Welcome & Introduction

Speaker 1

Hey y'all , and welcome back to the Find your Edge podcast . I am excited you're here . So today's episode is a special replay with Dr Matthew Stratton , a researcher and professor who is now at the University of South Alabama . His research focuses on specialty diets , particularly intermittent fasting , which is what today's episode is all about to improve health , body composition and exercise performance . He , in particular , particular explores how to optimize these diets for better adherence while maintaining their benefits . So we've taken his research and incorporated it into our longevity nutrition coaching program , with an entire module dedicated to it . Additionally , we use genetic testing to determine whether this dietary protocol aligns with your goals .

Speaker 1

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Speaker 1

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Speaker 2

No , technically .

Speaker 1

Yes , fantastic Congratulations . So he just finished his dissertation at Texas Tech and we are talking all about intermittent fasting . So , matthew , give us a little bit about yourself and your interest in this topic , and then tell us about your dissertation .

Speaker 2

Yeah . So we had kind of been dabbling around with a couple of intermittent fasting ideas and so I was like , hey , we want to take this over . And so , uh , that turned out to be still , to date , the only study that has been looking . That has looked at , uh , people trying to lose weight while lifting and how intermittent fasting affects that when especially when you're everybody's eating the same amount of food . So that way we can actually look at is intermittent fasting doing anything or is it differences in differences in food consumption , which is a big thing in a lot of the literature is they don't necessarily control for actual food consumption , they just look at fasting .

Speaker 2

And then a guy who was the on my thesis committee was a professor over at Texas Tech , and so he called me up after that and said , hey , we're starting a doc program out here at Tech . How would you want to be one of my first doc students ? And so , again , can't turn up down free grad school again . So I packed up everything from Georgia and moved out to scenic Lubbock , texas , which anyone who's been out there can tell the sarcasm in my statement right there , uh , where I just spent the last three years doing a lot of body comp supplement research .

Speaker 2

And then as well because , uh , it's my dissertation basically what we looked at was the effect of breakfast consumption on afternoon resistance training performance . So if someone eats or skips breakfast , does it actually affect their ability to perform exercise later in the day once they start eating again ? Um , and we did that in resistance training performance , um , not only because myself I'm more of a strength athlete , but also because , um , ironically , it had been somewhat done in endurance performance already . It just hadn't been done in it with lifters . So we decided to look at it with lifters . And so that was the last six months of my life , which was a fun time .

Speaker 1

Yes , yeah , for sure , okay . So let's rewind a little bit . We heard a little bit about what you're researching as it relates to intermittent fasting and lifters , but what specifically is intermittent fasting ? Cause it's one of these things . It's been around for eons , but I feel like it's definitely making a bit of a resurgence . It's kind of trendy if you would call it that right now . So , um , give us the reader's digest version of what it is .

Speaker 2

Yeah , so , like you mentioned , it's been around

Introducing Dr. Matthew Stratton and His Research

Speaker 2

pretty much as long as mankind has been around . Like you can find references to it even in the Bible there are . In pretty much every type of religion there's some version of fasting . In essence , what intermittent fasting is ? Because like not what most people think . So most people , what you talk to them about , they think about one particular protocol , which I'll mention here in a second . But intermittent fasting is actually a very broad , blanket term for a ton of different protocols that basically split everything into different periods of fasting and feeding . So you have a fasting window where , just like it sounds , you consume no calories and that's the big thing .

Speaker 2

There's no calories where depending on the type of fast you're doing , whether it's what we call a dry fast or a wet fast . So a wet fast , you can still have things like water or anything that's non-caloric . So if you still want to have , like you know , or something like that , cough , black coffee , that's no calories , that's completely fine , versus a dry fast is no food or liquid whatsoever . So , for instance , something like ramadan is typically more of a dry fast versus what most people do with . Intermittent fasting is what we consider a wet fast . So you have the fasting period and then the feeding period or feeding window , whichever you want to call it , and all the different protocols .

