Are Supplements Worth It? The Data Behind Cycling Performance Boosters

In episode #181 we unpack the latest research in cycling nutrition with Dr. Jamie Whitfield. Learn how these can impact athletic performance, recovery, and hydration strategies across various cycling disciplines.

Key Topics Explored:

• The UCI Sports Nutrition Project and the evidence base for supplements
• Sodium citrate and bicarbonate, glycerol and ketones
• Strategies for hyperhydration

Jamie Whitfield earned his PhD in exercise physiology and muscle metabolism from the University of Guelph and is now a Senior Lecturer and researcher in the Centre for Human Metabolism & Performance at Australian Catholic University. His research utilizes a variety of research models to gain a better understanding of how nutrient availability alters skeletal muscle metabolism, and whether it can promote or inhibit training adaptation and, ultimately, human performance. He is currently an Associate Editor for the American College of Sports Medicine’s flagship journal Medicine & Science in Sports & Exercise and is an Exercise and Sport Science Australia Accredited Sport Scientist.

Please note that this podcast is created strictly for educational purposes and should never be used for medical diagnosis or treatment.

RESOURCES:

• FREE RESOURCE: Supplements for Performance Free Guide
• DIVE DEEPER: Supplements that Improve Performance Course

FOLLOW JAMIE:

• X: @jwhitfie
• Bluesky: jwhitfie.bsky.social
• European Sports Conference, July 2026

MENTIONED:

• UCI Sports Nutrition Project: Considerations and Applications for the Use of Sports Food and Supplements to Improve Performance in Cycling
• Episode 91 with Jamie Whitfield: Muscle Metabolism, High Carb vs High Fat, Supplements & Training Adaptation
• Fullscript (for reputable supplements certified safe for sport)
  • Supplements Mentioned:
    • Sodium Bicarb
    • Sodium Citrate
    • Glycerol
    • Exogenous Ketones
    • Dietary Nitrates (Beetroot)

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Transcript

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1:01

Hello everybody and welcome back to the Nutritional Revolution podcast. Today we have for you guys Dr. Jamie Whitfield and he earned his PhD in exercise physiology and muscle metabolism from the University of Guelph, Canada and is now a senior lecturer and researcher in the Center for Human Metabolism and Performance at Australian Catholic University in Melbourne, Australia. His research utilizes a variety of research models to gain a better understanding of how nutrient availability alters skeletal muscle metabolism and whether it can promote or inhibit training adaptation and ultimately human performance. He is currently an associate editor for the American College of Sports Medicine's flagship journal, Medicine and Science in Sports and Exercise, and is an Exercise and Sports Science Australia accredited sports scientist. This was a fantastic episode. You guys, covered the UCI paper on sports nutrition supplements, And if you missed it, we also had Jamie on previously on episode 91 on skeletal muscle metabolism and keto training adaptation. So if you miss that, go back and listen. This episode is fascinating. I absolutely loved it. I think you guys will do so enjoy. Welcome back everybody. We have Jamie Whitfield for you guys. He is a returning guest. If you missed our episode, I believe it was episode 91 we had you on and we were talking about muscle metabolism. So go back and listen to that folks. And thank you so much, Jamie, for returning and gracing us with your knowledge and presence. I'm very excited. We are going to dive into this exciting study that just well, article that came out. Jamie was the lead on it for our listeners. is the UCI Sports Nutrition Project considerations and applications for the use of sports foods and supplements to improve performance in cycling. So covers all kinds of areas. We're not going to get to all of it today, I'm sure, but we're going to hit on some of the the hot, hot topics and a lot of the questions I get from from clients and athletes as well. So again, I am excited to dive into this with you, Jamie. So thanks for for joining us. Why don't we start off by maybe breaking down what was this paper trying to solve? Yep. So this paper, it's a review paper that's part of a larger series. So the UCI Sports Nutrition Project is a series of review articles that are being put together by um coaches, physiologists, practitioners, people that are embedded within the sport of cycling, but also researchers such as myself. I've been fortunate that I've been working with a couple of pro cyclists for about a year now, but have a background in know, endurance sport, as well as sort of wearing my physiologist and researcher hat. So I get a dabble in both worlds, which is a lot of fun. But this project was sort of initially led by myself and Professor Louise Burke in conversations with people at the UCI about trying to pull together a consensus statement for sports nutrition for cycling. And this follows off of similar projects that have happened across other sporting disciplines. I was fortunate to contribute to the consensus statement for athletics and was a co-author on supplements for middle distance running performance um a few years ago. But other sports have done it as well, such as swimming. I believe there was one recently on tennis, et cetera. And the idea with these larger projects is really to get, um you know, isolating the evidence and the research and practice for the sport and really pulling that together. Because if you take a look at many traditional reviews, that might be pulling something from running, from cycling, from other disciplines. It might be mixed populations. It might be recreationally active athletes. It might be professional athletes. It might be people who aren't athletes at all. And so that can sort of... leave a lot of people with the question of, well, what does this mean for me? Yes, there's this research review out there that summarizes everything, but how does this apply to me or to my athlete or to my sport, et cetera? And so that's where these things are quite handy is that it really sort of narrows down to the relevant topics and the relevant information as it applies to whatever sport you're talking about. So in this case, cycling. Whereas cycling gets a little bit more complicated, is there's so many sub-disciplines within cycling. And I would say the range of physiological demands are probably even bigger than what you get in something like athletics, where you've got anything from the hundred meters all the way up to the marathon, where you've got 26 miles or 42 kilometers. But the events can broadly be grouped within sort of three, maybe four groups. And then obviously you have throws and other things which are completely different, but obviously have their own nutritional and physiological demands. With cycling, you've got events like sprint track, which can be finished in a matter of seconds, but you've also got things like gravel cycling, which could potentially be an eight hour race for some of those. the physiological demands as a result and the nutritional requirements can vary so substantially and it's very, very difficult to be sort of an expert across that spectrum. And so what we've tried to do with the larger project is sort of break those up into distinct sections. So there are individual papers that are aimed at sprint track. There's an individual paper