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Meghann Featherstun is a Nutritionist and experienced Sports Dietician with particular knowledge around fasting in endurance athletes. In this episode, Meghann talks about her recommendations for exercising in a fasted state including the fasting window and the exercise intensities. Meghann also comments on the differences females have compared to males when fasting and the impact it has on hormone function. Lastly, Meghann answers a list of patron questions: Is there an optimal fasting window when exercising and strength training in the morning? What does Meghann think about Dr. Sims' take on no fasting for female athletes? Does fasting affect injury recovery? Click here for Meghann's website, Instagram and podcast 'fuel for the sole' Become a patron! Receive Run Smarter Emails Book a FREE Injury chat with Brodie Run Smarter App IOS or Android Podcast Facebook group Run Smarter Course with code 'PODCAST' for 3-day free trial.
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On today's episode, How Safe is Fasting for Runners with Megan Featherston. Welcome to the Run Smarter podcast, the podcast helping you overcome your current and future running injuries by educating and transforming you into a healthier, stronger, smarter runner. If you're like me, running is life. But more often than not, injuries disrupt this lifestyle. And once you are injured, you're looking for answers and met with bad advice and conflicting messages circulating the running community. The world shouldn't be like this. You deserve to run injury free and have access to the right information. That's why I've made it my mission, to bring clarity and control to every runner. My name is Brodie Sharp, I am a physiotherapist, a former chronic injury sufferer, and your podcast host. I am excited that you have found this podcast and by default, become the Run Smarter Scholar. So let's work together to overcome your injury, restore your confidence, and start spreading the right information back into your running community. So let's begin today's lesson. First of all, at the top of the show, I want to say a big thanks to Erin Platy, who came up with this suggestion to have Megan on the podcast and talk about fasting. And it was a great episode, great conversation. And I discussed it a little bit during the actual chat. But I feel like with this particular topic, it's good to get a whole bunch of different perspectives, a whole bunch of different opinions from well-respected experts, because there are some differing opinions amongst even the elites and the well-versed with the evidence-based advice. And so Megan is a sports dietitian. I've been a sports dietitian for, I think she said, over 10 years. And I've had to listen to her on other podcasts and is just very well-versed, very knowledgeable on this topic and has a slightly different take to people I've had on the past. And so it's worth getting her on to voice her professional take on this particular topic and it was a fascinating conversation. We delve into like the nuances between males and females when it comes to fasting and different running goals and different running conditions, intensities when it comes to this advice around fasting. And so you guys are going to love it. I know these particular topics around diet, nutrition, fasting has been very popular in the past and so no doubt this will be one of those as well. Thanks to all the patrons who submitted their questions. It really added to the quality of information throughout this episode. So thank you very much for that. And if you are interested in what Megan has to say and want to know more information, all the links will be in the show notes. Megan, welcome to the podcast. Thanks for joining me today. Thanks for having me, Brody. It is my pleasure. I, this is a, a topic that I, I usually don't do topics like a repeat of a topic too often. Usually if I cover shin splints, then that's sort of where I leave it. But I think for this particular topic around fasting and around diet, there's so many different takes, so many different opinions, so much wisdom out there that I think it requires several different people just to get their separate takes and see if there's any common agreement in any certain areas or whether there's, you know, a lot of grey areas. And so I've already done an episode around fasting. And is it okay to exercise and run with fasting with Kira Sutherland and Kira Sutherland, I'll say that again, on episode 140. And I wouldn't mind probably getting a bit of a take on your opinion on what Kira said as well amongst your own guidance. But before we get dive into that, can you maybe just introduce yourself and I guess your qualifications, but also your running history and your history around like nutrition and those sorts of things. Absolutely. So my name is Megan Featherston and it's very confusing because I named my business Featherstone Nutrition. So people get a little hung up on that Featherston, Featherstone, but you know, neither here nor there are answer to both. And I have been a dietician for, gosh, 15 years now. think, don't quote me on that. But I've been a sports dietician for the past 10 years. And so, you know, I think both of my former nutrition life and my current nutrition life lend, you know, interesting different opinions and thoughts and research on this topic today, because I do think athletic populations versus, you know, people with chronic diseases, it kind of differentiates a little bit there. So talk about that. But I have owned my own business for sports nutrition for the past four years. And that's my baby, that's my passion now. So I work with endurance athletes, primarily runners, but also some triathletes all over the world and all over the United States as well. All different ability levels from the Olympic level down to the weekend warriors and have just built a phenomenal business around that. So that's kind of where I'm at now. And I think we all kind of follow our own passions based on what we like to do, right? So I got into running. Kind of as a dare, truthfully. I had a friend at the time that was running a marathon and he was like, hey, come train with me. And I was like, oh, okay. And I knew some people that did it and I was like, oh, I could probably do this. So my first road race ever was a marathon. So I pinned a bib to my shirt and went out there and had no idea what I was getting into. I did train for it, but