Aug. 23, 2021

"Body Composition Methods in Applied Sport Practice" with Prof Graeme Close and Prof Kevin Tipton

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Episode 163 of the Institute of Performance Nutrition's "We Do Science" podcast! In this episode, I (Laurent Bannock) discuss "Body Composition Methods in Applied Sport Practice" with Professor Graeme Close (Liverpool John Moores University, UK) and Professor Kevin Tipton(The Institute of Performance Nutrition, UK).

Discussion Topics Include:

  • Overview of Body Composition and its Importance to Athlete Health and Performance
  • An Overview of Measurement Methodologies That Can Be Used in Applied Sport for the Assessment of Body Composition
  • Practical Considerations When Using DXA and Skinfolds as Measures of BodyComposition in Applied Sport Practice
  • Conclusions and Recommendations for the Field

Podcast Episode Transcript: Download PDF Copy

Key Paper(s) Discussed / Referred to:

Related Podcast Episodes:

Check out our other podcasts, publications, events, and professional education programs for current and aspiring sports nutritionists at and follow our social media outputs via @TheIOPN



We Do Science Podcast
"Body Composition Methods in Applied Sport Practice" with Prof Graeme Close and Prof Kevin Tipton
August 23, 2021



[00:00:00] LB: Hi, and welcome to Episode 163 of the Institute of Performance Nutrition’s We Do Science Podcast. I am Laurent Bannock. Professor Kevin Tipton and myself today, have a really great chat with Professor Graeme Close, all about body composition.


Now, I know I've covered this topic before quite a few times, and there will be a little bit of crossover. Really, the real reason for having this conversation today with Graeme and Kev, was so that we could really delve into issues that we will find ourselves with as practitioners, researchers, when it comes to the actual – the equipment, the kit, the methods, and the assumptions that we take from those methodologies and how we apply them into practice as it relates to body composition generally.


Of course, there are many techniques and methods available to us from super high-tech MRI, the “gold standard DEXA,” which we wrestle with that idea in our discussion, as you will find out, all the way down to the humble skinfold, which perhaps is, rightly, or unrightly, shouldn't be the bad guy, and should be the absolute hero of body composition in the applied setting.


Hence, the recent review by Professor Close and his team on comeback skinfold all is forgiven, a narrative review of the efficacy of common body composition methods. We do use that paper as a really good framework to our chat. We dive in and out, as we do on this podcast of the context, the issues. We unpack the evidence and discuss it from the perspective of applied practice, which as you'll see, does one a different view, a different perspective on some of these techniques, where through the lens of purely a researcher, or a laboratory-based scientists, for example, maybe there are different ways and views of these methods within body composition.


I can't wait for you to hear us talk about these things, where we talk about the various methods, we talk about how they work, how they function, and perhaps, where some of the problems are for applied level practitioners. We do discuss the science, things like, the various direct indirect and doubly indirect methods, the various compartments, but we all talk about it within the context of how these techniques, these gadgets, these methodologies work and how they assess the various aspects of body composition that we're looking to get this data from.


Before you guys get to listen to that conversation, which I know you'll enjoy as much as I did, and I know you'll get a lot out of it, do come check out everything that we do at the Institute of Performance Nutrition. We have recently relocated to Edinburgh from London, so that's one piece of news you may not be aware of. We have all sorts of projects that we're getting into. We have a series of research projects. We have a publication, you'll have heard me and Kev talk about in recent podcasts, that hopefully, is going to come out soon. There's a bunch of other studies that we're getting into, between Kev and I and the team.


Of course, we have our online advanced level diploma program distance learning in performance nutrition, entirely practice focus program. It is very much an advanced program, but it is all about applying the science into practice, not just about the science. Check out our program, should you wish to specialize in sport and exercise nutrition, particularly if you have a background in sport science, exercise science, strength conditioning, our program is perfect for you, as well as nutritionists, of course, who wish to specialize specifically in performance nutrition.


Come check out our program at, where you can also find information about our podcast, all other episodes. You can learn about the team, and of course, our platform for sport and exercise nutrition, so on our new software platform to help practitioners work with their clients, individuals teams. We call it SENPRO, because it's for professional sport exercise nutritionist. You can find all of that information at Let's get to it. Let's get into this conversation about body composition with Professor Graeme Close and Professor Kevin Tipton. Enjoy.




[00:04:42] LB: Right. It's been a while since I have been doing some podcasts, so I’m super excited to bring another episode of the Institute of Performance Nutrition’s We Do Science Podcast. Today, we have two amazing people for us to have a good conversation here with. One of which, of course, is Professor Kevin Tipton, who is our Director of Science and Research at the Institute of Performance Nutrition. I'm particularly excited to welcome back Professor Graeme Close today, who we've had on many episodes over the past.


Of course, there's an extra link here between you guys, isn't there, Graeme and Kev?


[00:05:24] GC: Yes. Because, I've been trying to poach Kev to jump balls, as a visiting professor. Yes. We're now actually, as well as good friends. Well, I hope, we can stay good friends. Kev, we're also colleagues as well.


[00:05:36] KT: Absolutely. Both. I'm very excited to have that link. I think, it's a nice addition to our academic repertoire, if you will, at the institute to be linked with such a prestigious program, as you guys do.


[00:05:50] LB: For me, it comes back, like to the very first podcast we did, which is, dare I say it, Graeme, was a very long time ago. It was like, five, six, seven years ago, something like that. Now anyway, that was with yourself and James Morton, of course. I think, the first paper that I got involved with that was published was that case study that we all did with you guys as a collaboration with OJMU.