aimed at BMX ah because the demands of that are quite unique and the the fact that athletes will be competing in rounds. And so it's not just thinking about a single session. It's also what happens with rounds, but we also have endurance track, cyclocross, mountain bike. I'm a coauthor on the review for gravel sports, but also e-sports, which is obviously an increasingly popular discipline. racing on online platforms like Swift or MyWoosh, which has a very unique power profile and therefore a different nutritional target. ah But so we've run sort of the across all the different sub-disciplines that make up the larger UCI sort of program of events. But then we also have some specific chapters. So looking at training and recovery and adaptation, we have a chapter that's on low energy availability and specifically bone health. which is an important conversation for a lot of cyclists. We have one that's been written by physicians who are embedded within cycling teams that's looking at illness and injury. And then also one that is looking at special environments, so altitude, heat, cold. And finally, also one that is looking at the role of the sport dietitian or the sport chef. m And from their perspective, what that looks like, that tends to slant a little bit. more towards road naturally. I would say road is probably the biggest and most heavily researched discipline within cycling. But we've tried to sort of have some larger umbrella articles that sort of can apply across disciplines as well as the individual chapters themselves. So I believe there's 14 chapters in all and those will be coming out in March of 2026. And those will be free to access and open access. If for whatever reason you can't contact one of the individual authors, I'm sure they would be happy to share a copy of the manuscript with you. But the consensus will sort of summarize those key themes that are emerging from all those chapters and what are the points that we're all agreeing on from. experts in the field and people who are actually working in those disciplines. So professional teams, sporting federations and NSOs, as well as researchers. And then where are the areas for future research? So where is the field going as it pertains to nutrition and cycling? What are the unanswered questions? There's still obviously a huge disparity between, the amount of research that's performed in female athletes versus males. And so that's a gap that definitely needs to be addressed. Adolescents are very underexplored. So, you if you're working with a teenage athlete or you are a teenage athlete, you know, most of this research is performed on people 18 above just because of ethical constraints at university. So there is that question of, you know, what do we do with a teenage athlete, et cetera. So. that will hopefully all come out in the consensus statement of where do we think the field needs to head and what does the next few years up to even longer look like. Amazing. Well, definitely some things caught my eye on the paper that we're going to dive into today. You broke down several supplements in the paper. Do you want to share with us what supplements you broke down and then we can dive into a couple of the hot topic ones? Yeah, mean, supplements is an interesting space. I often joke that it's what keeps me employed. Anytime I think I'm done with a supplement, something new pops up and they tend to work in Olympic cycles as well. So, you know, something that's come up and is being used sort of discreetly or, you know, we don't want to broadcast this because we think we've gotten edge. It tends to sort of emerge after the fact, you know. dietary nitrate or beetroot juice is a good example that sort of really blew up in 2016 and know, ketones would be a more recent example. ah there's no shortage of supplements and products that are out there that are sort of purported to enhance performance or health um outcomes. And so what we tried to do as co-authors for this was we really had to narrow it down because if you wanted to cover everything that's you know, being suggested to enhance performance and specifically cycling, you know, we're writing a textbook, not a review paper. So what we really tried to do was we focused on supplements that were sort of grouped as category A according to the AIS or Australian Institute of Sport um framework for supplements for athletes. And those are supplements that have a strong, robust evidence base to support their use. in athletic populations. And so I think that's one of the really key things. That framework um is easily accessible by anybody. It's on the AIS website, if you just Google, you know, AIS framework, and it breaks supplements down into different categories as you know, strong evidence is category A, category B is sort of potential but requires um further interrogation all the way down to, you know, do not use, potentially banned, that sort of thing. And so we prioritized the ones that we felt were robust and that there was good evidence base. And that was sort of our starting point. And then we also included two supplements that were sort of group B. One of them, because it can be used across different spaces. So sodium citrate, which could be used as either a buffering agent or a hydration agent, but also ketones. And the reason why we use ketones is just because it is so prevalent. in the cycling community, particularly within road racing. It's something that has been sort of lurking for lack of a better word and sort of dominating discussion, particularly in the lay media um and sort of amongst the peloton and between teams. And so we felt it was important, even though um there isn't the robust evidence base for that, we felt it was important to really interrogate that and provide sort of... what evidence there is or isn't at this point to address those points based on the research today because it's something that is really sort of dominating the headlines, if you will. I definitely have to break down the ketones, but you mentioned sodium citrate too, was another one that I did catch my eye. So you said buffering or a potential for hyper hydration. Correct. Yeah. So it can sort of dance between those two spaces. So traditionally it's used as a buffering agent. So as opposed to using sodium bicarbonate, some people use sodium citrate. So there's some longstanding research comparing the two. But there is also the potential because it has a heavy load of sodium in it. As a result, that will also result in you retaining some water. as a result, it can be used as sort of a hyper hydration agent where it will make you retain a certain degree of water, which can potentially be beneficial in competing in hot environments where perhaps water access is limiting. you know, the most probably relevant discipline with that is something like gravel cycling where you may potentially have to be self-supported. And depending on what decisions you're making with what fuel and what water you carry yourself between aid stations that might be separated by tens of kilometers or potentially even more, that's where that sort of potentially could fall into place is athletes are making decisions there of how much do I carry? What do I carry? um And again, in the gravel specific paper, one thing that came out is, those demands are not gonna be applied equally between males and female athletes, right? You know, if a male athlete is carrying a two liter bladder on their back, the fraction of that body mass is gonna be lower for them than