again, went from zero to marathon from a running background and just fell in love with it. Fell in love with the grind of it, the training, the experience of it. all walks of life that are involved with running and that if anybody wants to do it, they can do it. So my first marathon was a 357 high and my last marathon was a 257 low. So took over an hour off my marathon from when I started to this past fall. So, you know, I think I can truly relate to, you know, all ability levels when it comes to that. And then just absolutely love, you know, what I do with that. Oh, congratulations. That's a tremendous. Tremendous time, a tremendous improvement compared to your first marathon. That's insane. And did you have like training yourself doing your own marathon training and performing in the marathon? Did you have any, um, well, were you studying as a nutritionist at the time? Or did you, um, you know, how, how did you respond with your own nutritional strategies? Absolutely. So I studied sports nutrition in grad school. Um, had a phenomenal teacher. So when I ran my first marathon, I was already a dietician, and I was working in a neuro intensive care unit. So I was feeding people through tubes and IVs. So very different from what I'm doing now, but always had kind of this side passion of sports nutrition. So when I first started training for my marathon, I did everything wrong, you know? And I think sometimes we're our own best skinny pigs. I mean, I would carry only water. I'm a super salty sweater. We know how that ends. I think I took. one and a half gels in my first marathon, you know, like, yes, I had the knowledge, but I hadn't actually applied it or figured it out. Or so then after that, I was like, oh my gosh, very research heavy, very big nerd when it comes to that and just dove into it. Like, all right, like what is right here? What does this look like? And then I played around with my own training and just kind of continue to immerse myself in it. I made the same mistake for my first marathon. I had I think I have a low sweat rate and I trained for a half marathon a couple of months prior to that and just didn't drink at all and was fine. And then come the full marathon, it was a hot warmer day and I'm like, okay, let me pay attention and actually start drinking some water. I didn't know how to drink water while running. I took gels in my bag, which was just a part of my race kit and I never had gels before in my life and just put it in my pockets and started eating them for the... the very first time during the race and struggled with those, threw them out and then like that. So I'm with you in the same sense that my first marathon just did everything wrong, essentially. Exactly. So when I have people coming to me and they're like, I'm running my first marathon. I'm like, you are leaps and bounds beyond where most people are for as far as how they're getting prepared for their first marathon. I get so excited, but yeah, I think. So we've had, I'm happy just to dive straight into the content. Cause usually when we're talking about fasting or We're introducing a new concept. I like to say like, what is fasting? What are different types of fasting? All those sorts of things, like a bit of a warmup questions, but because I've done it before, I'm happy just to dive straight in. Do you see, I guess we'll start with what are the benefits of fasting under what circumstances, where does your opinion lie in the athletic population? So in the athletic population, I never recommend intermittent fasting or any type of fasting for my athletes. Do I have some athletes that come to me and they're doing it? and are questioning whether it's right, and we have a discussion about what is right for them, or do I have athletes come to me that are like, I'm doing this, help me do it in the healthiest way, right? So I think it's kind of all three of those things. Like, I'm never gonna recommend it if somebody isn't doing it, but if somebody is, and that's something that they feel very strongly about, I'm gonna do everything I can to make sure that we're doing this in the best way possible so that their performance and their overall health don't suffer from that type of thing, because I think it's a very different take on fasting if it's in an athletic population versus someone who is not, right? So I think that's just a big differentiation. So I guess in everyday life, are there any circumstances where you would recommend intermittent fasting? So they've done some really phenomenal research on people with like type two diabetes, um, and actually giving our body a break from feeding it and digesting it and the response of insulin when we eat. And there is some really phenomenal research, especially in men with type two diabetes that we can, if we're shortening that eating window throughout the day, that we can really lower that hemoglobin A1C. So. there are some specific disease states and populations that perhaps if this works for them, it might not be a terrible idea. They have done a ton of research on weight loss, right? And intermittent fasting, I think that's why a lot of people grab onto it. But when you truly look at some of the best studies that they've done on it and they put it head to head with like a calorie controlled diet versus different types of intermittent fasting, they come out pretty much head to head. Like they both work. Right? So I think that's a good message for people like that aren't athletes that are trying to lose weight and they're thinking about intermittent fasting. It's an option. Is it a superior option? I don't think so from the research that I've scoured, but is it an option that works for some people better than calorie counting? Right? Because I mean intermittent fasting is literally like a light switch. You're on or off. You're eating or you're not right? Whereas a calorie controlled diet is more like a dimmer switch. Like we're just kind of turning things down for a little while and some people's minds click. a little bit better with one versus the other. So I think it's just interesting to know. You often hear people that are intermittent fasting or bust, but I think just like most things in life, some things work for some people and some other things work for other people better. Yeah, especially if you have the control or the strategy. If you wanted to do the calorie restriction, you need to be very disciplined. window, if you have like a window of I'm not eating, this is what's set out