We like to feel that at the IOPN, we’re like the Switzerland, so to speak of what we're doing in our field, but we do have a close link with you guys for good reason. Because OJMU, you're great at what you do, particularly with sport and exercise nutrition. I guess, while we're quickly talking about it, Graeme, because not everyone is necessarily familiar with yourself. For you guys, this might be the very first podcast that they've jumped on to, and since it's been a little bit of a while since I last put out a podcast, I got a bunch coming up, of course. Maybe you guys could just give a quick bit of background about yourself, starting with yourself, Graeme.


[00:06:54] GC: Yeah. I'm currently a Professor of Human Physiology at Liverpool John Moores University, where I've been – I did my undergraduate degree at Liverpool John Moores back in 1996. I had a brief – exactly, yes. I had a brief sabbatical, seven years sabbatical at the University of Liverpool, where I was brushing up on some of my basic molecular biology skills in the area of free radicals.


I'm back at John Moores now. Perhaps, of more interest to a lot of our listeners, is the second part of my life, where I'm currently the Head of Nutrition for England Rugby, Head of the Sport Nutrition Program for the European Tour Golf and Ryder Cup teams. I consult with a variety of other organizations. Actually, I'm consulting with Aston Villa, which I believe Kevin will be happy, but I'm sure I remember, Kevin was an Aston Villa fan. That's one of my consultancies for this year as well.


[00:07:48] LB: Villa. That's awesome. Kev, come on, tell us, if they don't know who you are, because you should be very familiar to our guest now, but let's just have a quick overview.


[00:07:57] KT: As you say, now thanks to you, the director of science research for the Institute of Performance Nutrition, I’m very happy. Thanks to Graeme, I'm also a visiting professor at Liverpool John Moores University. To make it clear to people, I don't get paid anything to do that. People often say, “Gosh, you must be raking it in.” No. It's simply the honor of being involved is why I've done that.


You said ’96, and I'm going, “Uh-oh. I'm a lot older than that.” Yeah, I've been doing this a long time. I started my career, I would say in Florida, but mostly, became known for working with Bob Wolf in Galveston, Texas. That was such a privilege to learn from a man who, despite the fact that I'm talking to two of the sharpest people I've ever met, you can't touch Bob Wolf’s brain. He's amazing. I was lucky. I've always said, it's better to be lucky than good. That was my career in a nutshell.


[00:09:02] LB: You guys are just incredible in terms of your contributions and overall impact to sport and exercise science and sport and exercise nutrition. I'm feeling humble sitting here with you. I can honestly say, actually, both of you have equally had the most profound impact on me in my career, and I've done pretty well of late. I'd to thank you both for your involvement in shaping me over the years. Although, Graeme, you're the baby of the group here, so to speak. You are the baby here. I'm not even talking about how old I am.


Right. Okay, let's get into it. The reason why I have assembled this group here to have this conversation is because, Graeme, your group recently published another really, really useful review on comeback skin folds, all is forgiven. Of course, it was your narrative review of the efficacy of common body composition methods in applied sports practice. We're absolutely going to talk about that paper. We're also going to come at this from the perspective that we're obsessed of that in the OIPN. You, of course, Graeme, hence, relatively recent podcasts that we've done on your paper to podium, paper and lectures you've done for us at the IOPN, of course.


Of course, we're, and our whole thing is about bridging this gap between science and practice. The purpose of this conversation today is not just to talk about the various methods of body composition, the science, if you like. What we're really interested in is how should that influence practice? Off microphone just a minute ago, we were talking about food first, and how perhaps, that term has become oversimplified. I understand there might be a paper coming up that's related to that, Graeme.


My bugbear is this concept of evidence-based practice that word, and, “Oh, I'm evidence-based,” or whatever. I like the idea of being evidence-informed. Because as a practitioner, you've got a lot to consider, not just the science or the evidence. There's all sorts of crazy stuff that goes on in “the real world,” to include individual needs and preferences and financial considerations. Is it even remotely practical under the circumstances and all that stuff? That's why I really like this paper, this review, because as sport and exercise nutritionists, body composition is absolutely something that we're involved with.


It's one of those things that if you were to differentiate a clinical nutritionist from a performance nutritionist, or sports nutritionist, body composition, as opposed to just weight performance, as opposed to just health is something that we're very much into. As Kevin, I know, because of the various conversations we've been having with our students on our journal club, recent lectures, and of course, the various contributions you've provided us with, Graeme, we need to be much more critical in our evaluation of the information and tools and resources, and so on, that we're going to use to make the decisions that we make and the recommendations we're ultimately going to give.


Anyway, let me just bring this back to you, Graeme. Why did you feel the need to put this review out, you and your colleagues, for the paper? Given, there's quite a lot of work out there on body composition. There have been reviews. I've done numerous podcasts on this topic, but I have a feeling this one's going to be particularly interesting. Graeme, tell us.


[00:12:35] GC: I guess, it comes from what you were saying about in my introduction, but I didn't have a foot in both camps. As you say, whenever you work as a sport nutritionist, you will perform some body composition assessments at some point. Without doubt, you will. Despite it being probably the most common tool for a sport nutritionist, it's amazing that there's still no gold standard technique. You hear people talk about things, like DEXA as the gold standard. Then when you're trying to find where that's come from, that's just one of these nebulous terms that people just decide, we'll call it something, a gold standard.