if you've got a, you know, a 50 kilo female racer who's carrying that same water hydration pack, that's gonna be a higher proportion of their body mass. And so the decisions that they might make for their fueling nutrition and hydration may differ as a result of. sort of balancing those demands. And so then, you know, an athlete might consider something like a hyper hydration protocol to sort of help with that aspect of things. This is very fascinating. So a couple of questions already. So is it a similar dosing protocol with sodium bicarb versus sodium citrate to have the buffering effect? Give or take the sodium bicarb. So again, one of the things that we've really tried to emphasize within that review paper. So the supplement review is we've provided tables that sort of try and break down and digest the information as easily as possible. So we have a table in there that sort of outlines what are the sort of current dosing strategies that are recommended in terms of, know, how much do I need to take? sodium citrate or sodium bicarbonate, but also when do I take it? How long do I need to take it? How long is that going to be in my system? Those sorts of things, as well as critically, what are potential side effects to those supplements? So with sodium bicarbonate, the sort of standard recommendations are 0.3 grams per kilo body mass, so 300 mgs. With sodium citrate, it's a little bit higher, so about 0.5 or 500 mgs. So comparable, the timelines tend to be about the same as well. Side effects between the two tend to be quite similar as well in terms of predominantly with sodium bicarbonate and sodium citrate. You're looking at GI upset is sort of the most common complaint, but that's sort of again outlined within the paper. Okay. And so I have seen like a lot of hydration products or electrolytes that will use the citrate form of sodium in their product. One's not getting a buffering effect from 500 milligrams of sodium citrate. So if you're only taking 500, that would probably be quite low. So again, with any of these things, with any supplement, regardless of what type of supplement it is, you basically need to have enough of it in your system in order to elicit some effects. So if you're looking at something that you would take acutely, so on the day of in order to influence that day's training or that day's performance, things like Caffeine are a great example of that, potentially dietary nitrate, sodium bicarb, et cetera. You need to have enough of that in your system that it can do whatever it is supposed to do. So when we're looking at a buffering agent, so sodium bicarbonate or sodium citrate, you need to have enough of that in your blood plasma in order to act as a buffer and sort of negate some of that acidic buildup that occurs with exercise and particularly high intensity exercise. with something that is a chronic thing, you need to have elevated levels over time in order to push that into whatever its target is. So if you're looking at something like a beta-alanine or a creatine, that already exists to a certain extent within your muscle. That's where we wanna try and get it. So you need to elevate the levels in circulation in order to sort of drive that into your muscle through diffusion gradient. So basically if it's higher concentration in your blood than it is in your muscle, Hopefully what will happen is it will get pushed into your muscle and accumulate there and that's where it can have an effect. if you're only taking a very small amount of something, caffeine might be the exception in terms of these dietary supplements. If you're only taking one tablet of a hydration product, that's not gonna have sufficient levels of, as you said, sodium citrate in order to have a buffering effect. In that case, what it's trying to do is increase the amount of sodium that you're taking in because obviously when you're sweating it's not just water, you're also losing electrolytes. So what these hydration products are ideally trying to do with varying degrees of efficacy is provide some of those electrolytes back. So know, same idea if you go to a pub or something like that and there's a bunch of salty nuts or salty pretzels on the bar, that's going to make you thirsty, it's going to increase your desire to drink. that will also help hopefully retain some of that water, depending on what you're drinking, obviously. um Same idea with these electrolyte tabs. hopefully it will stimulate drive to drink, but also help you retain some of the fluids that you do ingest. Because if you just drink pure water, um some of that is ultimately just going to be lost as urine. So trying to retain that. And again, there is an excellent chapter within within the series um on special environments, which covers heat, that is written by sort of experts in those areas. And they do a lot of really nice work on hydration and what is the role of drinking to thirst versus having a drinking plan for various disciplines, et cetera. um And so we try and across all the different reviews, refer readers and athletes and coaches to... wherever the most pertinent information for that specific topic would be because again, you can't cover everything within one paper. Yeah, amazing. Okay, so now I have to ask you mentioned sodium citrate as a hyper hydrator. Are you also getting fluid retention from a sodium bicarb? To a certain extent, you will get some. The doses are different. So if you were taking sodium citrate for a hyperhydration, you would be increasing the dose. So then you're looking at two to four grams of sodium citrate as opposed to the smaller dose when you're looking at the buffering agent. And you're consuming that with fluid as well as opposed to just potentially looking at that as a individual capsule, perhaps. So again, that's sort of spelled out within the review, but how you take them will differ depending on what sort of your intended outcome is. Most of the work, especially recently that's been done has really prioritized sodium bicarb over sodium citrate. Again, you're taking a lower load of the two and that also probably means you're consuming less overall sodium, which is probably a good thing. Again, there's no... long-term effects that have been documented to this that are a negative for overall health. yeah, most of the literature currently has sort of pivoted more towards a sodium bicarb, but we felt it was important because both have been used classically to sort of give information on both forms. Awesome. And what would the case or use case be or maybe sport type duration temperature for someone to do hyper hydrating? And then when would they do that hyper hydration protocol? Yeah. So again, one of the things we've really emphasized, I think, or at least I hope throughout the review is the need that everything is sort of a case by case basis. And certainly within the consensus document, which is being written currently. So I'm speaking ahead of turn, but we've tried to provide a go or no go sort of flow chart of, you know, for us as researchers, but also as practitioners, what is sort of our logic step. or logic tree in terms of how we address these. But with any supplement, it's always a case by case basis of figuring out what works for you or for your athlete. With something like a hyperhydration protocol, again, it depends. Different athletes will have different sweat rates, different tolerances for consuming fluids or not. But within cycling, it's really unique is that the opportunities to fuel will differ. For someone