Speaker 2

All they do is just kind of mess with either the frequency of how often you fast or the length of the different fasts , and so the most common ones that we see , uh , most common one up until very recently in the literature was what's known as alternate day fasting , which I kind of stress my students a lot . Scientists aren't very original , so we like to name stuff after pretty much exactly what it is . So alternate day fasting is kind of exactly what it sounds like . You eat one day , don't eat the next day , and eat the next day Like eat Monday , don't eat Tuesday , eat Wednesday , don't eat Thursday , and so on and so forth . However , you know that's likely not going to be the greatest for long-term adherence . You know , if you ever like , get a client and be like hey guess what you don't get to eat at all tomorrow .

Speaker 2

Uh , might be able to do that a couple of times , but , you know , after a while . So they came up with this thing called modified alternate day fasting , where you find the exact same thing except you have a really small meal on um , those fasting days around lunchtime . Typically it's about three to 500 calories . So , a little bit they found a little bit better adherence , but up until , uh , the late 2010, . So , like 2017 inch , that was the predominant one that we saw in the literature .

Speaker 2

There's another one we don't see in the literature quite as much , but I see it pretty frequently in the field . We term periodic fasting , which that's where , again , like I say , where someone is fasting periodically . You're not fasting every , you're not fasting every day , you're not fasting every other day , you're just doing it every so often . So the most common versions of that we see are things like colloquial term for the eat stop . Eat is a really common one , also known as whole day fasting , where someone might do one 24 hour fast . Nice thing about that was , you know , despite you know being 24 hours , and I think is , you can still eat every single day Because if you think about it . You know , let's say you start fasting at 6pm one day and then you fast till 6pm the next day . You can still , you know , eat kind of breakfast , lunch and like really early dinner or something like that on one day and then eat dinner the next day , and so you're still being able to eat every single day , which is nice .

Speaker 2

And then the most common one that most people associate with intermittent fasting is this one called time-restricted eating . This is what we call it in literature , or TRE , if you look at all the older literature so it's kind of funny to say , but older literature around like 2016 . So if you go back , then it's time restricted feeding . Now , more commonly , we call it time restricted eating . But if you ever see the TRF versus TRE , it's the exact same thing .

Speaker 2

And with that it's kind of mostly referring to is again what most people think about for intermittent fasting . So that's those daily , short , shorter term fasts . So , like , the most common protocol you'll see is the 16 and 8 protocol , which is fast for 16 hours and then put all your food in an eight hour window , which for most people sounds like a lot , but if we break it down , so that's eating between noon and 8 pm for most people . Now , keep in mind , you can move that window wherever you want in the day . It doesn't have to be noon to 8 pm , it's just the most common one you see in practice is noon to 8 pm . And what I thought . You know I deal with a lot of college students and stuff , so I say , like you know , initially mentioned .

Speaker 1

Like I don't think I can do that like , well , if you think about , okay .

Speaker 2

So people like to sleep until the very last second before you have to round up to class and so wake up the alarm got to be out of the house two seconds later then likely go to class , go to work , whatever , it's been a little while . Next , maybe didn't really eat that much or at all , because you just haven't had time to , like , sit down and next thing you know you're not eating until lunch and guess what , you have a dinner a little bit earlier and you're intermittent fasting . Yay , um , so it's . It's pretty close to actually what a lot of people do kind of inadvertently , um , did there .

Speaker 2

We do have some more extreme examples of it , like the what's sometimes known as the warrior diet uh , is the 20 and four , so so it's the same thing fasting for 20 , putting all your meals um , in a four hour window . And then there are some um more kind of niche variants that are starting to show up . So I have one called like early TRE now , which is some people are kind of pushing for a lot of the work , for that is coming out of Courtney Peterson's lab , who does a lot of really good work , especially in clinical populations , and I believe she's still at University of Alabama , birmingham and they and that's basically doing the same thing , just kind of moving that window to earlier in the day .

Speaker 1

And you mentioned clinical population , right . So is she working with , like , diabetics or heart disease or something along those lines ? Yeah , you're working with athletes , right ?

Speaker 2

Yeah , so I deal mostly with , um , healthily athletic populations . Uh , because anytime of literature like this , typically the population we don't see it in as much as in healthy athletic populations . Uh , because anytime of literature like this , typically the population we don't see it in as much as in healthy athletic populations . Um , but yeah , doing like the mate , uh , one of the key early TRF studies , it was in pre-diabetics . So that's the sudden 2018 paper , which was in pre-diabetics , which we'd like to talk about a lot .