for me, then mentally, it's easier to you're not like struggling with yourself, or like should I have this? Should I have that? And that actual struggle and the gray zone can provide a lot of confusion, but then also increase the likelihood of someone going awry of that, especially if they're not that disciplined. Right. Because I think we just have too many eating hours of the day. You know, I'm sure it's probably the same where you're at. Like you can get food 24 seven, you know, there is some place that you can get access to food and it's very normal in our culture to just be eating all day. So to your point, like if that window is shortened and there's just not an option, you're not even thinking like, can I have that? You're just like, no, I'm not eating right now. I think, you know, there could be some benefit to that for a lot of people. Yeah. We kind of just glossed over your opinions on exercise and fasting and runners shouldn't be fasting. In the research that you've gone through, why have you come to that conclusion that runners shouldn't be intermittent fasting? So I think my kind of hard stop is we shouldn't be working out in a fasting window. So that's kind of where I'm at, right? Like if we're working out somewhere, we need to make sure that our eating window is surrounding that workout. And the main reasons for that is both the pre-run nutrition and even more so that recovery nutrition afterwards. So there's just so much phenomenal research out there that especially endurance runners that are running for over an hour most days of the week and turning around back to back to back, maybe they have a long run, they have a workout, there really is a lot of value to maximizing those recovery windows, which we have a few of them. Right? Like a lot of people, you have to eat within an hour. And it's like, yeah, that's probably the best. Right. But, you know, we have a couple more windows we can work throughout the day. But when someone is intently training and really trying to push their fitness to the next level, trying to optimize their body composition, if we are continually missing that recovery window, because let's say we're intermittent fasting and we're eating from noon to eight and we work out at six in the morning. So it's three or four hours post workout before we're eating our first meal. what we're happening is we're just in a completely catabolic state for those three or four hours. So we're breaking down that muscle mass that is trying desperately to rebuild itself and it just doesn't have the tools to rebuild it because we haven't eaten for 16 hours. So I just think it's a huge detriment to people's performance and then also recovery. So we're not going to gain as much in those workouts and then we're not going to recover as much. We're not going to bounce back as quickly. So you know, I just have not seen anything. to kind of go against my gut instinct from the research that I've read as far as, you know, that's kind of like my hard and fast rule. Like if we're fasting, it's, we're not working out in that fasting window. Um, if, if our goal is performance and right, like if our goal is performance, we need to make sure we're supporting that. Yeah. I wrote down a couple of follow-ups there, but there's a, I guess there's a lot of, um, specifics that that's worth discussing. So you're talking about your apprehensions around intermittent fasting because during exercise and when you are challenging your body, the body wants fuel, it wants nutrition at once. Like, um, once that to not only to perform, but also to recover afterwards. And if you're restricting your body of that, then it's only of detriment. Um, how about if someone were too fast on their non-running days and if someone's not, you know, running. five, six times a week, if they're just a recreational runner running three times a week. Is there any benefit to them, intermittent fasting on their non-running days when the body isn't starving for those nutrients? I mean, that would be like a middle ground that I think could be a compromise, right? Like if I'm pretending what you're saying as a client that I'm working with, you know, I think if they really do want to do intermittent fasting a few days, whether it's just easy for them to turn their mind off and only eat during certain hours or they like how they feel, right? I hear that sometimes too. Like I like how I feel if I don't eat until noon. And if that's something, it certainly would be safer to be doing it on those off days, you know, especially like you're saying, if they're not training for a specific race, they're just a recreational runner running three days a week. You know, to me, that's a very different scenario in there. And what I do typically is just kind of teach people like what would be some red flags or some things that might start to pop up that would make us think like, is this working? right, or do we need to try something else, right? So if like we're eating way too much during our eating window because we've gotten too hungry, like is this the best thing, right? If we're really sore, if we're really sluggish, if we're tired, if we feel like our blood sugar's dropping and we can't concentrate, like things like that would be red flags, but as long as we're paying attention to those things and noticing how our body feels when we're flipping, like you're saying from fasting one day to not the next day. I just really encourage people to tune in to their body, how it's functioning, their mind, how it's functioning, and just is this the best approach. Aside from like possibly feeling better, is there any benefit to exercise on non-running days like based on? Cause I hear that giving the body a rest from eating is a good opportunity for the body to flush out like not toxins, but like just repair itself or just like clear things out and just give the body a rest. Like sometimes that's what the body needs. So is there actually any benefit? apart from the performance side of things on like, just say for a non-athlete, if they're just wanting just to, if they hear that having those breaks helps clear out the body, is there any benefit attached to that? I think there is some benefit to not constantly being digesting our food, right? Like we were saying earlier, we're just in this culture where we're just eating too much, right? Too much, too long, too many hours in the day. So I think sometimes it can be helpful to reevaluate that, right? Like... Do I really need