that's doing a standard road stage, there's ample opportunities to carry fuel on your bike, but also replace those by dropping back to a team car or a domestic on the road, or sorry, a soigneur on the road who's handing out bottles. Maybe one of your teammates shares a bottle, neutral support, et cetera. Again, this is more of the professional side of things as opposed to the sort of your weekend warrior or amateur athlete. um Whereas something like gravel, that differs not only to road but within that sort of sub-discipline. There are some events that make aid stations mandatory stops, so you have to stop at those aid stations and therefore you may as well refuel, grab more bottles, whatever. Some races do not have that and so an athlete may elect to try and get competitive edge by pushing through that aid station and not refueling. There are also differences that athletes in gravel can carry hydration packs, whereas at least at present, those are not allowed in the road. So there are sort of sub-disciplines and sort of evaluations and choices that you need to make there. I alluded to it earlier in terms of some of the differences between males and female athletes, something that hadn't occurred to me until we were actually writing the article and for the gravel and e-sports, so racing on those online platforms, there's not really any literature at present for those disciplines because they're so new. They've been exploding over the last couple of years. So it was a little bit different in terms of how we approach that and very much a case of, well, what evidence is there? And so instead of trying to go to the literature, we went to the athletes themselves and interviewed athletes that were racing internationally in those disciplines. and said, well, what are you doing? Where are you getting this information from? Are you supported by a team, et cetera? And one of the things that came out that I had never considered is that if you're a female athlete, your frame is smaller. And so you may not actually have room for the same size bottle of fluid on your frame that a male athlete would have. And so again, that's another example where... the nutrition and fueling and hydration demands are gonna be different from them because they don't have the same opportunities to carry the same things. And when they do carry the same things, there are potentially a higher weight penalty to that in terms of, well, now if I'm biking up a hill, I'm also carrying two kilos on my back and 1.5 kilos in my bottles, those are trade-offs. So. long-winded way of getting around ah to when would you use this? The unattractive answer is it very much depends because it will be a case of what is your tolerance? For someone like me, I am both a high volume and high salt sweater. So I really suffer in the heat, which I discovered firsthand by moving to Australia and have sort of enjoyed that ever since. But for other athletes who are potentially lower volume, sweaters, that may not be as much of an issue. And then again, the decision is, well, okay, can I afford to be carrying additional sort of body weight for lack of a better term, because with hyper hydration, the idea is you're retaining additional body water. And that will sort of give you a greater Delta before you hit that sort of critical dehydration point where it's starting to affect performance. So if you've got extra body water, you can dehydrate more before it starts negatively impacting you. But that will be very much a case by case basis in terms of when athletes do it. Again, this is laid out within the paper, but typically the hyperhydration protocol would take place an hour to 90 minutes sort of before the start of exercises traditionally when it's done. And again, that's done in combination by consuming either. something like glycerol in a fixed amount or potentially sodium citrate alongside water. So the idea is sort of having that and being able to consume that. The downside obviously being that there will be a certain degree of, you know, bloating, nausea, body mass gain because you are retaining that extra water. Some individuals feel headaches as well, but that's where, you know, not doing this for the first time on a race day is again an important decision and something we've sort of reiterated throughout the paper. I had heard of doing hyper hydration to the night before an earlier morning event. Do you pee off some of that? Do you think? you, you probably would. Um, so we, we haven't published it yet, but we've actually tried to do something like that recently in, our lab where we basically had athletes perform dehydrating exercise in the afternoon. because, this, this was based in athletics, not cycling, but often those athletes will train in the afternoon and particularly here in Australia, it's, it's very, very hot in the summer in the afternoon. and then rehydrating according to what sort of guidelines are. So traditional guidelines are 1.5 times your body mass loss is what you should be rehydrating with according to sports nutrition guidelines. If you're someone like me that loses a lot of sweat, that becomes a lot of fluid. So if you're losing two or three kilos over the course of an hour or two, then multiply that by 1.5 suddenly, you're looking at drinking a lot of fluid in order to get that down. And the downside to that is you're probably going to be disrupted in terms of your sleep just because you're getting up throughout the night in order to pee. And so that's where, you're looking at a major competition, doing something the morning of, if it's applicable, if your event starts at. 6 a.m. than getting up and doing a hyper hydration protocol an hour and a half beforehand, it's probably not feasible. But trying to prioritize sleep, think depending on the outfit, you're probably going to get more bang for your buck in terms of making sure that you got a good night's sleep the night before event versus m having a bit of extra water delta to play with on the dehydration front. Yeah, OK. That's super helpful. I appreciate you breaking that down. And I do want to touch quickly on glycerol and then definitely ketones before I got to let you let you go here. But can you talk to us a little bit about glycerol? Because for the longest time, glycerol was banned. So people were not able to use it in sport. Can you just share with us maybe why was it banned and then how is that a tool we can use now? Yeah, think this isn't based on full knowledge of all the details with glycerol, but I think a lot of it is because it retains water. The concern is that something like that could be used as a masking agent. So in order to sort of increase your blood volume and perhaps sort of dilute anything else that might be in there that's not supposed to be in there. ah So certainly from a WADA, a World Anti-Doping Association perspective or USADA, depending on where you're based, that is a concern. It's the same reason why there's limitations in terms of how much you can infuse a professional athlete that is under WADA jurisdiction. know, IV bags and things like that, that is a prohibited method. I think it's capped at 50 mils an hour or something like that. but so that that's part of the reason I suspect why that was, was done. whereas glycerol now is, is allowed just cause I'm again, I'm not the expert on this one. This, section was led by Juan Del Caso, who, who is an expert in, in hyperhydration. But, my guess is that again, as the science has evolved the the sensitivity of instrumentation