What I was finding a lot is when you work in elite sports teams, almost reuse of skinfolds was put to bed about five or 10 years ago, because it wasn't seen as sexy enough. We had all these machines that actually give percentages and they give nice, little pretty pictures. When you actually come to look at it, what I was finding is the amount of controls you needed to put on things to use them type of equipment, that we would use nicely in a controlled laboratory environment.


In the actual real world of applied practice, I was beginning to realize that we weren't able to put them controls on it, and we can touch on them later, what these controls are. Because of that, I'd found in my own practice, I'd gone back to using the humble skinfold caliper. Actually, finding, but I was probably getting more meaningful and more beneficial data. I was often having a conversation with directors of performance of why are we not doing anything that seemed more novel and more sexy than a skinfold caliper?


I just felt that it was about time to write a review paper that really looked at body composition assessment from the eyes of the practitioner, rather than from the eyes of the research scientist. I think, they’re two very different things.


[00:14:34] LB: Graeme, that final bit of what you just said, I think, is particularly important for people to be bearing in mind as we expand this conversation today. Because I've talked about the importance of context, as we all know. In fact, to the extent that you guys and some of your lectures have even put bubbles of the word context in a picture of me as a joke.


I don't apologize for that, because context is important. Actually, my new buzzword, Graeme, is relevant. Is it relevant? You're sitting there making these decisions as a practitioner, and you've got all sorts of things that influence the choices that you make, including, another word you just used, Graeme, is sexiness. Particularly, in elite pro football, for example. Something I'm now working a lot. It's particularly interesting how the perception of what we're doing by the athlete, by the client, by the person that we're directly trying to impact is something that is an important factor, I feel, Graeme, where we're going to talk in a minute about different types of body composition methodologies, which involves some pretty sexy gadgets and toys.


Of course, the humble skinfold caliper, by perception to the athlete has an unfair image, if you like, to the client. Or maybe it does, or maybe it doesn't. Graeme, what are your thoughts on that, just briefly, about the perception of the gadgetry and the assumption of its accuracy and importance? Bearing in mind that the impact that that has in what we're trying to get our clients to do, which effectively is behavior change. As a tool, maybe some of those gadgets and their impact on behavior change has something that's worth considering. What are your thoughts on that?


[00:16:22] GC: People always want the next best thing. If something is tried and tested and excellent, there almost seems a, “Well, yeah. We know about that. What else is there?” An example I use this all the time is creating. For me, creating is still the best supplement we probably have over from a sports performance. Yeah. It shocked me how many sports teams aren't using it, because we've known about it for 20 years. We want the next best thing to creating.


Actually, there isn't anything. That's just one example. I think that's the same with the humble skinfold caliper. We've been doing it for absolutely years. Then all these new things come along, where we give a lot more detail. I'm doing “detail,” because when you actually look at where this detail comes from, a lot of this detail is guesswork. Because it's in a printout, and it looks pretty, then what you're getting is people buy into it. I've seen this recently with some of your [inaudible 00:17:14] technology, where you can ultrasound somebody which is basically a set of skinfold calipers that then dissolve a guesswork and puts it in a nice, pretty colorful picture.


People think that that's now – well, that's measuring this, where actually, it's guessing it based on the same assumptions as skinfold calipers. You are right, that you put somebody on a DEXA scanner, and you show them the picture of where their body fat is often that can have a more profound effect on behavior change and taking a few measurements. I guess, it comes to the relationship you have with the clients, and that level of honesty and that level of trust, where actually, they understand why we're doing it.


The other about it is because of the speed of it, and the cost and the fact that it doesn't involve ionizing radiation, we can do it on a every second week, which I do think, has certainly had effect in my hand on behavior change, when we know that was a measure come in every two or three weeks.


[00:18:17] LB: Yeah. This is not an either or scenario, is it? These are all tools in a toolbox. Actually, you might be using multiple tools at the same time. For example, beginning and end of season decks, and then skinfolds throughout the season, and so on. We'll get into that. Kev, we talk a lot to our students about critical thinking and your thing of being skeptical and open minded that you're really driving through to our students, but this concept of belief, particularly in in science and accuracy and stuff like that. What are your thoughts to share on that?


[00:18:50] KT: What occurred to me as I was listening is that it's certainly true that a lot of coaches, athletes, and even practitioners are going to assume that because it's got fancy bells and whistles that a method is better. As Graeme described quite nicely, it's not necessarily true. I mean, the algorithms that DEXA uses, most DEXA manufacturers will not reveal their algorithms. They're just making it up.


We talked about in the lecture yesterday, you got to think about what you're actually measuring. What are you measuring with DEXA? What are you measuring with skinfolds? Then, decide how to utilize that information. I think, a lot of people just take it for granted. That, because DEXA says there's this much body fat, that there's this much body fat. That's not necessarily true when you look at the details of what is actually being measured there.


[00:19:46] LB: Yeah. We're going to unravel these things as it relates to the main methods that practitioners and scientists, researchers and so on, we use them as the review does. Graeme, you've given us some great insight into each method, and from an applied perspective, you've helped provide a framework that I think is yet, another useful resource for practitioners to have at their hands to make the right decisions at the right time.


Graeme, referring to body composition, I think, the listeners know what we mean by the term body composition. Why is it so important for us as applied sport and exercise nutritionist to be obsessed, if you like, with body composition? Why do we even need to test it anyway, Graeme?


