Dr. Jamie Whitfield is an Australian-based exercise physiologist and postdoctoral research fellow with his Ph.D. in skeletal muscle metabolism and physiology. He is the co-author of a 2023 study, “The Use of Continuous Glucose Monitors in Sport: Possible Applications and Considerations,” and has recently been putting his research into practice with high-performance sports.
In this episode, we discuss with Dr. Whitfield the body’s remarkable ability to maintain glucose homeostasis, even in the face of starvation. We also take a deep dive into the dynamics and complexities of blood glucose and the relevance of continuous glucose monitors (CGMs) in a range of topics:
- Why and how are athletes using CGMs? Do most athletes know how to interpret the massive amounts of data to inform fueling strategies?
- Do CGMs help or hurt athlete fueling practices? What is the expert consensus on their value?
- Are there potential applications for CGMs to improve athlete health and well-being?
- Can CGMs help female athletes individualize their fueling strategies and training?
- Should the UCI ban continuous glucose monitors from competition?
We are also joined by Dr. Dana Lis, a registered dietician, performance nutritionist for the NBA Golden State Warriors, and recipient of the IOC Diploma in Sports Nutrition. She has recently launched a new company, Performance Nutrition Professionals, that trains sport practitioners on high-performance nutrition.
Dede Barry 00:04
Hi, welcome to Fast Talk Femme with DeDe Barry and Julie Young. In this episode, we’ll be discussing the use of continuous glucose monitors in endurance sports to monitor glucose levels and energy availability, and an attempt to improve health and performance. Continuous glucose monitors have been used by diabetes patients for many years. They have been proven and effective tool and helping diabetes patients more accurately monitor glucose and insulin levels. The use of continuous glucose monitors by endurance athletes is a relatively new, but quickly growing trend.
Dede Barry 00:39
Julie and I have invited two experts to join us for this episode, Dr. Jamie Whitfield and Dr. Dana Lis. Dr. Jamie Whitfield is an Australian based sports scientist who co-authored a recent study the use of continuous glucose monitors and sport possible applications and considerations which we have linked in our show notes.
Dede Barry 00:59
Dr. Dana Lis is a researcher and a practitioner, who is currently the performance nutritionist for the NBA Golden State Warriors and the World Tour cycling teams Israel premier tech and EF Education–Tibco as well as the director and US Head of Performance for science and sport. In episode 103, we discussed fueling for performance with Dana, Dana has direct experience in working with endurance athletes who have used continuous glucose monitors in an effort to optimize their fueling practices.
Dede Barry 01:29
With Jamie and Dana, we discuss whether continuous glucose monitors provide accurate and reliable information and the possible applications that might enhance sports nutrition, knowledge and performance. We also discuss important considerations and issues that might arise for an athlete who uses a continuous glucose monitor, such as the important role of a sports nutritionist and providing data context and interpretation, the challenges of data interpretation as well as bands on continuous glucose monitor use in certain sporting scenarios and the expense. Dana and Jamie, thank you for joining us today!
Brittney Coffey 02:06
Hi, listeners. We’re so excited that you’re here to check out fast talk them a new podcast series. It’s all about the female endurance athlete. Here at fast talk labs. We pride ourselves on being the pioneers of information and education in the endurance sports world for both athletes and coaches. If you like what you hear today, check out more at fast talk labs.com.
Julie Young 02:30
Hey there. Just a quick disclaimer before we jump into today’s episode. Unfortunately, we experienced some technical issues with the recording. So please excuse Dr. Whitfield’s poor audio. We hope you hang in there as Dr. Whitfield and Dr. Lists provide interesting insights on constant glucose monitors from a research and practical perspective. And now on to the show. So we’re super excited to mix it up a little bit today and have two guests joining us. Dr. Jamie Whitfield and Dr. Dana lists to discuss continuous glucose monitors, which during the podcast will also refer to as CG PMS. And I’m personally looking forward to this conversation and hearing both Jamie and Dana’s perspectives on CGM. Jamie’s perspective is based largely on his extensive research on blood glucose, fuel metabolism, and CGM. And while Dana comes from a research background, she spends more of her time now putting that knowledge into practice as a performance nutritionist. So Jamie and Dana, Welcome to Fast talk them.
Thanks for having us.
Dr. Dana Lis 03:39
Yeah, thanks so much for having us.
Julie Young 03:40
Yeah, like we said earlier, I’m impressed. We managed to juggle all the time zones with Jamie being in Australia and Dana and I be on the West Coast and DD on the east coast. So it’s pretty amazing. But anyway, we did not do justice to your backgrounds and achievements in our intro, so I’d love to throw it to the two of you to just give us a little bit more on your backgrounds and what you’re up to lately. Dana, why don’t you kick it off?
Dr. Dana Lis 04:05
Yeah, for sure. I’d love to Thanks. Um, yeah, so I’m a registered dietician. I work in in high performance sport, and I’ve been in the field for quite a while now probably just over 15 years. So have worked through the Canadian sport institutes Canadian Sport system, Olympic sport, was in Australia for a while do my PhD there. Then moved across to California did some postdoc work with Dr. Keith bar and collagen synthesis. And humans and have the last few years been trying to kind of craft my life to do all the things I love so I work with the Golden State Warriors as a performance nutritionist. And then I also work in professional cycling. So I’m working with EF Tibco SVB this year anyways, and then also started up a new company to basically train high performance sport nutritionists to work in high performance sport. So those lab to life skills that you don’t get in school. can’t really get unless you’ve worked in the field for a long time. So myself and good time friends colleague, Jen Gibson and I have started performance nutrition professionals and our Yeah, look into it sort of challenge the status quo in the US with with high performance nutrition training.
Julie Young 05:21
Excellent. Jamie, how about yourself.
So I’m Canadian, I’m did all my education in Canada. I did my undergrad at University of Western Ontario, and then did a PhD at the University of Guelph, which is about an hour west of Toronto. There, I was working on sort of looking at different nutritional and genetic interventions to impact sort of energy production and fuel metabolism. So I was working with Professor Lawrence Street and Professor Graham all the way there. And then I moved to Australia to do a postdoc in 2017. So I work now with Professor Louise Burke, and Professor John Hawley, and sort of an extension of what I was doing in my PhD, but with more of sort of, I guess, an applied slant. So looking at still energy production, but definitely applying it more specifically with elite athletes and high performance sport. They’re so sort of having some synergies there with Dana, but looking at it from more of a research standpoint.
Dede Barry 06:19
Great. It’s a real pleasure to have you both on the show. And thank you for joining us today. Jamie, I’d love for you to kick us off. And just for our listeners who don’t have experience or knowledge about CGM, could you explain what CGM czar and how they might be a benefit to an endurance athlete?
Yeah, absolutely. So continuous glucose monitors or CGM are sort of little devices that have been around for a long time now, sort of were developed in the early 2000s, primarily for type one diabetics. And basically what it is, is it’s a small device that’s usually embedded into the skin, typically, either on the abdomen, or increasingly on the back of the arm, the new sort of commercial varieties are about the size of a $1 coin, and typically just sit on the back of the arm. And basically, it has a small little sensor that sits in what is called the interstitial space. So it’s just that gap between sort of the skin and the underlying tissues. And that little sensor is basically acting as a glucose sensor. So critically, there’s no needles actually embedded in the arm once the device is, is applied. That’s sort of a common misconception around them. But what that device can do is it can provide continuous real time data. So some of the newer devices can be potentially minute by minute. And depending on what brand you have, how they sync, that data is a little bit differently. Sometimes they have a receiver that comes with it, sometimes it’s Bluetooth enabled, and so you can use your phone. And so you can sort of swipe it or if it’s got Bluetooth on, it’ll just continuously pull that data. And storage can be anywhere from sort of eight to 24 hours and or potentially more in some of the newer ones that are coming out now. So you can sort of have that on. And typically they’ve got about a two week lifespan. And so you can imagine if you’re getting minute by minute data for two weeks, you’ve got a lot of data that’s potentially coming off, and that’s going to track your blood glucose over the day and throughout the evening as well. The main benefit to this compared to sort of traditional blood glucose sampling, whether you’re looking at it from a diabetic perspective, or an athlete perspective is it means you don’t need to do continuous finger pricks. So you don’t need to sort of stab yourself, for lack of a better word. This is a relatively non invasive way, once it’s applied, it just stays on the back of your arm for the duration of the sensors life, and it’ll pull that data. So in terms of why that could potentially be of benefit to an elite athlete. Again, this was designed with diabetics in mind. The idea here is that it potentially could be a fuel gauge, if you will. So if you think about analogy being your car, what’s in your tank, you’ve got that little sensor that’s on your dashboard that’s telling you you know, are you full? Are you empty? Or do you have half a tank? That’s sort of where the the marketing NASCAR has gone with CGM is for athletes is looking at it as a real time fuel sensor. So how much glucose do you have on board and using that as a fuel to support your muscles and produce energy during exercise? And so that’s sort of where things have gone thus far. And increasingly now we’re starting to look at it from a broader sense of how may that impact health of elite athletes so we’re not necessarily worried strictly about blood glucose regulation, like a diabetic but a broader things like energy availability for female athletes in particular, potentially menstrual function. So it’s something that’s new in this space, potentially has has a lot of upside.
Dede Barry 09:50
Thanks, Jamie. So to kick off the conversation before we get into the meat of this, I want to just ask you each a few short questions, and I just want to yes, no answer. Okay, so our CGM is necessary in endurance training and racing data. No. Jamie? No. Are they helpful?