Speaker 1

Um , so cool this is . This is great to get like the very specific information , Cause I originally found you from doing a presentation for the international society of sports nutrition , um , on this topic , and it was great to see all the literature laid out and then you had this great picture of all the different books that are out on it . Ooh , let me try this diet . But it sounds like there's a lot of different ways of doing this , and some of them are well-researched and some of them perhaps not too much .

Speaker 2

Yeah , and and especially depending on the population that you're trying to talk about , I would say a lot of it is not , not as much as we would like to think , because it didn't really start getting popular until only a couple of years ago . Yeah , and so , in terms of you know , studies that combine it with exercise , right now , I think we're only at about six or seven studies .

Speaker 1

Okay , yeah , so let's . I'm so excited to hear about your research , so you decided to work with strength athletes , just cause you know it sounds like that's a little bit more of an interest for you . So how'd you start ? What were your ? What were some of your methods ?

Speaker 2

Uh , the first kind of big one which was my thesis , that was one where we got it was about 32 people and then put them . So that was the first thing which we were able to actually like control for diet . And so we put them through a four week training protocol where they came in and for supervised training three times per week .

Speaker 1

We had these men and women . So this study was just men .

Speaker 2

Okay , the most recent study we did was males and females . Okay , the reason we actually did it with men was because it had somewhat already actually been done with females . Interesting , it's one of the few times that you can say like , oh yeah , the reason we did guys is because we can already kind of point to one that's somewhat similar in females . So now we want to do it males , and when , typically 90% of the time , it's the opposite , yep . And so we got 32 college age dudes come in supervised training three times per week so watch them do every single rep of every single set .

Speaker 2

I got really good at counting to eight and then basically looked at changes in body composition , so how much muscle mass they grow , how much fat mass did they lose , all that kind of stuff using and this was also the first study to use what we would say the research standard , so a four compartment model , previously just used dexa , which there's nothing wrong with dexa if you're going to use one device . It's still a very , very good device , but it's not the research gold standard as well as look at changes and things like resting metabolic rate and all that kind of stuff . And so we tested their resting metabolic

Understanding Intermittent Fasting: Methods and Protocols

Speaker 2

rate and then put them on a diet in which we wanted them to be about in the 25 estimated calorie deficit to try to get them to lose weight , which ?

Speaker 2

was also one of the big things about this one because all the previous ones , the goal wasn't really to actually get people to lose weight . So that's a big thing . When trying to like interpret a lot of this literature is think about what is the actual , what was it trying to achieve ? So , for instance , the very first study that did this , which was what I think kind of got it really popular , which was the Morrow 2016 paper .

Speaker 2

They because people looked at it and said like oh , this kind of semi-controlled diet , you know , and people who were doing the 16 and eight protocol lost , much lost . Oh , this kind of semi-controlled diet , you know . People who were doing the 16 and eight protocol lost weight but kind of maintained performance over these eight weeks versus the other group , didn't . Well , in that study , their goal was actually to try to get them to maintain weight and so that's why they had a really high calorie intake . If you look at it , they were eating . They were told to eat about 3000 calories per day , which is a really big thing with a bunch of these studies is look at the actual how much calories are being asked to eat .

Speaker 2

Because the dirty little secret about intermittent fasting is typically how it works is we're just tricking people and eating less , and so there's been a couple , there's been a fair bit of studies that show when you put people on these protocols , it's harder to eat more , because now you're putting it into a shorter time window , so people are fuller for longer , so they're going to , they're going to eat less , and so throughout all of these studies , you know , we kind of see that typically the intermittent fasting group was the one that was generally eating less , whether they wanted to or not , and sometimes that didn't result in what we call in research a statistically significant difference . So for those of you that those of your listeners that aren't familiar with that , basically sometimes if you look at numbers you might see there's a difference right there . But if the difference isn't large enough for us to say it's like a significant enough difference for us to say in science that it's likely that's the thing that's causing it or that's a real difference .

Speaker 1

So sometimes that's why we say that like yeah , if you look at those two numbers , those two numbers are different , but we won't say it's a statistically significant difference . But one of the things that was my least favorite class in grad school , by the way was statistics .