to be eating for 16 of the 24 hours out of the day? Probably not. Most people probably don't need to. So kind of evaluating like, all right, how many hours in the day am I eating? Does that make sense? Where am I eating the junk, right? So I see a lot of people who are intermittent fasting do like something from like nude into the evening. But when you really, there's a fascinating study out there that showed when you flip it on your head, people are actually more successful. So. like rather than fasting when our body needs the energy, the front half of the day, like if we're actually eating in the front half of the day and then cutting it off earlier in the evening, that can actually be more beneficial than eating late into the night, right? So I think like looking at what windows we're actually fasting in is pretty fascinating as well. And just because there's different hormones that our body's producing from a hunger standpoint and a satiety standpoint. And what the research was showing is if we're eating in the morning and cutting it off midday, that those hunger and satiety hormones decrease as the day goes on. Whereas if we're waiting and eating in the second half of the day, those go through the roof, right? So it's kind of like working with our body a little bit to feed it when it needs that fuel, which is the same concept I teach to my athletes, right? Like surrounding the hard work of our day with good nutrition, which is not six, seven, eight o'clock at night for most people. It's usually the front half of their day. So it's kind of looking at like what that eating window looks like too. Makes sense. The other benefit that I have heard in the past from intermittent fasting, apart from like a just cleaning and flushing out the body is that it trains the body to, um, to use fats as a primary fuel source. And when I was talking to Kira, she kind of said, probably not as much as people think, like it might just switch a little bit, like a couple of percent here and there favoring a fat burning, but you still need carbs, like the body still needs carbs for energy. Where do you sit on this particular topic around fat burning? Like is it really, if someone trains fasted, are they converting the body or training the body to burn more fat as a fuel source? This is a very hot topic right now and it kind of waxes and wanes in the endurance community, but I would say it's waxing a little bit more than waning recently. And you know, the one thing that I always go back to is the type of fuel that we're burning is dependent on the intensity of our exercise. So if we're exercising at a lower intensity, no matter what we've eaten, we're gonna be burning more fat. Whereas if we're exercising at a higher intensity, that's where we need more carbohydrates. So like when we look at the intensity of someone racing a marathon or racing a 5K, we're up like 75 to 90% carbs as energy. That's what our body is going to want to use or we're gonna hit the wall and our paces are gonna slow. Whereas if we're running at a slower pace, we're gonna be burning more fat. Maybe like... 50% fat, right, instead of like 15 at faster paces. So I think sometimes some of this research gets really skewed that people think I need to not eat carbs to burn fat when our bodies are like these well-oiled machines that know what intensity is to be burning, what types of fuel, and that's gonna happen independently of what we eat. Now, to your point, if we go into a run without eating carbs, we're not gonna have that substrate there to fuel, so we're going to have to use fat. So what you're saying is a lot of people are like, all right, so if I go into these workouts without eating carbs or being fasted, right, there's a lot of that like train low, train low in glycogen and carbohydrate that's really popular right now with the thought that, okay, if I don't have carbs to burn, my body's gonna have to burn fat and it's gonna have to figure out how to do it better, faster, more efficiently. And that's where the research is kind of digging into, right, is like how much of an effect does fasting going into a run, benefit our fat oxidation. And what they show is we can. We can increase how much our rate of fat oxidation when we're running, but I always tell people to go back to like, what's the goal here? Is the goal here to burn fat? Then maybe that would be beneficial sometimes, right? Or is the goal to trek across Alaska and you can't carry much fuel with you and you need to use your fat stores. Maybe that makes sense, but if we're trying to PR a half marathon or a marathon or a... you know, triathlon, we need carbs. Like it's not actually gonna do a whole lot for our body to learn how to burn fat, right? We need carbs to be able to hit those intensities. So I always try to get people to realize like what are those goals and does this approach make sense for what I'm trying to accomplish? It makes a ton of sense. Like the rationale behind it is very wise because when it comes to running, there's so many different approaches. There's so many different goals that people have. There's so many different lifestyles that people have. If someone's an elite athlete and trying to compete for the Olympics, or if someone's just a recreational runner who likes running 5k three times a week, and doesn't want to push any intensities, there's so many different varieties and so many different approaches out there. So is there any danger if someone were to, maybe if we use like a long run, if they're going to do a long run on the weekend, but it's going to be low intensity the entire time, is it, is there any danger to fasting during that particular phase? And we're just going to assume there's no like high intensity sessions or no high intensity efforts within that run. For a lot of people, there is some danger to that. So You know, especially when I look at, I guess I take a step back. So if it's a lower intensity run and we're burning more fat for fuel, can we get through that without eating? Yes, but we look at what happens if we try to push through a two or three hour run without eating. And what we find is mentally people struggle. It's harder to run when we're oxidizing fat. It feels harder. Our perceived exertion is harder. Our heart rate's higher. I mean, we usually feel a little cruddy. So mentally for somebody that's trying to go out there and crush a run, I mean, we know running is such a mental game, right? So if we feel like crap on our long runs out