Dr. Dana Lis 10:12
Depends on the athlete. And if you have very specific outcome, and you can control all of those parameters that may be influencing. So I’d say case by case, yes. But you have to have the expertise in house to be able to use that data. Okay, Jamie,
trying to keep it to a one word answer, I’d say maybe with a big asterisk overtop.
Dede Barry 10:38
Okay. Is there a performance advantage for endurance athletes?
Dr. Dana Lis 10:43
Is that an asterix when we do?
Dede Barry 10:47
You gotta get one word answer, Stata. No more of this.
Dr. Dana Lis 10:52
That’s where I struggle. I’m gonna go with no, but maybe.
Okay. Yeah, I agree at this point. Now, maybe. Okay,
Julie Young 11:03
thanks. Good. Now, you’re gonna have a chance to really expand on those answers. But before we take a deep dive into the why, and how of CGMS you, I’d like to provide some context on the dynamics and complexity of blood glucose. And since Jamie did his PhD in blood glucose and fuel metabolism, I’ll address the questions primarily to Jamie. But Dana, anytime feel free to jump in and contribute.
Dr. Dana Lis 11:30
Yeah, no, Jamie can take this away. Okay. So Jamie,
Julie Young 11:34
first, can you help us understand energy sources for the working muscles? Yeah,
so during exercise, from its most simple perspective, body relies primarily on two fuel sources, so fats and carbohydrate, and there’s a lot of similarities between the two fuel sources. So you’ve got those fuels provided in the blood. So you’ve got blood glucose, circulating at any given time, and there’s about four grams of glucose four to five grams of glucose in your blood circulating at any given time. And that’s primarily provided by the liver. So a process called glycogenolysis. So there’s glycogen, which is stored carbohydrate stored glucose that exists both in your liver and the muscles, and the liver is gonna break that down and expel it into the blood in order to maintain those consistent blood glucose levels. You also have fat in the blood, and that’s to the breakdown and release of triglycerides from from adipose tissue, so your your body fat in other areas, and that’s going to be circulating at a given point as well. From the muscle perspective, you’ve also again got some store carbohydrates, you’ve got around 400 grams of glycogen score stored in your muscles throughout the body, and you’ve got stored fat as well. And athletes are very good at storing both of those sorts of fuels within their tissue, they’re better than sort of an untrained, sedentary inactive person, where things sort of get complicated is during exercise, the ratio of those two fuels are going to be continuously changing. So usually, it’s not an all or none thing. So this myth of you know, being in a fat burning zone, yes, you might be burning more fat and carbohydrate, but you are still going to be using sort of a blend of fuels, if you will. And as you increase the intensity of exercise, you’re going to rely more heavily on carbohydrate and specifically more heavily on the carbohydrate that is stored as glycogen within your muscles. So as you get into sort of those, those race efforts and those critical Sprint’s, etc, that’s where you’re going to be relying most heavily on on muscle glycogen, and less on those other fuel sources. So at any given time, you’re using sort of a combination of things from the blood and the things that are stored within your muscle. And then that’s going to change depending on what the type of exercise you’re doing is, as well as how long you’re doing it for. So if you exercise for a very long period of time, the sort of blend again, of fuels that you’re using is going to change over time. As you go longer, the amount of fat you use will start to increase. And that’s partly just because you’ll be running out of carbohydrate, especially if you’re not fueling while you’re exercising. And again, if you change the exercise intensity, that’s going to change the ratio as well.
Julie Young 14:18
Could you quantify in a percentage how much like glucose contributes as an energy source?
Yeah, so again, it depends on the intensity with the upper end high intensity exercise, and this will connect nicely I think to to what we talked about with CGM, you’re going to be using primarily glycogen. So for example, if you were to look at blood glucose, it’ll actually increase as opposed to decrease during really high intensity exercise. And that seems sort of counterintuitive to a lot of people because you think, Okay, I’m exercising really hard. I’m going all out here. Why is an energy fuel source that’s in the blood? Why is that increasing as opposed to decreasing and that’s just because your muscle is using glycogen as opposed to blood glucose, but you’ve still got all these signals going to the liver that are saying, Hey, we’re working really hard here, we need to maintain blood glucose. So it’s still spitting out glucose, and that’s going to accumulate in the blood and increase, but your muscles not actually taking it up. And that’s just because the rate of glycogen breakdown in the level of the muscle is so fast that it’s going to prevent glucose from coming into the cell at the same rate. So in terms of percentages, it’s again, it’s it’s kind of hard to put a specific percentage on but it’s it’s going to blood glucose will contribute throughout the exercise intensity spectrum. So even from low intensity all the way up to high intensity. But it’s going to be a relatively minor player compared to say glycogen, specifically with high intensity exercise, which is you know, so athletes that I work with are typically involved in sort of Olympic sports, specifically track and fields, everything that’s on the Olympic program, whether it’s, you know, long distance race walking, the marathon, that is all done at high intensity exercise thresholds, and that’s going to be primarily driven by glycogen use.
Julie Young 16:10
And what happens when an athlete depletes that that muscle glycogen.
So again, you’ve got about 400 grams of glycogen stored in the muscles. And so usually, that’s sort of sufficient for depending, again, on exercise intensity, anywhere from an hour, 90 minutes to two hours of exercise. So in theory, you do have sufficient energy for for quite a period of time. That’s not to say that taking on extra fuel isn’t a good thing. It definitely is. But if you were to completely deplete glycogen, you’ll have impaired exercise tolerance, impaired performance. And so some of the sort of classical exercise physiology studies that were done in the 1960s. These used a technique called percutaneous, muscle biopsies or a burn from biopsy. And so basically, they’re just taking a little core out of the muscle. And that can evaluate a whole bunch of different things with this. But basically, what they showed was having glycogen was one of the predominant things that dictated time to exhaustion during steady state exercise. So if you have people with sort of in the traditional carb loaded scenario, and had them ride the bicycle, until exhaustion, the people who have the highest amount of carbohydrate stored in the muscle would cycle for the longest period of time, and vice versa. If you had someone who had very low muscle glycogen, low energy stored in the muscle, they would cycle for the shortest period of time. So yeah, there is definitely a link between depleting glycogen and impaired exercise performance and tolerance. So being able to provide other fuel sources is going to be important, especially, you know, Dana mentioned, she’s working with pro cyclists, obviously, a marathon if you’re Lea and Khashoggi is going to take two hours, but for, you know, the average populace three hours for potentially longer, but something like a Tour de France stage, you’re looking at potentially six hours, you can’t cover that with glycogen alone. So other fuels are going to be important.
Julie Young 18:09
So is that where blood glucose comes into play in terms of once those muscles are depleted? So not
necessarily when they’re depleted? The idea here, and with most dietary interventions, when we look at it from an exercise performance perspective, and how can we delay the breakdown and depletion of that muscle glycogen? So what can we do that means that you’ve got other fuel sources on board? So, again, using a car analogy, what if we had a hybrid here? What if we had another fuel source in this case, you know, crude analogy, but the battery as opposed to just relying on the fuel fuel tank and making sure that you’ve got other sources of energy that you can rely on. So again, using Tour de France as an example, depending on the stage, if you’re in the middle of the peloton, you might be cycling along at 120 or 150 Watts, for for some period of time, because of drafting and other things, those individuals are probably going to be primarily relying on fat as a substrate, because that’s a relatively low intensity for those cyclists. So it’s about having other technical term for it is metabolic flexibility. So being able to use different fuel sources. So being able to use fat at high levels, that’s a classical adaptation to exercise training is increasing the capacity to utilize fat, but also, you know, fueling and making sure that you do have that blood glucose available. And what that’s going to do is that’s going to prevent your liver glycogen from depleting and potentially supply that muscle with fuel so that you don’t need to rely on that muscle glycogen as early again, within the context of depending on what the intensity is,
Julie Young 19:52
and you touched on this, but can you help us understand the body’s remarkable ability to maintain that glucose homeostasis This.
Yeah, so I mean that it’s an entire field unto itself. In research, there’s some people that have made their entire research career just studying single transporters that are involved in, in glucose transport. So there’s an incredible amount of complexity and nuance when we think about blood glucose control. And it’s actually pretty impressive. So I mean, again, I mentioned it earlier, but you’ve got about four to five grams of glucose circulating in your blood at one time, if you think about what that actually is compared to what you would put in, say, a coffee as an example. It’s not that much. But your body is remarkably good at maintaining that level, which, you know, there’s studies being shown that even cycling at a relatively low intensity, for four to five hours, your blood glucose level doesn’t significantly change into what would be sort of classically, deemed hypoglycemia. So that sort of red zone, if you will. So your body’s very, very good at it, there’s a lot of redundancies and backups in place. So your body also has the ability to create new glucose from non carbohydrate sources. So this is a process called gluconeogenesis. So your body can actually take fats, proteins, amino acids, and different things and through a process convert those into glucose. So even if you’re not actively feeding or fueling, your body has the ability to produce new glucose innately. And in order to maintain blood glucose control, from a muscle perspective, because that’s sort of what my background and interest is, in terms of blood glucose controls, you’ve got two different pathways to take up glucose across the muscle and ultimately use that as a fuel source first, and that is insulin dependent. So again, this is typically what’s defective or non operational in type one and type two diabetics. And so there’s a separate signaling cascade, so different activation pathways that are activated in response to insulin. And then you also have contraction, stimulated glucose uptake. And critically, those two things have some overlap, but are separate. So you know, even a type one diabetic who isn’t capable of producing insulin, contraction, mediated glucose uptake, so exercise mediated glucose uptake is still functional. So there’s redundancies but they are separate pathways. And so basically, what that’s going to do is, you’re going to activate a series of different proteins through what are known as signaling cascade. So you can think of those as little networks of switches that are communicating with each other saying, Okay, turn this on, turn that off. And what that’s going to do is it’s going to move a protein called glute four, or glucose transporter for and that’s going to move to the membrane of the cell, the edge of the muscle, and that’s basically what’s going to bring glucose from the blood, or the interstitial space into the cell where it can be utilized for other energy storage in the form of glycogen, or broken down directly through glycolysis. To produce energy.