Speaker 2

It's a lot of people's least favorite . I don't think you need to learn all the intricacies of like ANOVAs and t-tests and linear mixed models and all that kind of stuff . But learning some of the basics about interpretation and stuff like that I think can be really important for people so they can understand differences like statistically significant and all that kind of stuff . But I think we run into a thing of statistical significance versus practical significance . The difference might be so small on daily intake that it was not statistically significant .

Speaker 2

But that daily intake when it's compounded over , you know , eight , four , eight , 12 weeks , whatever the length of the study is , results in a meaningful difference which you know for some of these studies there might not have been a practically significant difference in calorie intake , but there was just enough that at the end of those eight weeks it was actually what caused some of the body composition changes , and so that's what we were seeing in previous research . So for our study , that's why we actually were the first to kind of control for that across the board . So everyone ate around 1900 calories , 1.8 grams per kg of protein , making sure that they're eating a good amount of protein , along with the supervised training . And so we found , when diet was controlled , we actually didn't find a difference in strength performance or body composition changes . For my dissertation , we kind of did something similar , except more in the acute setting , and so because the most common meal that is skipped with intermittent fasting is breakfast , we wanted to look at , you know , specifically how does breakfast ? You know , once people start eating again , does that potentially impact the session later in the day ? And there's been a little bit of .

Speaker 2

There were three studies in that . Two of them were in cyclists and then one of them was in rowing performance . So again , none of them were in lifters . That's one of the reasons , you know , we decided to look at that population as well . Also , all of those have been in habitual breakfast consumers , and so people who are typically consuming breakfast not people who are typically skipping breakfast or fasting , practicing fasting , something like that and that's important because we found , through a couple studies , that there's a large psychological component to it , and this one was done actually in both cyclists and lifters . So , if you want to like , look up the actual papers the cyclist paper is the MIRS 2018 paper and then the lifting paper is going to be the Naha Rudin 2020 paper but what they actually showed was when they gave people so in the initial studies they basically had them come in , gave them water or carbohydrate breakfast and then had them exercise . They found they did that . There was a difference in performance , you know . But then if they gave them water versus a placebo versus a carbohydrate breakfast , there was a difference between water and the placebo and carbohydrate , but no difference between placebo and carbohydrate . So that's showing that pretty much all of the performance decrements that were shown previous were likely psychological the person coming in thinking like , okay , I need this type and I need to be eating and doing all this , and since I didn't , I'm going to perform less . And so self-fulfilling prophecy if you believe you're going to perform less you perform , you perform worse . So we decided to kind of try to control for that , to look at people who habitually follow these kinds of patterns as well .

Speaker 2

Another kind of big aspect of those studies is they all used what we call time trials . So basically and that's a best way to kind of mimic a race , because that's how , because that's uh how fast you know , an individual might be able to go from point A to point B , but uh , that's not necessarily very representative of how someone's likely going to train and especially if you're dealing with athletes , most of the time I feel like they're not going to forget to eat on race day . So if they're going to forget to eat breakfast , it's likely going to be on a busy training day . Or looking at you know how , if you want to do carbohydrate periodization , you know if they want to do some some various training sessions , fasted or something like that , but those ones aren't going to be , you know , all out time trials . Those are going to be your lighter sessions .

Speaker 2

So that's why , for us , we tried to do something that actually mimicked more of a typical training session , instead of the what you commonly see in literature of time trials or time to exhaustion , which is basically where we put someone at a certain intensity and just see how long they can go . Again , very interesting and very good for finding differences , but not very well representative of how people might actually train and so how these dietary protocols might affect training . And then when we did that you know we're still looking at all the aspects of it , but we again males and females , and these were pretty strong individuals , so they had to be able to meet various strength criteria to get into the study and this one . We also gave them all the food that we wanted them to eat .

Speaker 1

Wow , that signed me up .

Speaker 2

Yeah that was a good lot If , if you liked Uncrustables , you know so it really is real food yeah .

Speaker 2

And so , um , yeah , so for this one we provided all food and basically people ate the same exact amount of food . It was just either a breakfast and lunch and then come in and train in the afternoon , or skip breakfast and eat the same amount of food at lunch and then come in and train , and so we were able to control that , um , a lot more than previous studies , and in that one we didn't find any difference , but it was likely because of more of that submaximal nature . So we were doing something that's going to be more well representative of an actual training session . Now , that's not necessarily to say that , you know , know , it's never going to affect anything because , like we mentioned with the diet before , those small changes in that might not quite be detectable at with our current statistical methods .