in order to pick things up has improved. so therefore people have realized that what you're getting from a glycerol loading protocol is not going to be sufficient to trigger any issues with anti-doping. Very much the same thing as caffeine. Caffeine was a banned substance for a long time. And then the current recommendations for caffeine supplementation are so far below what the old trigger was for antidoping that it becomes a bit of a moot point. Caffeine obviously has the other aspect that something that people consume in the morning globally in coffees and teas and other things. So that's sort of why glycerol sort of came back into the fold. I think it's something that has been around for a while, but perhaps has not been. ah as popular or as front of mind as a lot of the other supplements. And part of that is probably just because it's a little bit trickier to do. You know, can't just walk down to a chemist or a sports nutrition shop and buy some glycerol off the shelf. It's certainly harder to attain. And that's where you're probably looking at working with. know, a national sporting organization or a researcher or something like that. And that's where it tends to get sort of prioritized. And so, yeah, so it's been off the prohibited list since 2018, I believe. And so as a result, in the last sort of seven, eight years, the research side of that thing, things has really increased. And so there's a group based here in Australia led by Amelia Carr that that has done a lot of great work in that area, as well as other groups throughout the world. But the idea here is that we're creating an increase in that fluid retention, as I said. And the idea there is that if you've got more body water, then you can dehydrate as you do naturally with exercise through sweat and other things. But you've got a higher sort of threshold before you reach that critical junction where dehydration starts impacting performance. The often quoted percentages is around 2 % body mass is where you start noticing body mass decrements. In something like a marathon, you can probably go beyond that and still be fine. With cycling, again, depending on the discipline, things are moving a lot faster. There are decision-making choices that need to be made that go beyond simply, I maintain this pace or can I chase that guy down? okay, if you're doing gravel, there's a technical section here, I need to be focused and making sure I don't crash or I'm on a mountain descent and there's switchbacks and we've reconned this but there's one corner that's really tricky and so the cognitive component which is something that definitely suffers with dehydration, that becomes much more critical I think in a cycling based discipline than some other ones. And so again, that's where you can start seeing something like glycerol potentially being a benefit. So glycerol, depending on the study, can increase fluid retention by about 40 % in some cases. And depending on what study you're looking at and what discipline, that can be resulting with improved cycling performance by maintaining a higher power output over time. And part of that is linked to just you're not dehydrating to the same extent and crossing that critical junction. That's sort of the basis of that. But again, the mechanisms of everything in those sort of details for each of the supplements that we cover in the review are really spelled out in greater detail in the review. And we'll link the study for the listeners too so they can dive into all of that. So just really quick to clarify with the glycerol, is the mode of getting it into the body, the only option is IV? Okay. Okay. Apologies if that was sort of, so yeah, so we're definitely not recommending anything that requires any sort of injection, any sort of needles whatsoever, full stop. We do a lot of work with the AIS and AIS has a strict no needle policy, which I think is a fantastic thing. So no, so in this case it's drinks. So you're mixing glycerol, with a volume of fluid. So it's one to 1.5 grams per kilogram body mass of glycerol in combination with 15 to 30 milliliters per kilogram of water. So it comes in a liquid form. So it's drinking. So it's purely just consuming orally via drink. So glycerol just, if anybody hasn't seen it, it looks like a heavy sort of... clear version of maple syrup would be sort of the best example of it. So it's quite viscous. It's a thick fluid. So when you pour it, it doesn't splash. sort of oozes, for lack of a better term. So very much like maple syrup, but it's clear. And so you would consume that along with water. So you're drinking it. Yeah. And that is similar like 90 minutes before sport. So yeah, one to one and a half hours before is sort of what the traditional guidelines are in terms of the research with the obvious caveat being, know, trial it ah beforehand, figure out how that feels for you because some athletes, again, they may have some GI upset, bloating, feelings of nausea. And obviously you don't want to be sitting on the start line feeling that already. So making sure that you have time to load it because that again can be quite a high volume of fluid that you're consuming. And so making sure that you have both the time to load that if that's the strategy you're employing while still hitting that start line feeling ready to go and able to perform at your best. Yeah. Okay. That's great. Okay. I want to jump into ketones. There's obviously that's your area of study too, or that you wrote for the paper. So I'd love for you to break that down for us. I know there's been ketone use looked at before, during, after Endurance Sport. What was the takeaway, the form, the dose? Yeah, so ketones are a fun one, I think. So I wrote this section along with Dr. Brendan Egan, who's an expert in ketones as well, who's from Ireland and has done a lot of great work in this space. So he and I wrote this section together. And one of the things that we really tried to do was pull together m cycling-based studies. m things that were specific to cycling that have really targeted this. And unfortunately for ketones, that's probably the discipline where ketones have been used the most is cycling. And if you look at road teams, there's several road teams currently as well as historically that have had a ketone specific sponsor. So as opposed to just your standard sports nutrition supplier, whether that's science and sport or 6D or... precision, whoever the company might be. In this case, some teams actually have a specific ketone supplier. The way I've sort of described it in talks previously is that ketones are a little bit like that old sort of carnival game whack-a-mole. As soon as you sort of are finished disproving one thing that ketones are allegedly doing, something else pops up. And well, no, wait, they're actually doing this. So that might be sort of burying the lead a little bit, but the gist of it is, in my opinion, there's not any strong evidence to support using ketones full stop. So the original research that sort of delved into this, and sorry, full stop for athletic performance. I should add that caveat, because they are applied in other contexts. The original sort of sports science research on this was that ketones were providing an alternative fuel source. So, you know, we've spoke together previously about metabolism and manipulating carbohydrates and fats. Those are sort of our two traditional metabolic fuels or substrates. That's what your body is breaking down and burning in order to produce energy. And there