Julie Young 23:01
Jamie, I’m gonna go back to this just to clarify. So at what point the muscle has the storage of glycogen? Yeah, at what point is that muscle going to start tapping into the blood glucose? Like, like you said, it’s not going to wait till it’s completely depleted. So what point is the muscle just continuously topping off its reserves with that blood glucose? So again,
it depends on exercise, intensity, and duration. And it’s tough to give a clear answer to that. But basically, again, there’s redundancies and feedback systems in place here. So when you break down glycogen, it plugs into this metabolic pathway called glycolysis. So basically, you’re releasing glucose into this system, so that you can break it down and produce energy for the cell. But that is also the same pathway that glucose from the blood goes into. So if you’ve got too much feedback from one side or the other, that’s going to shut the other side down. So basically, it’s called negative feedback. But if you’ve got continuous glycogen breakdown, especially during really high intensity exercise, what that’s going to do is that’s going to have a negative feedback loop towards taking in glucose from the cell, which relies upon concentration gradients as one part, but also the availability of of different enzymes and different substrates. So again, without sort of getting too lost in the minutiae, and the details of all the different enzymes and pathways. Both are happening to a certain extent, at any given time point. So you’ll be using blood glucose continuously throughout the day, even at low at exercise intensity. It’s just the relative contribution of each fuel source that will change depending on what the exercise intensity is.
Julie Young 24:47
Gotcha. Thank you. Dana. Do you want to do you want to contribute anything here? Anything to add so far?
Dr. Dana Lis 24:54
Yeah, I think just from a practical perspective, a lot of these concepts end up getting quite It’s quite oversimplified, where there’s this direct line between your fuel intake, this hormone is going to change. And you’re going to have this response. And I just encourage, you know, listeners that are looking at, you know how to optimize their fueling and adaptation to training, etc. To not get too caught up in these direct black and white scenarios of this is what’s going to happen with this fueling strategy. Your body is actually fairly smart. There are all sorts of backup mechanisms and different pathways happening at the same time to maintain homeostasis. So I think just Yeah, practical perspective. Keep it in perspective.
Julie Young 25:40
Thank you for that. So just because we are talking about blood glucose in the context of athletic performance, and what’s occurring during training and racing, Jamie, can you explain to us how like with higher intensities in that production of lactate, how lactate can affect glucose production? Yeah,
so I mean, the two things are, are intricately linked. So lactate is sort of the the logical end product of that metabolic pathway, that carbohydrate metabolism pathway called glycolysis. So basically, you’re going to take in glucose from the blood or break down glycogen. And that’s going to go through a series of different reactions and resulting in a metabolite called pyruvate. And that’s going to get converted to lactate. So that, again, whether you’re exercising at a really high intensity or a low intensity that’s constantly going to be happening. So it’s what’s known as an equilibrium reaction. So pyruvate and lactate are constantly switching between the two of them, when you’re exercising at a really high intensity, what’s going to happen is the rate of lactate production exceeds its clearance. So again, there’s a whole bunch of different chemical reactions that are involved in and I don’t think we need to get into that. But basically, that’s when lactate starts to get accumulating in the blood. And you know, there’s a whole bunch of misnomers This is probably my biggest pet peeve when I’m watching sport is someone saying, oh, you know, you can see the lactates coming out of their eyes, or you know, that, you can tell that the legs are burning with lactate, all of that is sort of old world stuff that that’s largely been disproven, you’re producing lactate all the time, there’s a lot of really nice work that’s being done now by George Brooks at UCLA, amongst others, showing that lactate as a whole host of different roles. So it’s acting as a signaling molecule, it can be used as a fuel source itself, it can get exported into the blood and used by other tissues, it can contribute to that gluconeogenesis pathway that I was talking about earlier, it can be used to produce new glucose. So lactate is doing a whole host of different things at any given time. And I think that that’s a critical thing that that people perhaps don’t have as much appreciation for as they should. And so in terms of how that’s sort of contributing to blue blood glucose, it’s not really directly tied to blood glucose control as such, but basically, what’s happening is you’ve got an increased burn, if you will, of carbohydrate. And so you’re using carbohydrate at really high rates. And that exceeds the ability of the mitochondria to utilize those molecules. So specifically pyruvate. And so what’s going to happen is it’s going to keep shuttling to lactate. And that’s sort of to maintain the continued flux through that glycolytic pathway. Again, there’s, as Dana really nicely said, there’s a lot of redundancies involved here. And so the body is really well designed so that if something is accumulating to too great of an extent, there is a way to get rid of that or regenerate it to something else so that natural energy production can continue.
Julie Young 28:49
Gotcha. And that lactate can be regenerated into glucose, not so much
into glucose per se within the muscle. But yeah, it can definitely get exported into the blog and other tissues, and then the liver could use it as a gluconeogenic precursor. Yeah,
Julie Young 29:03
got it. So in this conversation of CGM, I’ve heard this term glucose excursion. Can you explain that to us and how that might differ between a trained athlete and a recreational athlete?
Yep. So again, the key thing here, as was mentioned earlier, is context is everything. So again, I’m glucose control, incredibly complex. There’s a whole bunch of different things like even without getting into metabolic pathways that are gonna affect this. So, from an athlete’s perspective, what’s critically important is what did you eat before you exercise? What did you eat the day before you actually started? What did you eat while you were exercising? How was your sleep? Are you stressed all of these things are directly linked to blood glucose control time of day even is linked to blood glucose control. So what a glucose excursion is from the context of a CGM is basically a blood glucose Spike. where it’s rising out of a sort of perceived, potentially some brands call it a glucose performance zone or GP Zed, or sort of the the normal blood glucose range. So whether it’s spiking into what would be called hyperglycemia, or dropping into sort of hypoglycemia, so lower than what the normal levels are. And the units vary depending on whether what country you’re in either milligrams per deciliter, or minimal. But basically, the idea here is that you’ve got a unexplained rise in blood glucose or drop in blood glucose, and that sort of an excursion or, or moving outside of a normalized
Dr. Dana Lis 30:42
home. And I think that’s where there’s a lot of over interpretation or simplification, in the day to day world with athletes using continuous glucose monitors is, you know, you get these natural increases and decreases in your blood glucose levels. And a lot of people think, oh, no, what did I do? Oh, no, what happened? Oh, how did I respond? Is that good? Or is that is that bad at that time point, and attaching this good or bad thing to it, and not also considering many of the factors that Jamie just mentioned, that will affect that variability day to day. And one thing too, that I think maybe a lot of athletes forget about we know yet sleep affects it. We know your meal composition and timing, stress travel, long haul flight, but also just when we add in the data, sort of the gastrointestinal piece as well, with athletes, when a lot of you know endurance athletes are in variable levels of gastrointestinal injury throughout most of their life, how does that play a role in in what you’re seeing on your phone with your glucose data? So I think just, you know, when we’re trying to figure out what this data or this drop or this spike means, there’s so many pieces that are contributing. So you’ve in a way you’ve kind of got to run in and have one study on yourself and control those factors to get data that you can really, really trust.
Ryan Kohler 32:09
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Dede Barry 32:33
Dana, why would an endurance athlete be motivated to use a CGM? Like what are the benefits or potential benefits?
Dr. Dana Lis 32:40
Yeah, well, I would say FOMO first fear of missing out. But I mean, endurance athletes always want to find the latest tool and strategy to improve performance to get their ergogenic at eight that ergogenic advantage that they can. So I think one of it is just the nature and just the physiology of endurance athletes, especially elite like World Tour level riders, the physiology of some of those riders is really unique, where there are places when having this data may help inform, you know, better fueling strategies or different fueling strategies, or things outside of the usual box of like what we know about fuelling for different stages, etc recovery. So there’s information that we can use to help with informing, fueling and informing fuel choices carbohydrate blends, how an athlete responds to different fueling strategies. If you did like more of a fasted ride or protein fueled ride, trying to maybe get a grasp on how an athlete responds to altitude heat, and some of those, just some of the the physiological changes with regards to fuel metabolism. So in those in those conditions, yes, you could probably maybe get some data that would help inform, but I think you’ve got to have the external or sort of sports science expertise around you to really do that well, without just guessing.