there, that decreases our confidence in ourselves. So for some of my runners who I know are kind of on the fence with that mental fortitude when it comes to running, I'm like, we are absolutely not running long runs fasted, right? Like mentally, that sounds like a terrible idea. And then the flip side of that too, is it's going to prolong recovery. So I mean, the research is clear. If we are going for a long run fasted, even if it's at a lower intensity, it will take us longer to recover. We have dug ourselves into a hole from a caloric expenditure standpoint, and it will take us longer to bounce back from that. I mean, I've even heard elite athletes mention this, like I gotta give myself more time to recover. And my mind is like. Why would we do this then? Do you know what I mean? Like, why do we want to prolong recovery? But, you know, obviously I'm always open to hearing other people's thoughts and views and experiences with it. But those are two of the big things that I often am like, I don't know guys about this, right? Now, if we have maximized everything else and we're looking for that, you know, extra 1%, would adding something like this in for someone make sense maybe? But like as a general rule, there's usually more drawbacks to it than benefits with most of the folks that I have experience working with. And then two, I mean, I'm sure you guys probably covered this the last time you talked about intermittent fasting is from a female versus male perspective. So we know from the research that if a man gets in the, I would call it the caloric hole, right? Like we're burning more energy than we're giving our body. If a man gets too far in that hole. Men's hormones are a little more resilient, right? Like they're going to bounce back from that a little quicker. But from a female perspective, like our bodies kind of have these alert mechanisms in them that are triggered a little bit earlier. So if it's a female who's already kind of on the fence with energy availability, maybe she's got some history of not eating quite enough, whether it's intentional or not. And then we start doing these long fasted runs even just once a week. That could be enough to throw them into that low energy availability, which decreases, you know. bone health, which can stop menstruation. I mean, it's just this whole cascade of things, and guys are a little more resilient to playing with that, whereas a lot of females aren't. And it's all just a hormonal makeup thing. So I'm obviously much more cautious about this with females than I would be with males or past injury risk. Right? So if a male has repeated injuries, I'm definitely not gonna let them go out and do long runs fasted. I think that's just a recipe for disaster, right? So like how resilient is that athlete in their past years of training? So that's something else I usually take into account too. And I think we're going to keep going back to like, it's how you feel as well. You say that some people might be able to get away with the long run, really low intensity and feel okay and maybe recover. Okay. But if someone is implementing this and like you say, they're struggling mentally through it, they're, they've got an increased heart rate through it. They're recovery so much longer afterwards. I think it does. It's probably just takes so much experimenting, which is why the topic around fasting or like nutrition in general. So many people respond so differently to different approaches of fueling and eating certain types of foods. And there's so many different reactions. And I think trying one thing, it's pretty easy to go for a run for a couple of weeks at low intensity, fasted, and then do a couple of weeks of low intensity, um, fueling a bit better and then seeing if you feel better. And then if you feel better, then maybe there's, um, warrant to, you know, remove the intermittent fasting. Would you agree with that? A hundred percent. Yeah. Yeah, and that's why I would say nutrition is never black and white and anybody who tells you it is like Put like some a guard up there, right? Like a little bit proceed with caution I guess I should say because it is it's such a gray space For exactly what you just said is everybody just responds so differently. Everyone's body is different. Everyone's history is different So it really does take some trial and error And that's why you're probably never going to hear me say yes or no to things because it really does depend right on what the person's bringing to the table. And that's why I love what I do, because we can take a look at all those elements and figure out, does this make sense for you? Yeah, I've had the mistake of fasting and doing hard workouts and just feeling super dizzy, super lightheaded. And then I just never did that again. I think I did twice. I think it took me two times to actually learn or make the correlation and say, yeah, there's something wrong here. But they were like hard, intense, like gym class sort of efforts. while fasting and it was scary. I was like lightheaded. I had to stop doing the workout. And when I mainly go for my run, which is super low intensity, I feel absolutely fine. And so I've just recognized that, you know, I'm not pushing myself in those intensities. I probably I don't see the those outcomes, like you say, about mentally struggling or high heart rate or recovering all those sorts of things. So I guess for myself, I've, I've sort of figured out, okay, here's the time I should be eating. And here's the time where I feel okay, when I'm when I'm fasting. And if I was to talk about my experience a little bit more, I used to have like this GI distress, a little bit of like FODMAP kind of symptoms. And as soon as I started intermittent fasting, my symptoms, like, I think just giving my body a break, just calm things down tremendously. And so I've kept doing that like two or three times a week, but feel great. And that's just one kind of anecdote around. how that's benefited me. But again, goes back to how you feel like someone might have the same sort of symptoms that I had try the same thing and just not work for them. It's Yeah, which is why I want so many different experts on here to talk about these things. And you do seem very well versed with the research to so it's Yeah, your advice comes very heavily weighted. I do have some patron questions come in because this is a very popular topic. You might not be surprised to hear that. No. And we might have touched on these a little bit