Speaker 2

In one session , if it's compounded , session over session over session over session , might make a difference . So to truly see an , you'd have to do some of these longer term training studies , and the longest training study that we have to date is eight weeks with intermittent fasting , and so even then that , if you're looking at things like building muscle for hypertrophy and stuff like that , that's typically like the shortest amount of time you'd be able to see anything like six to eight weeks . Shortest amount of time you'd be able to see anything like six to eight weeks . And for improvements and things like vo2 max and all that and so for endurance athletes you know , it could be even longer sometime , depending on the training status of the individual .

Speaker 2

So that's not necessarily saying that , um , in fact , like skipping breakfast isn't going to impair it , but it's not going to directly is going to impair it either .

Speaker 2

So the way that I kind of sum up all the studies that I've done is you do you , you know it's you . If you like , if this type of eating fits your style and fits your lifestyle and you enjoy doing it and fits your lifestyle and you enjoy doing it , um , then it shows that you can still do it , as long as you're making sure you're still eating the same amount of calories , protein , carbs , fats , that type of thing that we'd recommend . You can still do it and be successful . It's in . But don't feel like you're going to get an extra advantage by doing this , cause so far the literature doesn't show that you get an extra fat loss advantage or anything like , or performance increase or anything like that when um diet is equated for I think this also goes to show that you have to stick with it , whether you're doing something for eight weeks or 16 weeks or a year , or we can't just like , snap our fingers and magically , ha ha , we're thinner .

Speaker 1

I mean , I'd be a trillionaire by now . I can't be really snap our fingers and magically , ha ha , we're thinner . I mean , I'd be a trillionaire by now . It'd be really nice .

Speaker 2

Right , it'd be really nice .

Speaker 2

But yeah , that's one of the biggest things and that's one of the reasons I kind of actually like IF a lot is because I think out of all , because we know pretty much all specialty diets out there work the same way by just by tricking you into eating less , and so with with if you know it's , there's a couple reviews out there to suggest on average , when you tell people to eat this way , it gets people to inadvertently cut their calories by about 20 , but it's a pretty good deficit .

Speaker 2

And because people will typically eat more when they first that first meal , when they start eating again but this is not enough to make up all the calories that they would have missed , like at breakfast , and then , um , they kind of go back to normal eating patterns later in the day and so they still end up eating less overall . And the thing that I kind of like about intermittent fasting is because , like , uh , all it says is about when to eat , not what to eat , but there's nothing that says that um , meal window , the feeding window , has to be the exact same time every single day .

Speaker 2

So you know , let's say you want to do , you know , 16 , 16 and eight , whatever . And then , monday through Friday , you know you're at work most of the day and so you want to put yours at , like you know , noon to 8pm , because that still allows you , you can have lunch at work and then come home , have dinner with your family , still have good , you know , nutrition guidelines around training , all that kind of stuff . And then , but you know , on Saturday comes up and you've got to go to a birthday party for your kids or something like that , that you know there's going to be food there .

Speaker 1

Well , you can still keep that eight hour window .

Speaker 2

You just shift it up a little bit and then . So now you can still have kind of that normal social life and you can just kind of move that window around a little bit .

Speaker 1

I think that is interesting that you mentioned that . Just because so many I mean we'll call this a diet , right ? So many diets are seemingly restrictive in some way and people can't really figure out the logistics of how to do something like this , right ? So that's interesting that you sort of explained it that way . Like you know , you can be kind of flexible and also you do you Right , so . But it sounds to me like the main overarching theme is you're getting fewer calories . Like you said , you're sort of tricking yourself into , in essence , getting fewer calories and if you stick with it long enough and you enjoy it great , you're probably going to get results . Is that kind of what I'm hearing ?

Speaker 2

Yeah . And so , like we , we know the number one factor to long-term success is just adherence , and so it's finding something that allows people , allows you to stick to it , that you enjoy doing it . So it's . You know , if you don't like fasting , it's fine . There are a billion other routes that you can go .

