related to sports, I think, you know, I think you're going to find this over the next couple of years. I, I think we've done a lot, obviously, on physiology and supplements and, and foods for the body and for athletes. I think over the next, certainly over the next year or two, I think a lot of it's going to be down to brain hacking and how you can hack the brain and how you can improve mental focus and cognitions. So I think, I think they've already started doing some research into that in endurance athletes, actually. And I think, I think we're going to find that if, you know, if you, I think you want, if you want to win. Ironman Kona I think one of the first things or one of the most important things is, you know, your state of mind, your central governor, and how you can increase the amount of suffering you can do and all the rest of it. Would you not agree?

Yeah, exactly. I do agree. And, you know, we've just got a few minutes left, Barry, but I want to tie all this together for folks because we've gone over a ton of information. What I want to do is kind of give people an idea of if they want to combine fasting and exercise and train in a fasted state without doing damage to their bodies, how they can get started and what some of your practical recommendations are as far as how folks can do this and do it safely.

Yeah, sure. I mean, it's always important to kind of keep things practical and keep things simple, and that's the problem with these podcasts is like I'm trying to kind of summarize what I've learned in the last kind of five, 10 years. So yeah, I'll give you a very easy beginners manual, so to speak. Again, it depends on the individual and the person and what stage they're at at the moment in terms of their diet and everything else. But if they want to improve their endurance capacity and if they want to become more fat adapted, and it depends on who they are. But what I would tell them to do is to first get into doing the kind of carb backloading approach. So where they're generally eating their biggest carbohydrate meal or their only carbohydrate meal after their workout. And then it depends on the time of the workout when they are training. I would say then if you're training in the morning, I would choose one, if not two workouts, whether that be run or cycle or swim or gym, CrossFit or tennis, whatever it may be. If it's in the morning, it's always kind of important to do it when you're within one to two hours kind of of getting up. So if you get up at 7am, it's kind of good to be doing your exercise by 9am if you're starting out, because I think it's related to the cortisol levels that happen if you get up and you're not eating soon. So what I would recommend is one or two hours a week or one or two sessions a week that they start doing whatever training session that it is and choose an easier, lower volume, lower intensity type training session at the beginning. So that might be if it's somebody who's going for, I don't know, one hour easy run or two hour moderate cycle, just get up, I would say have coffee because I think coffee improves fat oxidation. I also think it improves gluconeogenesis. So in other words, the making of glucose. So get up and have a coffee and go and ride or run or whatever it is you do. And do that for a period of kind of six months, as in don't really do it anymore, maybe do it for a bit longer in terms of your. Maybe it's a longer ride or a longer run that you're doing.

That's really interesting to say that because like so many people thrust themselves into this hardcore.

Right, exactly, exactly. And that's where I think people really fail when it comes to all the recommendations that are out there. And there's so much information now online that you can get and that people just want to do it all at once. I would say, you know, the best advice I have for somebody is, you know, look at that, look at the models of training depleted and fasted state and do it, do it the easy way first. Because if you learn how to swim in the shallow end really well, when it gets into the deep ends, you'll be able to keep going and you won't sink and drown, basically. So build up boat, you know, build one or two sessions. I would say the lower carb, lower glycemic index carbs. If you are a carbohydrate eater, get onto low GI carbs and carb backload. It's very simple. Just whatever it is you're doing. If you train in the morning, have your carbs at lunch. If you train in the evening, have your carbs at dinner. And do that once or twice a week for six months. And then build it as in do a longer session or maybe do it, try it for three times a week and keep, you know, keep making, keep. You really have to go on feel and you have to listen to the body and go on what, what you think is working for you. But I will say do it in a gradual manner. So that's, you know, I would do two things. I would model your diet in order to fit with the training, in order to do the carb backloading thing or just switch the, you know, and switch to very low gi, low glycomic index carbohydrates. Don't do big volume, high intensity sessions first. To start out with do lower intensity, lower volume stuff and do that for over a few months. Then incorporate maybe something higher intensity and longer after several months and build it from there.

Gotcha. Really good advice. This is a lot of information. I know. And for folks who want the show notes, they're going to be over@BenGreenfieldFitness.com and in addition to the interview with Barry and the resources that Barry and I have talked about, I'm also going to put a link to my interview with Peter Attia, my interview with Dominique d', Agostino, my own notes on my ketogenic Ironman experiment, and my interview with Dr. Jack Cruz. And of course, if you have questions, I know Barry's great at communicating. As far as this stuff goes, I'll be there to help you out in the comments section. So if you have comments, questions, thoughts, feedback, leave them in the comments for the show notes for this episode, which are going to be over@BenGreenfieldFitness.com and we'll be sure to help you out. So, Barry, thank you so much for coming on the call today and sharing this stuff with us.

Yeah, cheers, Ben. It was good to chat. I could probably, you know, keep on talking for another few hours, but hopefully we covered the main points.

Yeah. Yeah. I think this is going to be a really good primer for folks. All right, folks. Well, this is Ben Greenfield and Barry Murray signing out from BenGreenfieldFitness.com visit BenGreenfieldFitness.com.

For even more cutting edge fitness, nutrition and performance advice.

Smoke.