Dede Barry 34:01
Yeah, it seems like a really good opportunity to individualize and pinpoint the training. Jamie, there’s been a lot of marketing and athlete testimonials circulating about the merits of CGM spit. Do you think enough testing has been done to prove their effectiveness
from a non diabetic sort of metabolically healthy, specifically with elite athletes? No, I think, again, there’s a lot of different things that are impacting blood glucose control. And one of the key things that is a potential limitation when you think about a blood glucose sensor, or a CGM is it’s only measuring one part of the equation if you will. So, overall fuel metabolism, that’s the ability to provide fuel, the ability to take up fuel and the ability to oxidize or burn that fuel. And so what a blood glucose sensor and a CGM is measuring is just the sort of rate of appearance if you will, so the circulating glucose post that’s available to a given tissue, muscle, etc. But it’s not actually giving you a direct indication of what the ability of the muscle is to take up that glucose or to even oxidize that. And so when you think about how these were developed, it was traditionally used in type one diabetics where you’re also directly injecting insulin monitoring insulin, and potentially now is, is combined with an insulin pump. So you’ve got sort of two sides of that equation in that scenario. So when people sort of develop this, that it wasn’t really with exercise in mind, because now you’re adding another layer of complexity, another level of variability to this in mind. And so I think there’s potential, that would be my biggest point is, and I think Dana hinted on this nicely is, it potentially gives rise to what you could deem the citizen scientist, everybody can be a scientist, and they’re their own no one and people like that. And I think that’s really great. And they become more invested in what they’re doing from a training and fueling scenario. And it potentially is, is super helpful for practitioners, you know, nutritionists, sports scientists, that are working with athletes, because you can get it non invasively retrospectively, so you know, an athlete can go and do their ride, they can do their training session, depending on the sport, they may even be able to compete while wearing it. And that means that you can look at that data afterwards and sort of analyze, okay, your power file or your heart rate file, or whatever physiological variable you want to do look at was doing this and your blood glucose was doing this, and you can sort of evaluate things after the fact. But in terms of how accurate they are during exercise, that’s a big caveat. And also, are they actually measuring what sort of it says on the tin, if you will? Those are sort of the big pieces there that are you know, we talked about earlier, the big asterisk over maybe,
Dede Barry 37:03
yeah, okay. And so essentially, there’s two types of CGM, there’s those that measure blood glucose. And then there’s those that measure interstitial glucose. Can you explain the difference between measuring an interstitial glucose versus blood glucose, and also kind of the accuracy levels associated with that.
So again, if you were to take a fingerprint sample, so if you were in sort of an exercise physiology lab, as an example, it’s no different than if you were getting your lactate measured. Typically, you get a lancet, you prick the finger, there’s a little drop of blood, and you measure blood glucose, blood lactate, you can measure ketones, you can measure a whole bunch of different things. And that’s what’s known as capillary blood or capillaries blood. And then what you have with CGM is it’s measuring, as you said, interstitial blood glucose. And so basically, the interstitium is that level between the blood vessels and the actual tissue. So it’s a little fluid layer that exists in between the blood vessels and the tissues. And the idea here is that that’s what the muscle or target is actually seeing. So as opposed to measuring it in the blood, you know, a blood concentration of whatever metabolite might be x, but what’s actually in the interstitium, which is what the cell is seeing, could be something else entirely. So in theory, the idea is that the interstitial space is what the cell is, is taking fuel and different substrates out of, so that should be more representative of what the muscle is actually seeing. So again, in the case of a CGM, you’ve got a small sensor that is embedded in that interstitial space. And it’s a glucose oxidase that probe and it’s basically just continuously measuring what the glucose concentration is, in that little fluid space.
Dede Barry 38:49
And so like, my understanding is that the most common sensor that athletes are using is the super Sapiens or the Abbott libre blood glucose biosensor. And it was interesting when I was reading your study, I noted that it actually doesn’t publish its accuracy level. And on top of that, it hasn’t yet been approved by the Food and Drug Administration. And so I was a little bit surprised. And you know, I sort of have heard rumblings that perhaps that’s one of the reasons that the UCI has banned them and competition. But I’d like to understand better why athletes are are using the sensor if its accuracy is not proven, and if it’s not yet approved.
Dr. Dana Lis 39:34
Yeah, I think partly, if you look at where a lot of a lot of like athletes are getting their information, are they looking at the few publications that have measured reliability and validity of some of these sensors during exercise? Both in type one diabetics and a non diabetics? Are they reading these studies or are they reading the blogs and information that comes into their email? box. And unfortunately I’d probably say the latter is where a lot of a lot of people are getting their information. So it’s not not telling the full story. You’re reading these, you know, anecdotal stories about writers that have had, you know, Revelations with their fuelling because they realized they were under fueling from their glucose data, which in some cases, yes, fantastic. But I think the reliability and validity studies that have been done, don’t tell the story that a lot of the companies want to be heard. And I still agree to just because one or two studies say it’s not reliable or valid during exercise, doesn’t mean it’s not useful. But just having the awareness that that is where the state of the research is at right now. And having that as part of your knowledge when you’re interpreting this data.
Dede Barry 40:44
Yeah. And so Dana, I mean, you’ve worked with a number of athletes, endurance athletes, specifically, who use CGM, do you feel like like practically from your experience, they’re sensitive enough to detect subtle changes in fueling status? And to positively impact like to get enough information and enough accurate information to positively impact athlete health and performance?
Dr. Dana Lis 41:08
Yeah, I sort of start on the flip side of what are the gaps? Or where are where are the areas that this athlete has room to improve from, like performance physiological adaptation piece? What do we not know about their health status, and have really actionable, sort of, I guess, your gap analysis or actionable outcomes that then we want to find information about and maybe CGM will offer some of that information. But my experience so far has been a lot of athletes will, you know, maybe get CGM is given to them or, you know, going by someone there in Europe? And when asked about hey, you know, you’re using CGM. Yeah. What did you want? What do you want to learn from it? What do you what do you think you’re missing? And most of the answers I get, I just want to learn about myself, I just want to see, see what I can learn about myself. And then they send me files and I log in and I look at, you know, these nice graphs. And I’m like, so what did you learn? Like, I don’t know, I saw a spike here, or I had this increase here or but athletes don’t know what to look for, or ask about the data. So they’re kind of like, oh, yeah, I did this for a few weeks. But I don’t know. Should I put another one in? I don’t know, my team is giving them for free. Sure. And then on also just some athletes maybe over interpreting that data without the appropriate knowledge. And with you know, some athletes that already maybe have some carb phobia, trying to ride that razor’s edge with where can I keep my blood glucose lowest, and still ride and still race and playing that game, and using it as a way to, in a way, like figure out how far they can under fuel? And obviously, the flipside to of seeing, you know, am I fueling Well, am I am I kicked enough carb on race day minus 1am, I, you know, seeing a good spike on my recovery, recovery meal after a race sort of thing. So there are, there’s flip sides, but I think a lot of times, the staff, the dieticians or the athletes do not have the expertise to use this data. And it takes a lot of frickin bandwidth to really go through the data and all of the other pieces that are recorded to use it long term. Like when I was told that someone else thinks we’re gonna be using CGM, I’m like, I don’t have that kind of bandwidth to look at that data every day and then hunt down all of the other information like sleep and travel and nutrition to actually use that data reliably and not just kind of be guessing and and be asking about it.
Dede Barry 43:36
Yeah, it seems like also, there’s a possibility just for a loss of data due to synchronization or, you know, timing issues due to synchronization, especially in a sport like cycling, where athletes are often training in really remote places where perhaps they don’t have the connection, or a good enough connection. And they missed data synchronization to expand
on one thing was saying though, like, potentially, if you’ve got minute by minute data, you’re looking at 86,000 data points per day, multiplied by the sensors lifespan, which in a lot of cases, is two weeks, so times 14. So you’ve got a lot of data that’s coming off there. And that can be incredibly useful, potentially in the right hands. But again, I don’t think the education is at the level where the people that are using this know what they should be looking for or what they need to be looking for. And so it’s definitely one of those things about making sure that you’re working with whether it’s, you know, a dietician, nutritionist, an exercise physiologist, sports scientist, whoever. But again, as Dana said, it’s a question of bandwidth. And is that going to be more important than simple things like, Hey, did you get eight hours of sleep last night? Did you have breakfast before you went? You know, I think there’s a lot of smaller things that you can take care of and even just hitting you know, this day Under revised guidelines for fueling during exercise is probably going to have a bigger impact than what a CGM can tell you. And so this is put to, potentially, you know, if we think about it, as Louise always gives this analogy of the cake, and the training is the cake. And then you know, the nutrition is potentially, ironically, the icing on the cake. CGM might be the sprinkles that are on top, you know. So it’s a very small contribution to the overall thing in terms of optimizing performance. So you know, with an elite athlete, where you’re looking for those small one percenters potentially, this is something that that can gain value for the vast majority of people, I would say, just making sure that you’re doing the small things well, and making sure that you’re fueling appropriately. Just in terms of, you know, if you’re going for more hour ride, making sure that you’re having, you know, 30 grams to 60 grams an hour of carbohydrates, or, or some other fuel, depending on the intensity, that’s probably going to do more for your performance than trying to track your blood glucose, minute by minute over over 14 day. And then in terms of your point of synchronization, absolutely. So we recently did a study looking at CGM in elite endurance athletes. And we use I think 1.6 times the amount of sensors that we expect it to you. And from speaking to other people that are working in this space, that’s pretty consistent. Again, these are just adhering to the back of your arm with basically similar to what a band aid would be. So you know, it’s a type of adhesive or glue that’s keeping it in place with a little flexible filament. So similar to like, the tip of fishing line that’s embedded in the skin, so they’re not really robotically adhered there, they do come with coverings that you can put over top that are going to sort of protect that space a little bit more, but particularly in Australian summer, that’s gonna leave some some interesting tan lines. And not everybody’s super keen on having a gigantic circle tan line on the back of their arm. So that potentially is a limitation that can so yes, so we were having athletes use potentially six or seven sensors over the course of a week to 10 days. And that was just because when they get sweaty, when they’re putting on sunscreen, when you’re getting changed in and out of potentially tight restrictive clothing, you know, lycra, etc, that that is quite tight fitting that’s potentially going to knock the sensor loose. And when you look at what the cost, and some of these things are, you know, 10 sensors over the course of a week is going to add up in cost. So if you’re not getting these supplied to you, by your team, or whoever else, a sponsor, that potentially can be prohibitive. And it’s a pretty big barrier to entry. And the other thing is the question of, you know, if it’s gotten knocked or dislodged, a little bit of potentially hasn’t completely come off, and still providing data. But is that actually still accurate? Is it telling you what you think it’s telling you? You know, we’ve had athletes where I look at it retrospectively, and according to their blood glucose sensor, they’re sitting at two or three millimolar, which is, should be slipping gradually into a coma. And I’m sitting there, and they’re sitting across from me eating a bowl of pasta. So you know, the accuracy and the synchronization things. These are critical things that, again, they weren’t necessarily designed originally with high intensity exercise, elite athletes who are traveling, getting in and out a kit, potentially training twice a day, etc. That wasn’t what they were eventually designed for. So there’s some growing pains there.