[00:20:29] GC: That's a pretty better question than you actually think it is, to be honest, Laurent, because in some sports, I don't know if we do. You’re right. I have become obsessed with it. In other sports, it's a key component of performance. We only need to think about sports, such as cycling, which involves transporting a mass, i.e. your mass on the object. The more of that mass, the more wattage is needed to actually move that, so the harder it will be. We've seen remarkable changes in the physique of cyclists, maybe over the last decade, has become more of a realization.


Likewise, in the sports where I work, such as rugby, we know that mass is important. Let's go back to simple biomechanics. Force is mass times acceleration. If we want to import more force into contact, we're going to need more muscle, more acceleration. Ideally, that mass will be lean mass, because that will allow us to transport it more efficiently for 18 minutes in a rugby game. Rather than just, there's a reason why sumo wrestlers can't do an 18-minute rugby game, because we also need that aerobic component.


An understanding of body composition, I think, is really important for performance. I also think it's important for health as well. We can focus on some sports, where we know that – I know you've covered it on previous podcasts, the relative energy deficiency in sport, reds, and we can begin to track people becoming too lean. I think, that's just as important as people over. I think, it's an important tool in our toolbox, as you talk about. I also do think it's been over-emphasized in some sports a little bit.


I've seen loads of examples in my sport of rugby, where some of the best players in the team, the ones we've got the worst body composition. Likewise, some of the best plays, we've got best body composition. It's a very individualized thing. I would say, it's important to measure. I would just argue that we shouldn't become obsessed with it.


[00:22:33] LB: Yeah. Like we're saying, it's a tool in the toolbox. Although, all nutritionists, performance nutritionist clearly should have an understanding, but also, a competency in the ability to choose the right tools and the strengths and limitations of that, which is something that I want to get into in a lot more detail in a minute.


Kev, Graeme used the word gold standard in this review, and everywhere on this topic, we hear terms like, criterion methods, and so on. Where do you think the gap lies on between, well, science and practice, particularly as it relates to the information that we're reading in laboratory research studies, they're using these techniques that derive information that we as practitioners use to inform our practice? Is there anything there? I mean, and I'm thinking very much about your lecture yesterday, of course. What are your thoughts on that?


[00:23:28] KT: The general principle is what we always try to emphasize, which is, every method that you're going to use has strengths and limitations. It's important for the practitioner to understand those strengths and limitations, so that they can utilize that method effectively. If you compare DEXA to skinfolds, as Graeme said, not everybody can go and get a DEXA. You have to go to a certain place, a lab, or a hospital that has the DEXA to do it. Whereas in the skinfolds, you can do it out in the field.


As long as you understand the limitations of those measurements, then they're just as valuable, if done properly, of course, which we're going to assume everybody's going to do, which I'm not sure is a safe assumption. If you're old enough, or young enough for whatever to remember, when I was training, underwater weighing was the gold standard.


There were problems with that. You had to understand what those problems were, in order to effectively interpret that. I think, Graeme touched on this earlier, which is I remember having tons of trouble with coaches about how important those measurements were. In many cases, they would take that as, as you say, gold standard, and you go, “Hang on. Hang on. We got to interpret this a little bit.”


[00:24:45] LB: That is why we're having this conversation and we're recording it for the benefit of our listeners and students and our colleagues, practitioners and researchers out there. I don't mean for what I'm about to say, to come across in any particularly, accusatory, or negative, or insulting way, or whatever, but there are a lot of people, which I would include myself very much in the past, was ignorant of these issues, these limitations. Some people are very – they’re ignorant of their own ignorance on this topic, so they're just happily using these technologies, because of the perception of the accuracy.


I'm thinking, there's all these functional tests that exist, particularly in the nutrition industry, that you've got blood, urine, saliva, stool testing, and so on. Goes off to a fancy lab and comes back with these fancy printouts that, as you say, Graeme, and of course, there's an assumption there, not just by the patient, the client, the athlete, but the practitioner themselves are not actually aware of how misleading that information is.


Part of that is because of lack of the appropriate education in this, which is missing, because it's very much a commercially guided product orientated area, isn't it, Graham and we have this issue of supplements, of course, but maybe people don't realize, that exists with testing, gadgets, machines, that counts for a lot of money also out there in the industry.


[00:26:15] GC: Yeah. One of the hardest parts of this paper was figure two. I can talk about figure two, because it's an open access paper, if anyone wants to go on –


[00:26:24] LB: I’ll link to it. Yeah.


[00:26:25] GC: Thank you. Yeah. Figure two at the end, we tried to put together a flow diagram, whereby in different situations, each different tool could be the best choice for you to arrive and say, “This is what we believe is a gold standard.” What is the best in a specific scenario? In some situations, we came to a conclusion, with an accurate measurement of bodyweight would be the best in that situation with the tool that you've got available to you.


Now, when we say there's no gold standard, I guess, technically have a race, which is cadaveric dissections. Now, I've managed to convince coaches to let me take muscle biopsies. I'm not convinced, I would let them kill a player, so I could cut them up and analyze a body fat on the cadaver. We've got to remember that everything is related back to that cadaveric dissection. Where Kevin talked about hydrostatic weighing, and again, what's your criteria and measure it's related back to?


Yeah. I think, it's important point, but I'm not dismissing any of these techniques. What we're saying is that the practitioner needs to be aware of the limitations and the constraints of that particular technique, and then use an informed decision based on what they want to achieve from it. For example, if we wanted to measure bone mineral content, well, we've no option, we've got to use DEXA. Likewise, if we want some limb-specific measurements, again, we've not really got an option.