Speaker 2

That's why I know a lot of people when I present kind of some of the literature showing like , oh yeah , here's the stuff showing that when you control for this it doesn't really make a difference , they go , oh , that kind of sucks . Knowing that when you control for this it doesn't really make a difference , they go , oh , that kind of sucks . And the way I look at it is actually I actually look at it as a very good thing , because that means no one's being kind of pigeonholed or forced to do one thing in order to kind of reach the goal that they're looking for . You have a bunch of different options , and this just shows that intermittent fasting is an option . It's just not your only option . So if intermittent fasting isn't for you , you can try one of the other , like 12 million paths out there , if you like intermittent fasting . It shows you can still do intermittent fasting and be successful .

Speaker 1

So that begs the question , to me at least , of what were some of the things that people enjoyed about it from your subjects , and what were some of the common complaints .

Speaker 2

Yeah , so the common things that some people like about it . And this is why I'd say , typically I would only recommend someone do this when they're trying to lose weight . Um , I get that question occasionally . I would never , you know , recommend something like this If someone's trying to put on weight . On weight because you're doing something that is making it harder to eat more and which is kind of going against the goal of what you need to do to put on weight . But one of the benefits of it is , if you are trying to lose weight because you're able to have those meals closer together ,

The Psychological Effects of Fasting and Adherence Strategies

Speaker 2

typically you feel a little bit fuller during that eating window .

Speaker 2

Now one thing to keep in mind when people start doing this , it's very common that you will feel very hungry , you know , for the first couple of weeks throughout that fasting window , but that will typically go away like after like a week or two . People kind of adapt to that a bit .

Speaker 2

But yeah , the big thing is because you're putting all that same normal food that same food fills you up a little bit more because it's in a shorter time period , like if you have to . If you have to wait from eight o'clock to noon and then you know noon to like seven to eat , you're gonna be a lot hungrier in that intermediate time period versus if you're having those same meals at noon three and you know seven or something like that . Some of the complaints that I would see occasionally uh were people that had you know jobs where they bring in like bagels at work or something like that . It would be having to remember it's like I can't really go over there and have that the breakfast at the office supplied or something like that , because it's during my fasting window .

Speaker 1

So it sounds like more psychological challenges .

Speaker 2

Yeah . So all of the complaints , typically I find more the psychological aspect of it . All of the complaints , typically I find more the psychological aspect of it , and so that's where I say it's , you know , finding one that kind of like fits for you . So if you know that's an issue and you still want to do it , maybe moving your fasting window to something like 10 to 6 or something , so you have an early dinner , but it's since's you start eating a little bit earlier . They uh , you're able to still have like a late breakfast that some people at the office might not look at you funny for eating .

Speaker 1

Yeah , okay , so this is . This is super helpful . Uh , quick question about your research methods . So you had you're watching these people work out , so they had breakfast . Then when was their workout ? In relation to their feeding times ?

Speaker 2

So that's that's a good point . Um , pretty much all of the studies to date in terms of specifically looking at intermittent fasting , the exercise has been done within the feeding window , and that's what I would still kind of recommend is to try to exercise within the feeding window . Um , and depending on the type of workout you're doing , it'll impact it a bit more . But in general , just so that we can , you know , make sure you're following good peri-workout nutrition guidelines , exercising within the feeding window is going to allow you to do that the best . Now , if the only time that you can fit it into your day is in the fasting window , that's fine . Just likely it's going to affect it less if the workout lasts less than an hour , and if the workout lasts more than an hour , it'll affect it a lot more . There's a really interesting meta-analysis by Aird and colleagues that came out in 2018 , kind of looking at that , given that meta-analysis was only looking at aerobic training and found that working out fasted really was only impacted if it was over an hour .

Speaker 1

In other words , their time to exhaustion was longer or yeah .

Speaker 2

So it was things like yeah , time to exhaust , they weren't able to go as long .

Speaker 1

Or like RPE was higher .

Speaker 2

perhaps RPE is typically higher , so that's another thing , just generally working out FACET in general , typically RPE will be a little bit higher . So when most people work out FACET , if they're on an RPE based program they'll self-select a little bit lower intensity or slower speed because RPE will be artificially increased a little bit .

Speaker 1

For those of you guys who don't know what RPE is , rating of perceived exertion AKA how hard are you , how hard do you feel like you're going ?