was a study that came out in 2016 that suggests that maybe ketones was a third option. So your body does produce ketones naturally through periods of carbohydrate restriction. ah If you went on something like an Atkins diet, for example, or a ketogenic diet. So as the name implies, you're producing ketones by restricting carbohydrate intake. But also if you were to do a prolonged fast and didn't have access to food for a long period of time. your body will take excess fats and lipids and then the liver will convert those to these molecules known as ketone bodies. And those can enter circulation and be used by other tissues. The brain seems to like ketones. There's some evidence that the heart will use them as well. But the idea was that maybe muscle is using these to fuel exercise. Now, obviously, if you're taking an elite athlete, you're not going to say, okay, I'm going to make you fast for three days in order to get your ketone levels up. And then you're suddenly going to be using ketones because obviously that's not going to be an ideal fuel prep prior to exercise and performance. So there's a group of researchers that developed what are known as exogenous ketones. basically fancy way of saying there's a supplement version. So you can consume these supplements acutely. So the day of and within a matter of 30 minutes, your circulating levels of ketones are going to elevate higher than what they would with chronic carbohydrate restriction or fasting. So after an overnight fast, your circulating levels of ketones might be 0.1 millimoles. So that's just the concentration of the ketones that are in the blood. you're to consume a ketone supplement that might go to two or three millimoles. So you know your orders of magnitude higher just by consuming this supplement acutely prior to exercise. So that was an interesting concept and that's really what sort of started this entire field of research and as I said that was 2016 so we're about 10 years into this now. For me the the way I've sort of always approach this is, well, from an evolutionary perspective, how would that work? Why would your body say, hey, I've got this thing that I would only ever see if I was starving. Why would I prioritize using that fuel over everything else that I have in my body, know, stored glycogen, stored fats, circulating blood glucose, circulating lipids, all those things are still there. How would this work? So it was a very interesting question for me. And the research over the last few years, in my opinion, has sort of ruled out the idea that it's your muscle, at least, is using it. That doesn't mean that your brain isn't or your heart isn't. Those are obviously a lot harder to evaluate in intact humans and during exercise. But there's been some really elegant work that's been done that has shown that your muscle doesn't really use ketones. So there's a paper by a Canadian researcher, Heather Petrick, out of the University of Guelph, which is my alma mater. And she did some really, really nice work showing that when you provided skeletal muscle mitochondria, so where you're actually producing that energy within your muscle, if you provided those with pure ketones, they don't really do much with it. If you then threw a bit of carbohydrate-derived fuel, on top of that, suddenly your mitochondria go nuts and they start producing energy and consuming oxygen. And so at the same time, there's a paper that came out from the original research group that had published some of the early work and they used a ketone tracer. So basically you can think of this as providing that supplement, but it's got a sort of tag on it or a flag. So you can follow it as it's going through circulation. And then if you take blood samples or breath samples, you can figure out, are we actually burning what we gave you? So can I detect that tag or that flag in your blood or in your breath sample? And where is it going within the body? What are you using with it? And that study showed that it peaked as a percentage of overall energy production at, I think around four to 5%. And that was at very low intensity exercise. I'm talking in the order of magnitude of like 100 watts. When you consider that, you know, a pro male cyclist might be averaging in excess of 300 watts for four hours, a 4 % contribution at 100 watts, probably not budging the needle all that much. And that's being replicated now by other groups in different contexts. And so I think the ketone literature is a bit of a mess. There's a lot of conflicting evidence about there. And so that's part of the reason why we, myself and Brendan and others really wanted to include that here. And so to my mind, the state of the field at present is that there is no robust evidence to support the use of ketones to improve same day performance. So it's not something that you're gonna take. before or during a race in order to improve performance that day. Where the field has sort of pivoted to in the last couple of years has been the idea of ketones for recovery. And this stems out of a study that was done that showed that it perhaps reduced some of the symptoms and development of overtraining. So when athletes consumed ketones or a placebo as part of a structured overtraining protocol over the course of I think it was three weeks. The individual supplementing with a ketone maintained performance better and improved better, were able to complete training better and other signs and symptoms that would be associated with overtraining were suppressed. So then this was, okay, well maybe we just need to be consuming it after exercise and that's going to enhance things. The sort of major caveat to that study is the athletes that were consuming a ketone also consumed substantially more overall energy as part of this. So the diet wasn't controlled and that's just part of research. You know, you can't control absolutely everything in every study. That's why you do follow-ups and other things. And controlling diet, especially over the course of multiple weeks is very, very difficult and very, very expensive. But part of that was most of the extra energy intake was in the form of carbohydrate. So now you've sort of got a situation in which these athletes are fueling to a greater degree, whether that's because of the ketones or in spite of the ketones, it's impossible to say, but a lot of that is also carbohydrate. So is it a case that their training is being maintained because they're fueling for the work required? exercising harder, they're doing more sessions than they normally would, but they're also consuming more energy and more carbohydrate to support that. And therefore they're adapting and improving over the course of the training block, as opposed to, we've taken this little supplement and that's what's actually blunting all these negative signals, et cetera. And so that's where the field gets a little bit murky. We've done some work in our lab. looking specifically at what happens to cellular metabolism with consuming a ketone supplement after exercise. And in our hands, there's no difference. And this is being replicated by some work from Jose Hereta's group in Liverpool, John Moores in the UK. And they showed the exact same thing. So they gave ketone supplements after exercise and they used a technique called Trans-Syp- transcriptomics, excuse me. So what they're looking at is after exercise, we switch on all these cellular signaling networks and that leads to activation of gene expression. And hopefully over time, we take those