Julie Young 48:40
Jamie, I appreciate your message about focusing on the fundamentals first, because I feel like we’re in this age where, you know, and of course, there’s certain people are really like, they’re fascinated, and they’re obsessed with the data, you know, and I think all these devices that seem to be like dictating our lives right now, but really appreciate that message of there’s so many things right within our grasp of nutrition, hydration, sleep, like those are going to make the biggest difference. So thank you for that. And I was just curious, like Jamie, you had mentioned, like comparing like power meters with your glucose data. And I think this might be what what you were mentioning, Dana, in terms of kind of the labor intensiveness of this right now. I would imagine there is not a platform that is integrating all all these metrics that basically you’re having to kind of separately analyze the sleep and the the power and the heart rate. And of course, power and heart rate can be integrated. But I would imagine these are all separate platforms, or is there a platform that’s integrating all these metrics?
Dr. Dana Lis 49:43
I’d say nothing that’s integrating everything. I usually end up having to go to three different platforms sometimes for if I want to get all the pieces that I would ideally like to pull into then make a decision about about, you know how I’m informing an athlete Training peaks is doing a pretty good job with API’s, um, but still, like, if you want to really get into the data and look at the individual data points, you do need to go just individually to each of the places where those those data points are housed. And I think too, like when you’re looking at all of this data coming in, I mean, preaching to the choir here, but I’m always interested, I work in the NBA as well. So there’s a lot of load management and load metrics, which I find fascinating. A training peaks does their own version of TSS. And when I start looking at like external factors that come into the overall load of an athlete data coming at them from all of these different places, like when you work as a nutritionist or dietitian, you do you do work with the psychology of an athlete a lot. And you are you end up being quite sensitive to like how they’re responding to various nutrition strategies or data. And I’m always concerned about having another piece of data coming out and athletes, what is the return on investment on that? Is it is it going to be helpful? Is it going to be something that is beneficial for for behavior change, if I have an athlete who’s chronically under fueling can’t seem to fuel appropriately, they know they’re under fueling, but they just can’t make themselves fuel properly. You know, as Jamie mentioned, with your standardized guidelines as a start, and CGM data is that is that point that helps switch their sort of psyche around fuelling and they’re able to convince themselves to fuel better than great, then it was a good tool for that case. But do we need that data to tell us basic fueling that we know, through years and years of research is sort of standard practice? I don’t think so. I don’t think that’s where we need to start to figure out what your body needs. I think you need to start out with the basics. And then when you’re racing world tour level, and you’re the GC rider or something, then we can start figuring out what your body needs.
Julie Young 51:51
I mean, you’re so right, though, Dana. It’s so individual in terms of that that individual’s personality, you know, are they going to, is it going to be a healthy tool for them? Or is it going to be another obsession,
Dede Barry 52:02
and maybe the wrong obsession, right? Like maybe it’s someone that actually needs to be focused more on their bike handling skills, and maybe that’s where they’re going to make the biggest improvements, right. So as I mentioned earlier, you know, in 2021, the UCI banned the use of CGM is in competition in bike racing. And in March of 2023, Kristin Faulkner a female professional world tour cyclist finished third in the strata, Bianca which is a classic, you know, big big bike race in Italy, and she was subsequently disqualified for having a CGM super sapien sensor on her arm during the race. She later claimed that it was not turned on or connected for data collection during the race, but she had been using it for training, but she also issued a statement and it was quite a long statement and really, I thought quite thoughtfully put together, and she encouraged the UCI to rethink its policy in this statement, and she stated I’m going to read this, several clinical studies demonstrate that cognitive function declines significantly in a hypoglycemic state, which by the way often happens in cycling, which increases the likelihood for riders crashing in the peloton. As far as I’m aware, crashing is the most common cause of hospitalization among elite cyclists. Glucose stability is also crucial for women to maintain proper menstruation health, which she discusses in relation to the risks of low energy availability. I’d like to put this out to you. Do you agree with this statement? And if so, do you think the ban on CGM should be removed from bike races?
Yeah, I mean, similar to what we’ve been saying, I think context is, is everything I don’t disagree with. With anything that said there, I don’t think you’re getting to the level of hypoglycemia that would impair cognitive function that routinely during exercise, I mean, we’re talking two to three millimolar to have severe cognitive impairment. And again, there’s studies that show for hours at steady state exercise without any fuelling whatsoever. So taking in literally nothing but water, and you’re still sitting around for forum change. millimoles. So still, in that sort of normal range with nothing else on board whatsoever, and I’m sure Dana can say there’s not too many World Tour teams that are advocating, you know, nothing but water during a six, seven hour race, which is what strata is. So I take that point on board, I think, and Dana can speak to this better than most but I mean, the inherent nature of cycling and high performance sport is there’s always going to be a risk reward scenario. Sort of France is on right right now, I don’t know when the podcast is actually coming out. But at least right now, it’s live. You know, there was guys that craft in the time trial the other night, coming out of the starting gate, and that’s just because they’re coming in too hot and taking a too aggressive line because they want to, you know, ride that edge to get a performance benefit. They’re not crashing in the first 200 meters of a time trial. Because they’re hypoglycemic, they’re crashing, because you know, there’s a risk reward scenario there, can I go a little bit faster? Can I take this corner a little bit tighter, because the difference there and the margins of error are quite fine. Not so much cycling. But if you look at the difference between first and third, in track and field at the most recent World Championships, whether it’s 100 meters or the marathon, the difference between those medals is less than 1%. So, you know, there’s always going to be that inherent, you know, elite athletes are going to push that line no matter what, and I don’t think that’s necessarily going to be based on fueling in terms of the menstrual cycle piece, absolutely huge area of emerging research, and definitely an area where there needs to be more high quality research, specifically with endurance trained females, we know that that’s a population that’s at risk for fuelling issues and for menstrual dysfunction. But just as we were saying with the CGM is in terms of energy tracking, I don’t think the evidence is there yet that we can say, you know, hand on heart, yes, this is going to be used as a marker of you are in low energy availability. Our research group is exploring that right now. And you know, we haven’t analyzed all that data fully. But until we have, you know, validated outcomes that say, Yes, this can be used to track whatever outcome you’re looking at, and actually measure low energy availability, I’d be hesitant to say across the board, yes, this needs to be used, and all athletes should be wearing it for energy tracking, and it’s for all the reasons we’ve talked about in terms of you know, is the validity there. Is it actually measuring what it says it’s measuring? And you know, as Dana said, is this actually going to push things into a more negative space? You know, the term gluco redsea is now a thing, which is a little bit insane when you think about it, and it’s because people obsess over metrics, and this is just the newest metric. So I fully take on board what what the athletes are saying there? And I do you think there’s potential for exploring some of these topics and issues, but I don’t think the evidence is there right now to say, yes, you should be using this to track all those things.
Dede Barry 57:16
Dana, do you have anything to add?
Dr. Dana Lis 57:19
Of course I do. I get fired over this subject. I might get some hate mail after this. I mean, I have never been a world tour rider hands down. You know, you’re like I can’t speak from that perspective. And I acknowledge that. And you know what a lot of research, athletes are doing things in the field ahead of research and a lot of cases but with you know, with sort of stating that low hypoglycemia is causing crashes, and by wearing CGM, you can you know, minimum reduce that risk? I think looking at your computer for constantly looking at your blood glucose is going to be a bigger risk for crashing. And I also like a question, if you’re so concerned about being hypoglycemic and that affecting your cognitive function, if you’re fueling like an elite athlete, and you shouldn’t be getting that hypoglycemic, if you’re taking in the high end of carb intake, and you’re like at sort of best practice standards with fueling and maybe even beyond, you shouldn’t be at risk of getting hypoglycemic. Yes, you’re using a lot a lot of fuel. But I don’t think if you’re fueling well, that you should that should be a massive factor. I think there’s a lot of other factors that are going to cause a crash. And yeah, I definitely with with energy availability, but I think that that needs to be researched a lot further before we start telling people to use continuous glucose monitors to observe their energy intake. I think there’s a lot of flags that we can pick up by having dinner with an athlete of whether or not they’re in low energy availability. I could spend a couple days you know, with the team and figure out everyone’s psyche around fueling from a few meals and know how to work with each athlete to help them improve their fueling and relationship with food, etc. So I don’t think that CGM is there going to be an answer to low energy availability at this point. There’s a lot of lower hanging fruit that you need to you need to pick first.
Julie Young 59:10
Dana, I want to pick up on something you said. I mean, previously, you talked about data data overload. And then you mentioned like staring down at more data while you’re riding and for, for quite some time, I’ve had this feeling that I think a lot of the crashes can be attributed to the devices that riders are now using so much information on that device, and at 60k An hour they’re looking to see what’s coming next on the course you know, so I think this just adds I don’t know my opinion another distraction to the attention.