Speaker 2

Right , yeah , so if you know someone tells you to go out for a run at like a six out of 10 or something like that , you know that , um , six might feel a little bit higher if you were doing it fasted than if you've done it after breakfast . But again , those most that stuff again is acute . So if you're doing it consistently it's likely that that you get kind of like adapted to that and that wouldn't be as big of a deal . Yeah , um , there's actually some versions of diet out there called under what we call carbohydrate periodization . That kind of actually will promote that . So you do your recovery sessions kind of fasted . But that's a big aspect of that is the fasted sessions that you're doing are your low intensity sessions to follow that , because I see that come up a lot with fasted training .

Speaker 1

People like oh , look at look at this literature .

Speaker 2

Yes , just remember that in that literature what they're doing the fasted training is all the low intensity recovery sessions , the actual like heavy , like tempo work , speed work , heavy intervals , all that stuff is still done in normal , like fed conditions .

Speaker 1

Good point . I'm glad that you brought that up , cause I think so many people , especially in our endurance world , you know oh , we're going to burn more fat , so we have to do all our workouts fasted , and I encourage people to not do that Just like you recommended , because similarly , do you want to not feel great for your workouts . I feel like part of working out is to feel more confident and feel stronger and feel good about what you're doing , rather than the opposite .

Speaker 2

Yeah and we have tons of literature back that up that people find the exercise more enjoyable .

Speaker 2

They're more likely to do it more , and so you want to do whatever you can dietary wise to make that session feel more impactful , more enjoyable , all that kind of stuff and um , but that's that's the biggest one that I run into people talking about , like fasted training and carbohydrate pre-position , and the reason it potentially burns a little bit more fat is because it's at a lower intensity and so the lower intensity it burns more fat .

Speaker 2

Remember , just because it burns more fat doesn't necessarily burns more calories and so the higher . What we see with that type of exercise all the time , especially fasted cardio and stuff like that , is , yes , the calories you burn might slightly be a higher percentage of fat than carbohydrate . However , you burn so many calories less overall because the intensity is a lot lower , that if you're doing that higher intensity work , even though it's a lower percentage fat , it's still overall a ton more calories and overall still more fat , even though it's at a lower percentage . So doing what you can to still maximize performance within that training session is , regardless of the macronutrient that's being burned , for it is going to result in the better body composition outcomes .

Speaker 1

Good point , love that . So I always like to finish each episode with two or three takeaways that our listeners can absorb , as it relates to diet , fasting , exercise . So let's hear them .

Speaker 2

So the biggest takeaway I would always say is , again , the most unscientific way I can sum up intermittent fasting is you , do you . So if it works for you and it's something you like doing , the literature shows you can still be successful doing it , provided that you're making sure you're still getting the calorie intake that you want protein intake and carbohydrate intake . So endurance athletes really make sure to focus on protein and carbohydrate intake , because most people will eat less protein inadvertently when they start intermittent fasting . So start those meals off , making sure you're getting the right amount of protein , and then build everything else out around that . So if you like doing it , it's completely . It's completely fine , it's good .

Speaker 2

Go ahead and do it If it works for your lifestyle . Just keep that caveat in mind . Ideally , I would still say try to put the training session within the feeding window , but if you can't and it has to be , you know , just because the only time because you've got family and kids and work and whatever the only time you can get it in is , you know , right , when you get up in the morning , that's fine . If you're gonna do it fasted , just understand that , especially initially , it might feel like you're having to work a little bit harder for those workouts .

Speaker 2

But if you don't like doing it and you try it and you feel like no , this just isn't for me that's okay . Don't feel like you have to because it's going to make you lose more fat or make you a lot stronger run or increase your endurance crazy amounts Cause so far the literature just doesn't doesn't show that . So just make sure that you're eating how you should . You can just don't feel like you have to .

Speaker 1

That's great , awesome . Well , dr Stratton , thank you so much for joining us . Um , good luck in all of your endeavors and thanks for educating us . Thanks , I hope you enjoyed our episode today on intermittent fasting and , once again , if you're ready to equip yourself with the tools for sustainable , healthy nutrition tailored to your unique genetics and mindset , we'd love to have you join us again . This offer ends February 28th . Using the code genetics2025 for $200 off to get started today , head to theenduranceedgecom forward , slash longevity and I cannot wait to see you there . Thanks again for listening .