gene transcripts, we turn it into functional protein and that's what leads to adaptation. When at least again, in an acute scenario, there was no difference between placebo and ketone supplement in terms of the overall transcriptomic. So instead of just looking at one or two different targets that we know should be upregulated, they looked at a global panel. So it was an unbiased panel. So we're looking potentially in the orders of hundreds or thousands of different transcripts. And there was no difference between the two treatments. In our group's research, we did a targeted panel, but we've also looked at cell signaling activation. both upstream and downstream of that. So things that could impact adaptation, again, there's no difference. So in my opinion, based on sort of the evidence as it stands currently, as we're having this chat, again, this may evolve. There's also no evidence that for me would support if I'm working with an athlete that I would say you should be taking ketones post exercise because this is going to enhance your recovery. The other sort of part and parcel to this is ketones are quite expensive. ah And if anybody's taken them, they're pretty unpleasant to consume as well. They don't taste very nice. If you've ever smelled nail polish remover, acetoacetate, that is a ketone. That's what these smell and taste like. There are some flavored forms, I think, on the market now, but they're not the most pleasant thing in the world to consume. And so if you're not seeing a positive benefit during exercise, you're not seeing a positive adaptive response after exercise. For me, something that is expensive, not so nice to eat or drink and isn't having a huge benefit that that for me is enough to rule it out entirely. So again, this may, this may change, this may evolve. The one thing we haven't talked about is there is some evidence, and again, this is very mixed, not every group, not every study shows this, but there is some evidence that it could increase EPO secretion. So this isn't, again, this isn't doping, this isn't you're injecting EPO, your body naturally produces EPO as part of a training adaptation response, particularly with things like altitude. But again, this is not consistently. shown across every study. That study I alluded to earlier from Jose Reda's group, they did not show an increase in EPO secretion. And in our hands, in our study, we also did not see a change in EPO secretion post exercise. And in our study, we followed it for five hours post exercise. So I don't think there's a strong evidence base right now that if I'm talking to a coach or an athlete, that I'd be like, yep, this should be in your toolbox. You should be considering this. ah I think this is a case where perhaps the hype has exceeded where the evidence currently lies. there is a certain extent amongst recreational athletes that you see something that Tadej Pogacar is using or Vanderpool or whoever. And it's like, well, they're using this. I should be doing this because that's what they're doing. ah we are house cats if they are cheetahs, right? We're in the same broader family, but genetically they're a different animal altogether. So, you know, there's a lot of other things that are going on irrespective of, you know, the 30 hour training weeks that they've been doing for decades, that it's probably not the single supplement that they may or may not be consuming that's responsible for performance. So yeah, so that's sort of a, again, a long-winded view of where we sort of sit on ketones at the moment. It's something that I think there's still emerging research on it. There's still some fantastic groups around the world that are working on that and sort of figuring out exactly, is it having an effect? Could it be used for other things? There's other non-athletic contexts where ketones could definitely be a benefit. As I said, it does get utilized by brain and can have some impacts on brain. there may be other contexts that sort of outside of my area of expertise, but for a purely metabolic performance standpoint or adaptation leading to performance standpoint, right now, I would say it's not something that I'd be recommending. If you've ever tried to buy creatine or electrolytes online and wondered, is this actually legit? We got a quick fix. We built a Fullscript dispensary for Nutritional Revolution listeners so you can shop trusted professional grade supplements that ship direct from the manufacturer, no random third party sellers, no sketchy storage. You'll find brands we use with our athletes all the time like Thorne Klean Athlete, Nordic Naturals, Pure Encapsulations, Designs for Health, Designs for Sport, et cetera, and a ton of NSF certified for sport options. Everyone gets 20 % off always, and during promos you can get up to as much as 35 % off, and it's free to create an account. If you set up AutoShip, you'll get an additional 5 % off. Just open up the show notes and tap the full script link to get started. I think, yeah, I definitely appreciate your thorough explanation of that too, of all the different use cases and going through that because I think it is really helpful for listeners to hear. for the post, the study consuming at post, wasn't it? Like a pretty high dose too. It wasn't just like a single bottle that you would get, right? the study that I did, and that should hopefully be getting published in 2026, so hopefully sooner rather than later, that was, yeah, it was quite a high dose. So in this case, the goal for my study was we sort of approached it with, if this is gonna have an effect, we're gonna have to hit it with a sledgehammer. sort of, you don't wanna ever do a study and because you didn't give enough, right? So similar to what we were talking about before with things like sodium citrate, sodium bicarb, you need to have enough in the system to have an effect. There is obviously the caveat that you could go too high and that could have a negative effect. mean, best example of that is caffeine. Anybody that's overdone caffeine knows pretty quickly that they've overdone caffeine. But our logic with this was if it's going to have an effect and that it's going to get into muscle and have an adaptive response and impact metabolism in that sense, we need to have elevated levels and we need to keep it elevated for a period of time. Because if you just take a single one off, potentially what happens is you get a nice robust peak and then within, 90 minutes to three hours potentially that's getting back down to baseline depending on how much you took initially. So what we did in our study was we gave a large dose we gave around 500 mgs per kg body mass as the initial dose immediately post exercise and then we gave them a half dose every hour throughout that exercise period. So at hour one two three and four and we tracked it through to the five hour mark But the other thing we did in our study, again, hopefully this is sort of just wetting the appetite and people will be really keen to read that paper and you can have me on again. But we gave it alongside sort of gold standard sports nutrition guidelines. So we fed these athletes as if they were doing a race. We gave them a high carbohydrate breakfast and then, ah you know, two hours later, got them on the bike. We gave them 60 grams an hour carbohydrate in the forms of gels and drinks. throughout exercise, so fueling as if they were racing. And this was a three hour protocol that was quite difficult. So it was a stochastic protocol moving between