If what we want is something much more simpler, we want to track changes in body fat over a period of time, well, then actually, we might set that a skinfold is the ideal one at that point. If you want an idea of total body water, we might do with some of the fighters that we're working with. Well then, the bioelectrical impedance comes into it. They've all got their own usefulness.


What I don't think practitioners do enough, is ask themselves, in this specific situation with the constraints I have with this client, what is now the preferred methodology? Hopefully, that's what figure two in this table can help with.


[00:28:37] LB: Absolutely. Yeah. That's why I've become obsessed with asking myself in my own practice, is this actually relevant? What is the relative value of this? Or, a phrase I used to use a lot, which is you can, but should you? Speaking of figures, in figure one, you visually display very well a number of things, I just want to quickly get into, which is the various compartments, because of course, when we're assessing body composition, there are different methods, of course, and you also discuss the difference between direct, indirect and doubly indirect. Why is this important? What are the main considerations, you think?


[00:29:18] GC: Yeah. I think again, it's really important to then think about what do you want to actually measure. For example, skinfolds is classed as a two-compartment model, which is simply fat-free mass and fat mass, with the assumption that if you measure one, you can predict the other. If that's all we're interested in, then that's where the skinfolds can be quite useful. We move on into DEXA, which is a three-compartment model, where now we're able to add bone mineral content into this as well. If you're interested in bone mineral content, then that becomes important.


Note, as far as I'm aware of, there’s no single technique that can be a four-compartment model, but what you can begin to do now is integrate techniques. With a four-compartment model, we can also know begin to look at total body water as well. By combining DEXA with bioelectrical impedance, we can now get a much fuller picture of this separation. Now, it is important to remember that when we're talking about dividing the body into the different compartments, this is conceptual, rather than anatomical. This is a great anatomical way of doing it. It just helps us to understand that body that little bit more.


You asked me about direct, indirect and doubly indirect. Well, direct takes us back to our cadaver. The only direct way to measure this is cadaveric dissection. As I said, not convinced would convince a coach into letting us do that, but particularly football players. I think, they're very much valued, because so much people pay for these people. Not going to go down the direct measure.


Then, we get the indirect methods. This includes things like the hydrostatic way in air displacement, plethysmography, which is hard for a beginner to say, but we did all right, thought. Things that bond parties are ones that we've heard. Ultrasound and things like that. This is where we're looking at this relationship between an estimation of body fat, but we're not going into a doubly direct method, where we then add a regression equation on top of it.


This is where skinfolds, I think, gets a lot of bad press. Skinfold thickness can be an indirect method, where that's the current ISAK suggestion, so the International Society for the Advancement of Kinanthropometry, whereby you leave it as an indirect method by reporting it as a sum of eight mill sites. We do skinfolds in eight different sites, add it up, you have 50 mils.


The problem then, is when we look at these doubly indirect ones, where we put a regression equation number, and I think was hundreds of these equations now. We showed in this paper, you can take the exact same skinfold sites, and you can come up with somebody as a 4% body fat, or a 15% body fat, which is remarkably different. That's where the problem comes when we start using these equations, because these equations try and come up with what would that be in a specific population.


They're really hard to be generic. There's a good one, but Tom Reilly developed for football based on DEXA scans. That's because in football, you've got quite a narrow bandwidth, you don't have real range of body compositions. Wherein rugby, I can tell you now for sure, there is no prediction equation that is suitable. There is nothing that I can use in a prop forward who maybe has a 150 mils, that's also suitable for a winger as maybe 37 mils.


Then, I've got to decide, at what point do I switch from an equation that might be good for a winger to one but might be good for a prop? I also have some wingers are up a 100 mils. The point being with that is the best advice at the moment is just to report as some of the mils and take all that guesswork out of it. Then, if what we're interested in tracking change over time, if somebody has come down from 80 mils to 70 mils, they’re moving in the right direction.


[00:33:24] LB: Yeah. I'm looking forward to delving back into some of those areas when we talk about each of the main specific methods. Of course, what we're talking about a lot is the assessment of, we say body composition, but we focus particularly on body fat skin folds and so on.


Kev, from the perspective of yourself as a scientist, who's been working for a very long time and has had a huge amount of impact on –


[00:33:51] KT: Hey, easy.


[00:33:52] LB: Hey, yeyey. The knowledge that we have on muscle, muscle protein synthesis, hypertrophy, that sort of thing. From a measurement perspective, what are your thoughts in-line with how Graeme has just been discussing the particularly, body fat?


[00:34:10] KT: If you're talking about studies and actually measuring it, muscle mass, for example, it probably depends on your ability to get the funding to do certain measurements, versus others. If you can do muscle biopsies, you can you can measure muscle cross-sectional area. You can actually measure the fiber’s size. If you can do MRI, you can actually get a reasonable estimation of muscle volume. That's a far cry from where a practitioner in the field is going to be. That's why, this paper, I think, is so important. Because as we've said several times now, people get focused on these bells and whistles. I can put you in a magnet and get your leg volume, but how many people can you do in any particular amount of time and how much does it cost, and you got to get them there.


It's not a realistic way to think about things. I really liked what Graeme was saying earlier about the value of the information in various – in his example, rugby players, that just tells you, even within the same sport, you can have this huge variation. That doesn't even give you the example of a 17-year-old female gymnast trying to get a gold medal, versus a 30-year-old prop forward, and you're using the same equations as he said, with that regression that you use.


All those regressions, by the way, and Graeme hinted at this, but those are all based on cadaver studies. I used to always tell my students, “Yeah, if you really want to get someone's body composition, let's put them in a blender.”