Dr. Dana Lis 59:45
Absolutely. That’s a long time to stay focused. Like the attention you need to ride in a world tour peloton. Again, I’ve never written there. I’m scared enough in crits. But the attention you need is is is demanding and it’s demanding on your brain in terms of glucose. You realization acknowledge that for sure, but that’s a long time to have to be super attentive and to, for that attention to go to all of these different data streams. Now, I think that’s I think that’s difficult.
Dede Barry 1:00:11
I think also, there’s like something to kind of trusting your own sense of your body and where it’s at. And I think that’s important and training, it’s also important in fueling, like, knowing, knowing the signs and signals instead of relying on a device to tell you that is important as well.
Yeah, I think to a certain extent that potentially, maybe, again, I don’t have actual evidence to support this. But I think that’s part of the reason potentially, why the UCI in particular, has banned these, you know, if you look at some of the discussions from the last, you know, 10 or 15 years, you get sort of the old world arguments of you know, power meters are bad for racing, because it’s making it more sterile, you know, the Chris room error of just staring at a power meter and writing to power. And you know, from a sport scientist perspective, absolutely, it makes complete sense that if I can tell an athlete, you know, you can hold X for this period of time, in a lab scenario that definitely is going to be advantageous, but you know, potentially on on game day or race day, there’s nothing to say that the adrenaline of the moment and the other things couldn’t push you potentially beyond that. And so staring up purely at the power meter, I know I’m guilty of this. I’ve tested myself to the nth degree. So I know exactly what I should be able to hold. But it probably in some situations may be limiting, because I’m not going to push beyond that. Because my in my head, I’m like, no, no, no, no, that that’s, that’s the red line. And cycling is pretty unique. I think that they’ve got this romanticized version of the sport in terms of tradition and other things. And so, again, with no evidence to support this, that’s potentially why they’re thinking we don’t want more wearables, we don’t want more data that’s going to say, Okay, if I push X, number of watts faster, I’m going to pop here, they want to have that spontaneity in racing. And the other thing is there, there’s patent permitted for other wearable sensors as well, you know, there’s talk of a lactate continuous monitor, there’s talk of the cortisol continuous monitor. And if you open sort of Pandora’s box to continuous glucose monitors, next thing you know, you’ve got athletes wearing every wearable under the sun and tracking every biometric possible. And while a geek like me will get really excited by all that, it potentially makes it more sterile, in terms of the spontaneity has gone from racing.
Julie Young 1:02:40
Jamie, I totally agree with you on that point about how in a race situation if we’re totally reliant on that data, we can limit ourselves and I think we’ve talked about this probably in our our episode, Dana, we spoke about this how how these devices in earlier on I touched on it but yeah, we’re just letting these devices dictate our decisions rather than inform you know, we’re forgetting like hey, let’s go how we’re feeling and let this kind of backup and inform you know, we’ve talked about the sleep monitors and how like gosh, if I get a lousy night asleep, but then it’s like, you know, self fulfilling prophecy I’m gonna stink in the race, you know, and it’s I think it can just really toy a negatively with athletes minds.
Dede Barry 1:03:23
Yeah, it can be a real distraction, I think.
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Dede Barry 1:04:03
Coming back to Faulkner, I you know, she also alluded that CGM is where necessary to better informed decision making for female athletes and their nutritional strategies to more accurately fuel and also recover due to the void of female specific research. Do you think there’s merit to that argument?
Dr. Dana Lis 1:04:23
I mean, maybe some merit in that there’s definitely a void of female specific research but some of the core foundations of fuelling so far we understand that like with carbohydrate, ingestion, digestion, absorption, that there aren’t really any significant differences between males and females. So if I’m trying to break it down to more specific what’s going to affect performance, and part of the reason for CGMS I don’t know if more female research is always going to be better but in terms of validating that comment in that snare Rio I don’t think that’s a black or white answer there. Yes, of course, we need more female athlete researchers. Everyone walking around with CGM is is not is not the answer to doing that research. There’s a lot of biomarkers we can look at to inform low energy availability. There’s a lot of psychological factors that we can observe to help inform athletes about their sort of body image relationships and low energy availability. And also just, you know, the coach athlete relationship in terms of, you know, some athletes are using CGM to, you know, kind of figure like learn about, you know, how they can stabilize their blood glucose to help potentially augment weight loss and their biggest, you know, performance determinant being their weight. And a lot of athletes aren’t at a point where that’s going to make a difference, they still need to learn how to handle their bike, whether they’re, you know, kilogram lighter is not, that’s not going to be a performance deciding factor for them, it’s whether or not they can stay in the top 15 Or, and maneuver safely. So I think that like that coach, athlete relationship, and also helping to educate coaches is important, because a lot of times coaches are or who an athlete will, will lean on for advice in all areas. And like Julie has, you know, gone above and beyond with educating herself on physiology and nutrition in every single area. So, you know, that’s an example of a coach who’s, you know, really well versed and up to date on the latest research. But um, yeah, I don’t I don’t agree with the CGM is the answer for energy availability? Not at all. There’s a lot of low hanging fruit again, start there.
Julie Young 1:06:38
Jamie, anything to add there?
I mean, I think that I would agree with all of that. Again, it’s one of those things, I think it’s, it’s a nice idea. I don’t know that there’s no evidence, at least yet to support that. And don’t get me wrong. This is coming from someone who, literally four months ago finished the study to answer that specific question. And to the earlier point, it’s a lot of data. So you know, we’ve got data from I think, 1617 athletes over 30 days. That’s a lot of CGM data to go through. But looking at it from sort of a broad, zoomed out version, I’m not seeing anything that jumps out at me, that says, yes, 100% CGM is picking up low energy availability. And that sort of circles around to what we were talking about earlier, there’s the body’s incredible at sort of having those redundant pathways in place. You know, just because you’re not necessarily consuming carbohydrate per se doesn’t mean that your blood glucose is going to drop, you know, there’s a lot of other systems in place that are going to kickstart as backups as failsafes, for backups as redundancies, to make sure that it maintains that blood glucose range, so that it keeps that, you know, four to five grams that I’ve been talking about, that stays pretty constant. There’s some very, very old studies now looking at starvation and humans. And, you know, even after a couple of days of literal starvation, zero food intake, zero caloric intake, on glucose stabilizes. So you know, the idea that this is going to be the be all and end all canary in the coal mine that is going to get low energy availability. And, you know, best I think it might help, wouldn’t be where I’m at, at this point, you know, with the obvious caveat that should new data come out. And I’m happy to take that on board and change my opinion. But I think as Dana said, you know, working with the athletes themselves, having you know, meals with them, talking to the coaches talking to sports, Sykes, being part of the embedded support team, I think that’s going to give you a lot more insight than having 86,000 data points per day is going to give you because you may be losing sort of the forest for the trees.
Julie Young 1:08:59
So let’s shift a little bit. Now if we’ve kind of covered why, let’s talk a little bit about the how, and we have talked about this, but let’s let’s take a little closer look at it. And we’ve kind of established like we don’t we’re not all sold on CGMS. But Dana, I’m going to ask you this just kind of just like humerus with this answer, if you would. Because we do know that practice often does inform science. And as you had said, the athletes are sometimes one step ahead of science. So, you know, I do know that you have worked with athletes, and can you just walk us through how like how an athlete would actually implement this into their training? I mean, we know they can’t use it in racing, but how would they implement it into their training in a useful way?
Dr. Dana Lis 1:09:45
Yeah. So I mean, when you’re working fairly closely with nutrition periodized nutrition strategy and you’re trying to optimize different fueling tools, you know, one might be you’re doing a really long low carbohydrate availability ride and trying to see how your body responds from, from a data perspective. Perception is one thing and you, you know, you might feel like I’m super hypoglycemic and but then you could look at your CGM. And if you know if the data is reliable, which again question, it could be telling you, you’re within within a normal range. And I think that in some of those scenarios, if you’re if you’re trying some sort of more aggressive fuelling strategies, you could have some data to substantiate what your body’s feeling or not feeling. I’ve worked with some athletes that we’ve done some pretty aggressive fueling strategies in terms of low carbohydrate availability, trying different protein fueling strategies, different fat fueling strategies, all the fun stuff you’d like to play around with, with cycling. And it’s amazing. Just seeing how stable when you think somebody’s definitely, they’re gonna burn out, they’re gonna drop for sure how stable your body can stay with, basically no carbohydrate on board for hours at altitude, not something I would I would advise, but when you’re at the point where you have, you know, the sports science team around you to experiment with some of those razor edge techniques and see how you respond. That’s a scenario where, you know, CGM could could offer some valuable data. I think, too, if you have enough data on yourself, and you’re a fairly habitual, consistent person, which I don’t, in some aspects, a lot of riders are, but when you look at other race, schedule, and travel, that aspect is not. But just seeing that overall, throughout the day with your normal training schedule, Mondays, this Tuesday tends to be this type of ride. And when you move to different environments, so if we’re moving altitude, or some are really hot, that could give you some general big picture overviews of maybe if there’s big changes in and how you’re utilizing glucose or your blood glucose levels, anyways, that could be a space, sometimes trying to convince riders to eat more carbohydrate, and using that data to show them like, Look, if you eat this carbohydrate, or you eat this bowl of rice, you’re still within a normal range, you’re not gonna go hyperglycaemic And then start storing body fat like that sort of, you know, trajectory that we think is very simplified. So trying to get athletes to see how their body responds. But like, Look, you need this, to fuel appropriately, this is what your body’s doing, you’re still within normal range are totally good, not gonna get fat from eating a bowl of rice, or just some of those sort of psychological pieces, I think is where CGM can help play a role with helping behavior change, because some things are very data driven. That is where their trigger point is going to be for behavior change, and seeing their own data. Not necessarily this study says X, Y and Z. But it’s, you know, some a lot of cyclists will, you know, really think that my physiology is unique, I’m a really good cyclist, my physiology is unique, I don’t respond the same as these studies, which is, is true in some cases, a lot of studies are done in, you know, recreational athletes. So I understand that. So in some cases, athletes with that sort of mentality as well, will respond better to seeing their own data, and building a strategy around their data rather than this is, you know, the latest research. And then I think also to just seeing, like, if you have an athlete who’s over fueling, helping them understand where they can periodized better, and just understanding just how to periodized better for different workloads. Do you need a CGM to do that? Not necessarily at all, it can be a tool, in some cases to just help with behavior change, or just consistency.