already. But Janine asks, is there a difference in fasting for men to women in terms of when fasting should take place, if it should take place at all, I guess, based on our previous discussion? Should the windows change in terms of fasting for men versus women? So I think it just goes back to, for women, it's even more important to make sure that fast or the fasting window does not coincide with our exercise. So making sure that all right, like I work out in the morning or I work out at night, and just making sure that we can eat around that workout. I think for women that I mean, we just can't hit home enough how important that piece is. And then I do I really encourage people to rethink their window and push it more to the front half of the day, both for men and for women. I mean, when we when we look at they've done some like brain MRIs, like an fMRI, which will like, you know, light up different areas of your brain. So what they do is they had people fast the front first half of the day versus, you know, eating in the front half of the day. So they still ate the same number of calories, they still ate the same number of hours in the day. But what they found is the people who ate in the first half of the day during their fasting window, when they showed them pictures of like high caloric food, right, like ice cream and pizza and things that should light up the pleasure centers in our brain, it lit those areas up much, much less. than the people that saw that when they had the morning fast. So the people that had eaten in the evening and were fasting all morning when they showed them those same pictures, those just lit up like a light bulb on these MRIs. So what that tells us is that if we're eating more so in the front half of our day, it's changing our response to food. And in the long term, this has to be something we stick with. So if somebody is intermittent fasting and waiting to eat in the second half of the day and denying hunger, denying cravings all morning, we only have so much willpower. We're gonna end up quote unquote breaking and just eating whatever the heck we want. And from those studies, what it looks like is it'd be much more likely for someone to face plant in a pint of ice cream and a pizza if they're. denying hunger all morning and eating in the afternoon versus maybe someone would be more successful with this approach if they were eating more so in the front half of their day. Um, and again, it could be different person to person, but you know, that's the one thing that I always caution people like, let's not push that eating window too, too late in the day. Um, just so that we make sure we're successful. And just to clarify as well. So you, um, one of the recommendations for eating. more in the morning is because that's when you're more likely exercising. So you'll need the nutrition for performance, but then you'll also need that nutrition for recovery afterwards. Correct? Correct. Okay. Yeah. And then there's the whole, um, everything else that you just discussed around the cravings and the, the excitability afterwards. Okay. Um, again, might've touched on this a little bit, but if anything you want to add, um, Michelle, one of our patrons asks, is there an optimal window to aim for when running or strength training in the AM. So I guess that, that window would be just in the morning, planted around the running or the strength training in the morning. And just, yeah, making sure that we're starting to eat like an act within an hour after that workout. We should be good. The, that window gets a little bit smaller. That's probably not exactly how I should say it, but I guess I should say it becomes more imperative that we eat sooner, the older we get. So after 40 recovery is delayed, right? So if we're adding some new strength training workout and we're super, super sore, but we're not eating till two hours after, like I would be like, let's try to eat immediately after, right, for somebody like that. Whereas when we're younger, we get away with things. We have a little bit longer, a little more wiggle room to recover well. Yeah. Do you know much about Dr. Stacey Sims and her opinions around fasting and yeah, particularly fasting for females? Yeah, I followed her for probably 10 or 12 years now. She did some of the first research in women's sweat rates, sodium needs, hormones, and I'm a very heavy, salty sweater. So she kind of sucked me in with all that research probably 10 or 12 years ago. So I've been following her ever since. OK. Yeah. Because Rachel asks, what do you think about her takes on things? Because her advice was that no female athlete should be fasting. I think I don't follow much about Stacey Sims, but this is what Rachel said. But are you mainly in agreeance with her? Are there any things that you might disagree with or have any follow up questions about? Mm hmm. Stacey Sims takes a very black and white approach with all her recommendations, which, I mean, it makes sense, right? Like people want to know what to do. And she's very firm on do this, don't do that. Right? But so some of her things I think are Not necessarily I like the gray in some of these areas, but truthfully when it comes to fasting, I can get around her recommendations that, hey women, let's just not fast. Like I can absolutely, I totally understand the concerns there from a hormonal standpoint, from a recovery standpoint, from a body composition standpoint, right? Like it's a lot harder for females to maintain muscle mass as we get older, we lose it faster, we don't have as much to begin with, and we just know that hanging on to muscle mass is so important for men and women, right? So. you know, those, those fasting windows from that recovery standpoint. Um, and from that energy availability standpoint, like she's done some good research, she has, you know, lots of research cited anytime she posts about this and, um, you know, so she's definitely got the science to back up that strong statement. Um, and I can get on board with that. Okay. Maybe if this might require repeating a few things, but I just want to get my head around. when it comes to females fasting, you're saying like the hormone response is a little bit different. If someone, if a female is fasting and running, even if it's at low intensities and their hormones might not be responsive enough or bouncing back to optimal kind of levels, what might be some particular symptoms or a presentation where you're thinking maybe this isn't the best