sort of 65 and 85 % of VO2 max over the course of three hours. So they were definitely suffering. So if any of my former subjects hear this, thank you very much. They did a fantastic job getting through it. and then post exercise, also gave them standard sports nutrition guidelines. So we refed them post exercise, gave them a protein shake and gave them a meal. because our logic was protein is cheap. It's accessible. You can get batch tested, high quality, you know, approved for use in sport protein for pennies on the dollar. you know, it's really accessible. It's easy to travel with. You can get it just about everywhere in the world. that is sort of your frontline. If I'm exercising and doing a lot of hard, hard work, whether it's in the gym or on the bike, that's sort of, okay, what are we taking post exercise? We want to have protein. We want to have carbohydrate. We want to rebuild, refuel, reload. so it's fine and good to say, ketones had this effect when you've got an athlete that's overnight fast. It hasn't consumed anything during exercise, hasn't had any, you know, protein and, yeah, that might do something, but that's not how athletes live. That's not how athletes train, hopefully, if they're working with good coaches and good practitioners. we wanted to test it in an environment that had high ecological validity. So what are athletes actually doing? Where could this be used? And so we controlled sort of all those variables. But unfortunately, that paper is not covered in the review because it's not out yet. But ah again, there is emerging work that's being done on that, but nothing that would change my perspective on recommendations that I've seen recently. Nice. Okay. Well, I want to be mindful of your time, Jamie. Can I ask you one listener question? em I'm sure maybe you've already seen this as well. I won't say the brand name, but we're getting a lot of questions already coming out about these like broccoli liquid shots. Have you seen those? Yep. And they're kind of like claim on, I think they're like kind of like, yeah. Thoughts? So I haven't tested it myself. I think as I said, at the start of the pod, this is something that keeps me employed. There's no shortage of new supplements and lo and behold, we're at the start of a new Olympic period and suddenly there's a new supplement that's on the front lines. And I think the brand that you're alluding to has said, our goal is that everybody at 2028 is consuming our product. I think that's sort of the tagline. that I saw. Again, I've seen and I've read sort of the handful of papers that exist at present. Again, this is a case where there is, I think this one is most akin to a dietary nitrate, both because it's a plant derived product, but also because it's something that you're taking acutely in order to elicit an effect. With dietary nitrate, you're trying to increase nitric oxide. And that is a potent signaling molecule and can impact a variety of different things. This is the same sort of general idea. m There's some nice cell-based work that there is a sort of possible mechanism of action that this could do something. In terms of how that mechanism aligns from, know, it's a pretty big translation from just looking at a cell-based system. even if it's a mammalian or even a human-based cell, it is still something that exists in a dish. And you pour whatever in there and see what happens. That's an unsophisticated summary of what is actually some very nice work. But getting from that stage all the way out to humans, there's a lot of steps and caveats there. There is some work that has been done. in humans. I think that work is being led by Philip Larsson in Sweden, who coincidentally is one of the people that sort of really drove the dietary nitrate fields for a long time. So yeah, so haven't researched it myself, haven't taken it myself. I've started to get some questions about it myself as well. I would not be surprised if it's something that we look at in our lab in the next little while. We've sort of proposed some ideas around it, but very, very early stages. But ah yeah, I think at this point I'd put a TBD on it. There's been a couple of promising papers. That tends to be how all of these supplements start, is that there's a promising paper to... what will ultimately dictate whether this makes it into whatever the next iteration of the UCI Sports Nutrition Project or any other consensus statement is. Are these replicated by independent labs? ah Because that's the key thing. You need to be able to have more than one person able to generate this finding ah in order for it to be robust. And is it? you know, tested across different scenarios with different populations, you know, just as applied to males and females. Does it apply in different intensities and durations of exercise? ah That's sort of the next step. ah initial sort of reports sound promising. They've definitely got a nice marketing program behind them, which is part and parcel of the gig, ah but we'll see where it lands, you know. Again, it's something that I think it's follow closely. The good thing with something like that or even a dietary nitrate, it may help. It might not, but it's also probably not doing any harm. Again, I don't know the cost of these products off the top of my head. So again, this could be one that could be prohibitive, but if it's not that expensive and it's accessible and you don't mind the taste, Worst case scenario, you're getting an extra serve of veg. ah So, ah but yeah, I guess TBD. Yeah, awesome. That's great. I appreciate that explanation. Where can our listeners find you, follow you? Where in conferences are you speaking at soon? Yep, so I am still active on X to a certain degree, formerly Twitter. I've also got a blue sky, both of those you can find just by Googling my name. I think my handle on both is jwhitfie so W-H-I-T-F-I-E. And then I will be speaking at the European Congress for Sports Science in July of 2026. So I'm doing a session on... on ketone use across different contexts. And so we've got a fantastic panel for that. It's myself, Dr. Brendan Egan, who is a co-author on this review and he's gonna be talking about using it during exercise. I'll be talking about using it after exercise. And then we're also joined by Brianna Stubbs, who's at the Buck Institute ah in the US, is a world championship medalist in rowing, I believe. and did some of the really early work on ketone use and has pivoted towards sort of aging, longevity, and overall health and where ketones could be used there. So I think that's going to be a really, really interesting panel and I'm really excited to be part of that. So I'll be speaking there. And I think that's about it at this point. Australia, unfortunately, is a little isolated. So it's harder for me to get across to some of the big conferences overseas. Yeah. Amazing. Well, this has been fascinating. And for our listeners, definitely dive into the paper because we only touched on three of the many supplements and then talks about dietary supplements and it's definitely worth a read. So we will link that in the show notes for the listeners so they can do a deeper dive as well. But thank you so much again, Jamie, for joining us for a second time. We will be having you back as often as we can have you because you're so... Awesome. And we definitely appreciate your brain, your knowledge, how you can explain, you know, complex topics. is much appreciated for myself included. My pleasure. Anytime. Thanks very much for having me.