Julie Young 1:13:30
I’ve heard they, as you pointed out, just the individualization and like response to the different foods and like, you know, the glycemic index, and that you’re just kind of dialing it in a little bit one step further. And there.
Dr. Dana Lis 1:13:43
I mean, there is some evidence suggesting that, you know, some groups of people respond differently to the same meal, or people respond differently the same meal. That’s definitely true. So I think if some people want to, you know, dig deep, and try to fine tune some of that, but then I always try to bring it back to what’s actionable in your race and training environment. Here’s your environment. You’re in a hotel room. Not every team has a team chef. You’re in the hotel food. So is it going to mess with you, you know, you, let’s say, maybe have a longer sort of drawn out glucose spike after eating rice compared to pasta. If there’s only pasta there at the hotel menu, are you going to is that going to is that going to negatively affect you? So I think it’s important for writers to kind of take time to do some personal reflection when they’re when they jump on on the CGM bandwagon.
Julie Young 1:14:34
And I think we’ve fairly well established that, you know, this is complicated, and it’s a lot of data. And you really, for athletes to get the most out of these devices need to be supported by either a sports scientist or a nutritionist. And I would imagine to just as we’ve spoken, it’s like making sure it’s in the right hands so that person can provide the context and the perspective you know, to keep it healthy and Avoid those obsessions.
Dr. Dana Lis 1:15:01
Absolutely. And I think like, also to just recognizing when you’re starting out with inserting continuous glucose monitoring data into your already complex world, when you’re also just being aware of like how you utilize your resources, honestly, for me to really use that data well, and be confident that I’m kind of making some decent recommendations or even somewhat confident, like what I’m seeing, it takes quite a bit of data, a lot of other data, supporting what’s going on with that pink line. And from a practitioner perspective, I would probably spend, honestly, if I really wanted to do it thoroughly, that given like, you know, obviously, the issues we’ve already discussed a couple hours a day, honestly, for one rider, how much is the return on investment? What is what’s going to really change with what I recommend with your strategy? Is it big enough to warrant that that time and, and bandwidth Basically,
Julie Young 1:15:55
yes, so much data? As you both have pointed out? Bars better? No. So Jamie, and your paper, you know, and I’m gonna read the this phrase from your paper, it is important to understand and validate the algorithms or logic behind the interpretive data provided by present mobile applications for athletes, and to distinguish scenarios in which experts in sports nutrition, exercise metabolism can filter information and provide holistic or sophisticated feedback to athletes and coaches. Can you explain what you mean here?
Yeah, so a lot of these systems are black boxes, for lack of a better phrase, I don’t think it’s something that you can be passive with. But basically, it’s something that you can put it on your arm to data get sort of analyzed through an algorithm, and each company has their own proprietary system in their own proprietary algorithms that aren’t publicly available. So you don’t exactly know what’s happening in terms of how that being analyzed and what’s happening there. And then that gets exported to some sort of API system. And it presents you as Dana said, with a pretty little graph that tells you you’ve got X amount of time in this zone and X amount of time in this zone, or you have this many spikes, or this many drops, but you don’t really know necessarily where that’s coming from. And so part of it is just how the CGM themselves work. So part of it is in a traditional setting again, with a type one diabetic, what’s often happening is they will calibrate their CGM a couple of times a day by taking a finger prick and reading what the blood glucose is on their finger prick and using that to calibrate the system. The most commonly available commercially, use CGM is for athletes. So say something like the most common with a factory calibration. So at no point, are you calibrating it relative to your own biology or day to day variation, etc. So what you’re getting out of the box is what the system is. So there’s definitely some questions there about the the accuracy of the verification, I’m sure the manufacturers would dispute that. But so that’s part of it. But the other question is, you know, where are these algorithms coming from, whereas this, I mean, CGM have only really emerged in the last, say, three to five years for an athlet medic population. So where are these algorithms and this data coming from? I mean, we talked earlier about, you know, the need for more sports science research and females which agree 100%. But, you know, is this data based on females? Is it based on males? What level of training status? Are they? Are they recreationally active? Are there issues with metabolic disease, you know, for tool that’s come primarily from the metabolic dysfunction world and you know, type one type two diabetics, what is happening in that population is not necessarily going to hold true in an extremely well trained population. And even within that population, you know, you’ve got shades of gray. So the athletes Dana is working with, you know, there’s similar to me as I am to potentially a type one diabetic, you know, there’s a lot of differences in the inherent physiology there. So I think, potentially just based on the sheer volume of data that they’re getting, it’s possible, they’re refining these algorithms in the background. But as a user, you don’t really know necessarily how that’s working or, or what is happening between taking an interstitial fluid readings and how that’s being sort of exported, and compared to what a blood glucose reading would be. So that it gives you a usable outcome at the end, the gap there is is completely unknown. And so how those are being analyzed. That’s something that again, it’s something you can’t really be passive with. You need to be invested in going through your data and seeing what’s happening and, and what’s going on. It’s not, you know, as simple as a heartrate monitor. Yep, I slap it on it gives me a number off we go.
Dede Barry 1:19:58
So Jamie, we’ve talked So a little bit about some of the caveats that athletes need to be aware of such as, like the technical issues around loss of data due to synchronization issues, or the expense. And the challenges around data interpretation. There’s a couple others that I’d like you to touch on, first of all, the accuracy of measurement due to inflammation caused by sensor insertion, and then also just the potential of dislodging a sensor. And what that might mean, both in terms of safety and accuracy.
Yep. Yep, both really important pieces, I think. So when you’re actually inserting this, as I said earlier, there’s not actually a needle that’s embedded in the sensor, but it does require a needle to apply the sensor to the back of the arm or wherever you’re, you’re launching your sensor. As a result of that there will be some acute inflammation that that is associated with that. And that has been shown, again, in studies to impact the ability of the sensor to read glucose accurately, because you’ve got all these different molecules and proteins that are moving into the area in response to what is essentially trauma, you know, you poked yourself with a needle, there’s, there’s going to be a response from the body to that. And so depending on the type of sensor, you’re using, you know, the the authors of the studies and said, you know, it could be anywhere from one hour to 12 hours, or potentially longer that you might want to use that as sort of a, an equilibration period, if you will. So just sort of ignoring the data during that period. It’s just letting everything settle down, and then move from there. Some of the other researchers I’ve spoken to, they won’t use the first day as an example. So for 24 hours post insertion, they’ll just let the system settle down, let the sensor calibrate, and then we’ll start tracking the data. So I think that that is an important thing, especially when we think about within the context of cycling, where if you’ve got a crowded race calendar, and you’re not allowed to use it during a race, you’re potentially taking them off, putting them on taking them off putting them on. And so if you’ve only got, you know, a short window between races, you know, is what you’re measuring actually reflective of what’s happening at the body level. You know, if you’ve just finished the race, and you’re putting it on to try and track recovery before the next stage, chances are the data that you’re getting isn’t actually as useful as you think it is. Because what might be reading is, is that result of inflammation and other things. One of the other big caveats that I’d sort of want to bring up is we’ve been talking about in the context of stage racing, you know, Tour de France, Jiro, etc, long, prolonged stages. And that’s naturally where I think most people gravitate when they think about sort of fuel metabolism and energy production is that long duration side of things. But most events and most sort of weekend warriors aren’t going to be doing that, you know, if you’re doing a crit, potentially, you’re racing for 30 minutes, 45 minutes, and it’s going to be more or less all out. Is a CGM really gonna be able to capture that potentially not. And the other thing there is there’s a delay between what you’re actually seeing on your device and what’s actually happening at the whole body level. And so manufacturer guidelines here is it’s about 15 minutes. So between you taking something in and having that appear in your system and what your CGM is reading, there’s a 15 minute delay there. And so the analogy I use here is if you think about someone like again, this is the elite of the elite, but an Elliott Khashoggi, who’s running the marathon in two hours, he’s got fuel stations every five kilometers. He’s traveling five kilometers in less than 15 minutes, which means if he’s wearing a CGM, what he’s reading is actually looking at potentially one to two fuel stations before what he’s actually just consumed. So you know, if he’s at the 30k, Mark, is CGM is potentially giving him data of what’s happening systemically, at the 25k? Mark. So, you know, it’s all context dependent here that if you’re looking at really high intensity sport, potentially, what you’ll see is a rise in your blood glucose, because as we were talking about earlier, you’re using that muscle glycogen. And so it’s again counterintuitive, because then you’re thinking, Well, I don’t need to fuel because my blood glucose is going up. But that may again, not actually be the case. If you take a gel, for example, I’ve done cyclocross races, which are about an hour long, and if I take a gel beforehand, my CGM reads off the charts for the duration of the race. So it’s pretty hard to pull out minutiae of what I can do differently when I’m above the threshold. And so there’s sort of some technical caveats there in terms of timing of application, timing of the data that you’re getting, you know, we talked about it a little bit earlier, but synchronization issues, those those are key points, you know, if you’ve got only eight hours of storage, but you know, you’ve got really good sleep hygiene and you say, I don’t want any devices in my room while I’m sleeping. Potentially you losing some of that overnight tracking just because it’s not thinking. So those are sort of key considerations that take some some nuance and some experience of working with them to figure out. And the last point you said was sort of the dislodging thing. And we spoke about that a little bit earlier, but most of the studies that I’ve seen working with athletes have noted, you know, anywhere between sort of 15% plus failure rates, and so in some cases, that’s the sensor comes off out, right, you know, taking off a sweaty jersey or a skin suit, or whatever the case is, I mean, if you see some of the videos of the guys trying to fit into their time trial suits, it takes a bit of aerobic gymnastics and a bunch of other things to get in there, because they’re so tight fitting. If you’ve got a CGM, chances are that’s probably going to get dislodged. And in that process, no matter how much strapping you have to get it on,
Dr. Dana Lis 1:25:52
for it’s probably will take it off.