[00:35:46] LB: You guys are going to get a reputation here. People are still crossing the street.


[00:35:52] KT: What were those two guys back in the early 1800s, some in Edinburgh that would steal cadavers and sell them to med school? There's a film based on it. I can't remember now. Anyway, Graeme and I are going to be sneaking around and –


[00:36:05] LB: Well, we're obviously bringing it since Edinburgh is my hometown. This is going to be a new reputation. Graeme, where I'm trying to go with this is obviously, is to help people understand the strengths and limitations of these methods and give them the information they need to have the right kinds of impact on their athletes, their teams, their clients, and so on. It's not just about how fancy the method is, or the equipment, or whatever. There are issues that are also going to be a factor here, which of course, we'll unpack on each method in a minute in more detail.


We need to consider things, like test, retest, the reliability of that process, the repeatability and so on, because the assessment is more interesting in terms of how it influences practice when you do multiples of these tests, Graeme. What are your thoughts about that?


[00:36:59] GC: Again, that will help with the figure two that I talked about, because one of the considerations in that is the experience of the tester. We know that skinfolds are particularly effective in a highly experienced ISAK-accredited tester. They're actually pretty poor, if you've got cheap calipers, cheap plastic calipers that stretch, or non-calibrated calipers. We get our calipers calibrated once a year at John Moores. I wonder how many uncalibrated calipers are out there.


Also, in untrained individuals. I see people that are just guessing where the sights are. We know that as little as a centimeter difference, particularly on a tricep measurement, can be a huge difference. I remember when I was being taught statistics and people talking about reliability. I think, about in Greg Atkinson, who's one of the best sports statisticians I've worked with. The example he used to always use is, can a Ferrari get around Silverstone in two and a half minutes? Well, depends who's driving it. Either crashed it, the first bend, doesn't mean that's not a reliable piece of equipment. It's just the person driving it isn't reliable. That's a really important point that you touched on.


Then, there’s a nice paper about this new method of ultrasound scanning, which we can touch on later, if you want, which doesn't appear to be as good in my opinion, as skinfolds, unless you're not experienced with skinfold calipers. Then, if you've not got anyone qualified within a team in skinfolds, well then, that might be more reliable, because it's less sensitive to the technical challenges of using calipers. Then it's the same when you talk about, and I'm sure we're going to in DEXA in a bit more detail.


The reason I moved away from DEXA was a growing appreciation of the amount of things that have to be controlled to get reliable data, which in a laboratory setting is pretty easy. I can get people in at the same time of day, after following the same diet for two days, the same hydration, fasted, everything like that, not a problem.


You work in an elite sport environment, and you try and set the gaffer that I would like all them things controlled so I can get an accurate measure. You have no chance of control and all that. We showed, and I mentioned it in the paper, I think at one point, but it's an extreme example, but we had somebody making weight for a fight, who came in on two consecutive days. It was something like 10 kilograms of difference in lean mass in 24 hours. Now, we know that that is impossible to lose 10 kilograms of lean mass in 24 hours. It just shows that if you're severely dehydrated and glycogen depleted and everything else like that, the profound effect it will have on your data. When we think about the way athletes, now carbohydrate periodize and the different things they do on a daily basis, and whether they're on creatine at that point or not. I just think the chance of getting meaningful long-term data in DEXA becomes quite limited.


[00:40:02] KT: BIA is the same thing in pedes, is probably even more sensitive to hydration than DEXA. Also, one thing that we haven't spoken about is we spoken about the skill of the of the individual they need to be trained and in the technique. Often, if different people are doing the measurement, you get completely different. In fact, I used to do that when I would teach body composition labs, is I would have three different people do the same measurements, and then we'd step back and look at it. It can be incredibly variable.


You need the same person to repeatedly do the same measurement. That's especially for skinfolds, but also for BIA and DEXA, and all these other things. It's incredibly important to be rigid with your techniques.


[00:40:51] LB: Yeah, absolutely.


[00:40:52] GC: This was another motivation for writing this thing, was the make of a machine is important to whatever you're using. Not only the same person, the same actual machine. We know there's three or four different main manufacturers of DEXA. It's important that if you compare and you compare with the same machine. What I hadn't realized was we got a new machine about four years ago now. We asked for it, because it was in the middle of some long-term studies, and our machine had come to the end of its life. It couldn't get serviced anymore.


The same machine, but just the upgraded model. Everything was as similar as we could get. We were then picking up about a 2-kilogram difference in lean mass. We are a group of athletes who were tested. Then about two weeks later, the test was out, we got them back into testing machine. The same people, same conditions. We will find that those consistently 2 kilograms less lean muscle mass, which obviously, caused a major issue, because suddenly, now as a percentage body fat were reporting that mean percentage body fat had gone from 18 and a half to nearly 22.


The club were like, “What's going on here?” You're like, “You've not all done that in a two, or three-week period.” Not only does the machine need to be the same, the software needs to be the same. Then, another thing we found playing with our machines is, there's hundreds of difference equations within that DEXA. You can pick which equation you want to use, and people don't realize, but ultimately, also with a DEXA scan, unlike any of the other ones that get you as a percent, the end stage is using one of these validated prediction equations.


By changing that prediction equation within the DEXA, again, you can change someone's body fat from high 20s, to 15s, for example. Also, you said the skill of the operator. You need to segment the body on DEXA. By, where you put them lines can make a world of a difference. Should I tell this story? Maybe. I'll say it with protection. Scanned player came out at 10.1% potentially. This may or may not have happened.