approach for you? I think probably the hallmark is a delay in menstrual cycle, whether the cycle gets shorter than 24 days or longer than, I think they say like 34, 35, something around there. So if we see a disturbance in the length of that cycle, that's like the hallmark, stop fasting. You know, that would be kind of what we would have the most concern about truthfully. But then also some things that you might notice before you have a cycle disturbance, because that can take. You know, it could happen as quick as a month, but it could take a couple of months to notice something like that. So that delayed recovery is a huge thing, you know, and I think everybody knows what that feels like, right? When we're not bouncing back, it's more than just being out of shape and trying to get back in shape. Like we're struggling. We are sore for days. We feel awful. We don't want to exercise anymore. You know, we're having trouble getting back, exercising the next day. And then also fatigue. So that just low strain fatigue. post workouts that just isn't going away versus feeling like energized, right? Like most people are like, ah, I feel so great after my run. I'm ready to tackle the day. Right. You're probably not feeling like that. Um, you know, if fasting and workouts is not going well for you. Um, but I think those would probably be some of the biggest kind of. And if this person decided to stop fasting. How long, how quick of a turnaround would you expect things to start working like their menstrual cycle to start returning to normal and fatigue levels, recovery, all that to start bouncing back? So it's going to depend how long they've been suffering those symptoms, right? So if they catch it really quick, I can often see women's cycles come back to normal within a month. But if it's been going on for a while, it can take months, it can take a while to get it back. I mean, I've had women that I've worked with, that it's taken, you know, six to eight months to get a cycle back. You know, so especially if you've lost it before, the likelihood that it's gonna take longer or be easier to lose it again and take longer to get it back. So, you know, personal history is obviously a big piece of that. But I mean, the sooner we can recognize that something doesn't feel right with our body, in any type of training, right? But, you know, specifically to this with FASTA training, you know, that's where we want to just be really in tune and truthful to ourselves, right, with how we feel. I mean, obviously fatigue and delayed recovery can be a million things, right? You know, it could be not sleeping well enough. It could be stress, you know, it could be so many things. But really just being in tune and just kind of knowing your own body and knowing when to say when and when to take a different approach. This episode is sponsored by the Run Smarter app. This includes all my free and paid content, along with housing the patron exclusive podcast episodes. You can download this free app by searching Run Smarter App in your app directory and start scrolling through past podcast episodes, blogs and videos. You'll find categories like injury prevention, running misconceptions, strength and performance, and of course, injury specific information. You've already learned a lot listening to the podcast. Why not kick it up one more gear through the Run Smarter App. I like when you say just be true to yourself because I can see An image of someone in my mind who has started intermittent fasting and seeing tremendous benefits, but then these kind of effects start slowly creeping in and they don't want to associate the two together and they just want to hold on to the initial effects of the initial benefits that they have had. I've had people say like running in. minimalist like footwear or like barefoot running shoes and then they love it. They feel so good. And then they start developing injuries and they just, I'm like, Oh, how about, you know, we swap to more supportive shoes. And like, no, I love my barefoot shoes. They just keep to it. It's probably something else. And then, um, they're, they're not really being true to themselves or at least respecting. Let's have an experiment. Let's try switching to something else for a couple of weeks or a couple of months and seeing if I feel better. Um, I can definitely see people a bit rigid with their beliefs and not wanting to away from that. So I like how you're talking about being true to yourself. And again, just like treat it like an experiment, just change things up and see if you start feeling better. And if you don't, then maybe there's something else to explore. But if you do, then you can probably start, you know, accepting the fact that maybe something should change. I see that exactly the minimal issue with fasting, because you're right, like at first, some people do see Fast body composition changes. They like what they feel like, you know, they're feeling great. They're feeling strong, but for how long, right? You know, cause at some point we're going to start losing muscle mass if we're not maximizing that recovery window. So maybe just because it worked in the beginning, doesn't mean that this is the long-term strategy for us, you know, exactly like what you're saying about the shoes, I've had this exact conversation with multiple people. Yeah. One last patron question comes from Amy. Does fasting affect injury recovery? So we talked about performance recovery, but what about injury recovery? Absolutely. So when we look at an injury, so obviously this is going to depend on the severity of the injury, but what ends up happening is we actually have increased nutrient needs when we are injured, when we are acutely injured. Obviously the bigger the injury, the bigger the nutrition needs are increased. But what ends up happening is our body is craving more to rebuild from that injury. So if we're intentionally restricting, when we're injured, it's going to delay our recovery. And this is a really common thing I see with runners too, right, like all of a sudden we can't do what we love and we're not expending all that energy that we know, you know, we need to be eating for. And all of a sudden it's like, I don't need to eat, you know, I don't need to eat as much. And when we're injured, like that's not the response that we wanna take. So I give that example because it's exactly the same thing as trying to fast when you're injured, right, it's like not giving your body the fuel it needs