And so that, that our most recent study was entirely females endurance race walkers. And so yeah, my suspicion, without any actual practical experience here is that yeah, sweaty sports bra is probably going to be a large reason why we saw such high failure rates. So again, I said earlier, but we were looking at using 1.6 times the amount of sensors that we’re using, we went through, you know, close to 100 sensors over the course of a month. And if you’re looking at potentially 100 bucks per sensor, you can do the math pretty quickly on on how those costs add up. But beyond that, the key thing is a sensor coming off is an issue. But it’s unknown issue. So you can say okay, my sensor has come off, therefore, I will not be getting glucose data. What’s a bigger issue is a sensor potentially becoming partially dislodged or adjusting. So the filaments not sitting exactly where it’s supposed to be sitting, or potentially causing some new inflammation or whatever the case may be, and then the data that you’re actually getting, may have no bearing on what’s actually happening within your body. You know, we talked a little bit about hyperglycemia, and cognitive function and potentially causing crashes. Say the UCI had a policy where everybody needs to wear a CGM. And if your blood glucose falls below three millimoles, or whatever the case is, we’re going to pull you from the array, similar to the, say, a concussion protocol, a CGM come slightly loose, you’re getting three millimoles. As I was saying earlier, you’re sitting there having a gel or or having a sports drink, chances are, it’s an error with the sensor, not you’re actually at three millimoles. Because during exercise, that’s not really going to happen if you’re doing all the proper things in terms of fueling, that Dana spoke about earlier. So it, it’s a little bit of having that knowledge of what is normal, what is normal for you. And that can be really difficult, especially if you’ve only got a limited use of the these devices. So again, most of them are about a two week shelf life, that they’re on your arm, and then they expire. And it’s a case of usually, the sensor will stop communicating with whatever device you’re using after that two weeks. So it’s not like, Oh, this is expired, but I’ll keep using it similar to the yogurt that’s in the fridge. This is it stops working. So it’s difficult, I think, without having that education, as we’ve spoken about to actually have a really good understanding of what’s happening on. And so as I said earlier, it’s not something that an athlete or a practitioner can put on and be passive with and just say, Yep, this is gonna give me everything I need, you need to be invested in what the data are and what that means in the context and know, what is normal, what is not normal. And that takes experience. It takes education. And so working with people that have those, or investing in it yourself is critical and making sure that as Dana said earlier, you’re getting the education from the right places. So looking to get communication, that is from experts in the area, it doesn’t necessarily need to be, you know, white paper research articles. But you know, there are resources that are available out there that that can help athletes podcasts like this great example, as opposed to, you know, whatever marketing guru has has gone off. This is going to be bonk proof. I’m wearing this because I just don’t think there there’s that level of precision.
Dede Barry 1:29:16
And when do you think CGM will become more accurate, affordable and accessible? And do you think they’ll become mainstream, like similar to a power meter in cycling, for example?
It’s a good question. I don’t know that they’ll ever become mainstream. It does still involve putting something on your body that does involve some degree of pain, not that it’s it’s painful, per se, but there is a little needle prick there and it only lasts for two weeks. So again, it’s one of those things that if you like using it, and you liked the data, same thing is lactate testing. You know if that’s what motivates you to train and you like seeing your own inherent responses to your body Great all for that, as we’ve been discussing, do I think this is going to be the difference between first and second in any given race now, so I struggle to think that it’s going to be something that becomes ubiquitous across sports, because I just truthfully think that if you do the bare minimum, right, it’s not going to be an issue. So if you’re hitting standard guidelines, even at the bottom end of standard guidelines for fuelling I think that’s probably good to remove that as a major limitation in terms of you know, the hypoglycemia, the bonking, etc. In terms of costs, I mean, a big thing as you were mentioning earlier, in, you know, having something like FDA approval if you don’t have approval, it becomes very difficult to get athletes in big markets like the United States to use them as definitely a barrier right now. I think they’re definitely proved in Europe, I think you can get them now in Australia. And that’s a major consideration until they become cost effective. It’s not like a type one or type two diabetic where this is going to be something that’s necessary for you know, day to day survival, potentially, for an individual with type one diabetes, so 14 Novo Nordisk 100%, get why they need them get why they’re wearing them for the rest of the peloton. Hard to see why this is going to be critical.
Julie Young 1:31:24
Those are great. Points, Jamie. Super helpful. So as we wrap up, it seems at this point the jury’s still out on CG PMS. And also it’s, it seems that they’re currently cost prohibitive and not accessible to many people. So Jamie, let’s go back to old school and without use of a CGM. Can you offer three practical pieces of advice to help female endurance athletes maintain adequate blood glucose levels during a race?
Yeah, so I think the main thing is, is thinking about the intensity and think about duration. So if you’re exercising for, you know, only an hour, 90 minutes, maybe even two hours, chances are, you probably don’t need something during the ride, you know, if it’s just an easy spin, you’ll be fine. You know, if you want to have some sports drink or something like that, great, but you know, if it’s an hour race, like a crit gel beforehand, and that’s probably going to be sufficient from a blood glucose perspective. Once you get out above sort of 90 minutes plus, then we start looking at, okay, let’s get 30 to 60 grams per hour of carbohydrate, potentially start looking at multiple transportable carbohydrates. We didn’t talk about that, but I’m sure it’s been covered in previous podcasts. Most commercially available supplements now have that already. So you know, regardless of what brand you’re using, chances are that’s already built in. Once you get beyond sort of three, four hours, potentially, you start looking at higher fuel strategies, 60 grams plus per hour, but the biggest piece, I would say is, is yeah, just try and get something in when you can, I mean, having raised, albeit at a pretty low level, when you’re in a peloton, sometimes it’s it’s quite hard to remember to eat to fuel, you know, we talked about crashing beforehand, sometimes reaching out and grabbing a bottle, when you don’t know if there’s a corner coming up can be a sketchy thing, but trying to make sure that you’re getting in, you know, 30 grams an hour. At the minimum for a longer race, I think that’s going to take care of most things, once you’re working at the elite. And you know, I’ll defer there to Dana. But that’s where you start needing to needing to refine things a little bit more, but just trying to hit the standardized guidelines coming in with a good pre race meal. That’s going to do 99% of what you need.
Dede Barry 1:33:42
Thanks. And Dana, what would be your top three recommendations to a female endurance athlete who’s trying to optimize fueling practices?
Dr. Dana Lis 1:33:49
Yeah, as much as you can, during the year stay in energy balance and allow your body to come up and down. In terms of body weight, I think sometimes we get stuck in trying to be you know, what we’d consider race weight or performance body composition 12 months of the year. And that’s not that is not the way you’re going to have a long career. So I’d say, Yeah, energy balance most of the year, if you’re going to be in any sort of deficit, or you want to manipulate body composition, do that strategically and have you know, the physiology and nutrition support to do that? To do it properly and not be in a chronic energy deficit every single day really? periodized those blocks? And then yeah, in terms of fueling, pay attention to periodized, and you’re fueling a lot of female athletes. I think we’ll eat the same thing every day, regardless of training load or intensity. And so, yeah, periodized you’re fueling. So you’re fueling higher, lower the weight, you know, appropriately. And then I think that one of the gaps I see in racing with a lot of athletes, but female athletes, which was the question we asked about was just under fueling during racing for a number of reasons for just index perience sometimes just inability to grab a bottle or a gel, or just thinking I’m gonna wait till I get hungry or just trying to Yeah, just not practicing fueling or not liking whatever the team has. So those are factors that you a lot of them you can control with practice. So I encourage writers to like don’t let that be something that you can control for the most part. Don’t let that be a factor that’s actually hindering your performance and possibly getting on the podium.
Dede Barry 1:35:26
That’s really good advice. Thanks.
Julie Young 1:35:28
Thank you both for joining us today.
Dr. Dana Lis 1:35:30
No problem. Thank you for having us.
Dede Barry 1:35:32
That was another episode of Fast Talk Femme. Subscribe to Fast Talk Femme wherever you prefer to find your favorite podcasts. Be sure to leave us a rating and a review. The thoughts and opinions expressed on Fast Talk Femme are those of the individual. As always, we’d love your feedback and any thoughts you have on topics or guests that may be of interest for you. Get in touch via social. You can find Fast Talk Labs on Twitter and Instagram @fasttalklabs where you’ll also find all our episodes. You can also check them out on the web at fasttalklabs.com for Dr. Jamie Whitfield, Dr. Dana Lis, and Julie Young. I’m Dede Barry. Thank you for listening!