In a certain team at 10.1%, it's a massive fine. That 9.9% it's you're absolutely fine, which is the ridiculousness of elite sport. We all know that that's nothing. That we’re going to get an error of the machine. Yeah, ludicrous. Yeah. Just by when you put him in lines, and if you wish to move that line half a degree left or right, that could drop it from 10.1 to 9.9. No one knows exactly where that line should be to that degree of accuracy. You can make your mind up, whether that play went back with a 9.9, or a 10.1 report, but it makes absolutely no difference. It's been ludicrously of what still goes on in professional sport.


[00:43:43] KT: Maybe that's how we can make our millions by doing body composition assessments with athletes and letting them pay us to get the right number.


[00:43:51] GC: You know what? I'm sure that has gone on in the past. I can say categorically, that has never happened with me. Yeah, you don't know the small errors. That's what people need to remember as well that each machine has got a coefficient of variation. We know that it would need to be outside of that, for it to be a meaningful change. That's another thing that I don't think people think about. I've talked about this a lot with skinfold measurements, that if someone’s at 82 mils one week and 84 the week after, I don't think we've put on 2 mils. That is certainly within the error.


There's possibly an argument for reporting in multiples of five, but who knows to actually, as much as anything to stop coaches getting overexcited, or over disappointed when there's a one or two mil move either way. Yes, absolutely right. We need to have an appreciation of the error associated with every single piece of kit from skinfolds, all the way through to DEXAs.


[00:44:52] KT: Whenever I used to talk to people and they would tell me that they detected a change of point one, or in any value that let's say, body fat, for example. If they said, “Yeah, my athlete went from 10.2 to 10.4,” I'm saying, either you do not understand the limitations of the method that you're doing, or you're trying to oversell what you can do. Because you could do that a 100 times and you're going to get that variability for trying to repeat body fat percentage, especially. Because as you said earlier, you have all these levels. You got the regressions that you got to use. You got to decide which equation to use, and it's the same thing as you mentioned earlier about the DEXAs.


Practitioners, if we're going to bring it back to what they should be thinking about I,s to not try to oversell what they're doing, and to understand that they don't have that precision in these measurements.


[00:45:48] LB: Well, that's where this concept, which is a whole another podcast in itself, there's ignorance, and then there's willful ignorance, isn't there? That's where I was mentioning earlier is there's some areas, I think, that are unfortunate in the field, where there is an endpoint where somebody might be selling supplements, or they're selling tests, or whatever. Ultimately, we're bringing this back to this concept of trust. Can we trust the information enough to make the kinds of recommendations that our athletes need to do? It's very high stakes, isn't it, Graeme, where, yeah, might be a football team, and the impact that those decisions can have on those players, those rugby players, football players.


Then, you're talking tournament's that might – like the Olympics we've just had, for example. These decisions can have very long-ranging impact that can be amazing, or they can be disastrous. Listen, let's just refocus this applied aspect here. Look at a few of these – the main ones. We have talked about a few of these, like skinfolds, and DEXA. I just wanted to just quickly come back to a few. Graeme, you could help us get to understand a little bit more about each method and what we should take from it, given the limitations we have on time. We want people to read this review and some other resources, I'll point them to in the show notes. Hydro densitometry, you referred to underwater weighing, and so on. What do we need to know about that and take away from it?


[00:47:12] GC: Yeah. It's a two-compartmental method. If we want to come up with a percentage, again, it's doubly indirect, so it's got the issues of that, the issue with Hydro-densitometry is the things you need to put in place to get accurate data. There's so many considerations of what you need to do. We need to, first of all, it can be quite uncomfortable for people, because they needs to be weighed underwater in minimal clothing, with all exhale from the lungs. You're holding your breath after an exhalation under water. It can be expensive. It's time consuming. I don't think with the modern techniques that are available, that there's real – apart from potentially in research studies, I don't really see any place for that anymore in the type of context we're talking about of elite sport, doing well, with highly qualified and highly skilled individuals. It's great.

[00:48:08] KT: You hinted at this, that the individual who's being measured can make a huge difference in how the measurement goes, because you can make assumptions about lung volume. Mostly as Graeme said, you've got to expel all the air. Nobody is ever comfortable doing that.


[00:48:25] GC: Not then going underwater and maybe holding their breath for a few seconds. It can be quite claustrophobic. You can feel really uncomfortable. Yeah, skill in the measurer and skill in the participant. Yes.


[00:48:40] KT: Unlike skinfolds, mostly the participant, or the person you're measuring just has to stand there and allow you to pinch them, which can be uncomfortable and unpleasant for some people, but it's nowhere near, as you said, going underwater, expelling all the air in your lungs and going under water. Then you've got to sit there and depending on the precision of the scale.


I mean, I don't know about you, but I remember scales just waving back and forth, and you're just trying to guess where the where the point is, because the person was so uncomfortable, they're making everything shake. It’s both. I agree with you completely that I think in modern times, I would absolutely recommend what you're saying in the title of your paper here, which is, hey, why not skinfolds instead of this? In a practical standing.


[00:49:28] GC: In a practical one, correct.


[00:49:30] LB: The concept of underwater weighing is not – I mean, we don't see it anyway. It doesn't in an applied setting, it's not something we're going to see. Something we do see, of course, is air displacement plethysmography. You've mentioned BOD POD as being the most common method. What about that one? Because we do see that. I've seen in the States, for example. We see a lot of BOD PODs exist over there. What are your thoughts on that?