to rebuild and recover. And the best thing that we can do, in order to bounce back from an injury and recover that the fastest is obviously illicit help, right? Get the people on board to help us rehab that injury, but also to give our body the nutrition it needs. Because if we're in that breakdown, that catabolic state, how do we expect our body to rebuild that injury? It's just not going to happen. It's going to be much, much more slow. So we do want to make sure that when we're injured, we're taking a good hard look at our nutrition. And I'll have a lot of people come to me in that injured state, like, all right, what did I do? You know, let's take a hard look at my nutrition. Was there anything I was doing that I can change in the future to keep this from happening again? What do I need to do right now to make sure I'm healing? And you know, that's what we see. We see when we throw the best nutrition at somebody when they're down, when they're injured versus restricting, that those are the people who have the best outcomes and you know, have a less likelihood of getting re-injured when they do reintroduce that activity. Okay, makes sense. And as we finish up, is there any other... Misconceptions, any other advice that you like to have for runners? Any other final takeaways that we might not have discussed already? I think we hit so many of the big ones, right? So like, is it beneficial to do fasted runs occasionally? You know, that's a question that I get all the time. And I honestly just can't hit home enough the importance of listening to our own body. You know, I think a lot of us train in groups, a lot of us coaching groups. And it's like that group think mentality that spreads like wildfire through runners. So one person has success and we all want to do exactly what they're doing. We want to know what they did. We want to know how they did it. And that can be helpful in some respects, but in some respects, it can also trickle some pretty crummy nutrition practices through a group of people real fast. Right. So I think just like anything in life, like we want to know what our goals are, what we're trying to accomplish and really understand. Does this make sense for me and what I'm trying to accomplish here? And if you don't know that, have a discussion with a coach, have a discussion with, you know, somebody that, that you trust and value with, with your, you know, training and your goals. Um, and then, you know, seek out professionals if you need them for whatever it might be. Um, but I think hopefully people who are on the fence or trying to evaluate their own thing will get some good info from this here podcast and, uh, have a little better thought process about it. All right. Yeah. I think that's a nice summary around just. seeing how you feel, seeing how you respond. And if I could try and summarise particular like running at certain intensities. So if someone's at training, like short run, low intensity, not really requiring much recovery, then intermittent fasting might be okay. But it's all going to depend on how you're feeling, it's all going to depend on your symptoms and how you're recovering, how you're feeling afterwards. Any like both physically and mentally, if there's any fogginess. Um, however, the importance of nutrition far outweighs like the vast majority of runners, as soon as we start doing longer efforts, as soon as we just start doing high intensity efforts, as soon as you start racing or, um, yeah, performing at those higher intensities, then it's less likely that intermittent fasting would have a benefit. Absolutely. Anything to add on with that, or is that an okay summation? No, I think that's a great summation truthfully. Yeah. Cause I mean, it's really the biggest thing is. to your point, it's the intensity and it's the performance goals and you nail both those with that summary. Okay, fantastic. Is there any links you want me to include in the show notes if people want to learn more about the content you're publishing and just learn more about you and the information? Absolutely. I love to put out lots of free nutrition content. So hop on over to Instagram and my handle is Featherstone Nutrition. And then also my website is just feat and I put out all sorts of recipes. I've got some brand new recipes coming out in the new year. Every Friday I do a spot called Is That Freaking True Friday? With questions that you guys send in and we pull all the research and look at it and that's definitely the most. popular posts that I put out there so that again, you know, I'm not telling people what to do and what not to do, but here's the information. Does this make sense for you? And I think, you know, I try to empower people to have the knowledge to make those decisions for themselves. Yeah. And I've heard a few podcasts episodes when you're preaching a lot of this sort of stuff. Is there any podcasts you might recommend? Well, we have a podcast with a crew from Believe in the Run out in Baltimore, and it's called So again, we tackle user or listener questions, um, all about running and performance, and so if you have a question, you can always submit it there too. Um, but yeah, you can listen along. We're a newer podcast, but I think we're on episode 12 or 13. So there's a few out there to, to weed through. Fantastic. This has been great, Megan. I think, like I said, the, it's great to have you on with your level of expertise and your level of knowledge on this topic and always good to have a different. professional talking about their opinions and their sort of interpreting of the available evidence and I think it's helped create a lot of clarity around this subject as well. So thanks for coming on and sharing. Thanks for having me, Brody. And that concludes another Run Smarter lesson. I hope you walk away from this episode feeling empowered and proud to be a Run Smarter scholar. Because when I think of runners like you who are listening, I think of runners who recognize the power of knowledge. who don't just learn but implement these lessons, who are done with repeating the same injury cycle over and over again, who want to take an educated active role in their rehab, who are looking for evidence-based long-term solutions and will not accept problematic quick fixes. And last but not least, who serve a cause bigger than themselves and pass on the right information to other runners who need it. I look forward to bringing you another episode. helping you on your run smarter path.