[00:49:51] GC: It's a similar principle, isn't it? Rather than water being used to estimate body density, now we're using air to do it. It's a similar type of technique, where you sat in the chamber, you have minimal clothing, swim cap type thing. We're using air now to measure that, instead of water. I think, it's pretty more practical than, let's say, hydro densitometry. It's an easier one. It's a lot more affordable. It's a lot easier to standardize.

The research would tend to suggest that the ability to pick up subtle changes in athletic body composition that we may be interested in, as may be lacking. If you was doing a study on weight management, and you was looking for quite large changes, 5, 6, 7 kilos over a period of time or whatever, in a research setting, I think was some merit and miss. Again, it's more time consuming than skinfolds, or something like that. I don't think, my reading of the literature is, it's going to give us that degree of sensitivity that we perhaps, would like in our replied setting. Kevin, have you done much with BOD PODs over time?


[00:51:00] KT: We never had one. In my experience, we had underwater weighing, the hydro densitometry. Then we went to DEXA, with skinfolds scattered in between, in my experience. I agree with you. I don't see any of my reading, I can't see why. I mean, I guess it's like you say, it might be more practical, especially in a lab setting, because you don't have to have – I mean, we were doing underwater weighing. We had an old cattle tank that we bought from a farm and put into a lab, and that's what we're doing.


Other people I've seen did it in swimming pools. It's a lot more fuzzy than just to have your little BOD POD in the corner in the lab. I would say, between those two, you could make an argument for practical that the BOD POD might be preferable. Other than that, it's Archimedes principle in it. I mean, both of them were based on that.


[00:51:50] GC: Correct.


[00:51:51] LB: If we move this over to something that is prolific as a testing method, and system, it's a bit of kit that actually, we will find in potentially, millions of people's houses. You've got these scales that you can stand on in your bathroom, and it will tell you not just your weight nowadays, but also, what your body fat and water content, and so on. Of course, what I'm talking about there is this technology, this method, BIA, bioelectrical impedance analysis, and/or all the way up to some really quite expensive kit, which is the spectroscopy method, the bioelectrical impedance spectroscopy, which potentially is more interesting. I mean, give us some background on that and what your thoughts are as it relates to applied practice, in particular, since it is very accessible.


[00:52:38] GC: The benefit of this one is exactly what you said, Laurent, is it's very accessible, and it takes very minimal training from either the user, or the tester. Maybe I should caveat that. It takes very minimal training to generate a number. It takes a lot more training to generate an accurate number. If you're in a gym, you can stand on one of these machines, and you can get a number with very little training.


Important to differentiate as you just said then, Laurent, between BIA, which is bioelectrical impedance analysis, and BIS, bioelectrical impedance spectroscopy, people confuse the two. Often, what they will cite is the literature on the more accurate method, the best to justify the BIA. BIA is basically, hand-to-hand and there can be these handheld machines that you see people holding. BIS is generally, you take your shoes off, and it's passing the electrical current through the body.


The idea being, is a low current pass through body, will pass through different tissues at different speeds. It will pass through fat-free mass much faster than fat mass, because of the water content. Then based on a series of doubly indirect measures, you can get a percentage body fat.


One of the key things, and Kev touched on it early on, and I just said it then, because of the more water content and the fat passes through it differently. Well, then water content of the human body makes a huge difference. Your hydration state can have a massive effect on when you do it. That's why I said at the beginning, to get good data is easy. To get good, accurate data might involve the researcher putting a few conditions in place to make sure that we're in a decent state. We use BIS in our department for measuring total body water from our boxers, our jockeys and things like that. We're beginning to use it to put it into a four-compartment model to do it.


I think, as a standalone method in athletes, it's probably got limited value, because of the issues with hydration and things like that, and how well we can control it. I think in a general healthcare setting, in the wider population, again, if we're looking at gross changes, and we want a decent measure before you do a six-month intervention, and you want to see is there a big change? Well, then meant subtleties of the difference in the hydration may be less important. If we're trying to track acute changes in athletes, I think we need to have a little bit of caution. If we are going to use it, promote the more expensive, unfortunately, bioelectrical impedance spectroscopy over, but much cheaper handheld devices.


[00:55:26] KT: You're probably both more qualified than I am to say this, but because of the standards that you have to put into this measurement. For example, if I were going to measure your body composition, Graeme, if you go and take a pee or not, it's going to change, because of what you just said, because of the way it's measured, the passing through the electrical current, or if you've had a meal. Really, if you want to do all these things, you need to standardize. You got to do it in the morning, you got to make sure that they have the same toilet status.


We used to always have them, just everybody would drink 500 mils of water ahead of time, just to make sure that they were in the same hydration state. To do this in athletes, I'm only imagining and you can tell me if I'm wrong, but it seems to me that that's almost ridiculous to even think that you could get away with a whole group of athletes. Don't need some of that rigor, you can just do it with these people.


I think, these are the kinds of considerations that practitioners have to think about is it's like, sure, if we're going to do this in the lab, as you said earlier, we bring them in the lab, and we can do all those things. You can't really do that out in the field.


[00:56:37] GC: Yeah. I don’t think, if you didn’t get the coefficient of variation, then. The CV will be much wider, if you don't do all that. If you want to know is somebody in a healthcare setting has dropped two stone over a 12-month period, and that that two-stone is from body fat, then it might be quite useful. The other thing I didn't mention, Laurent, which is quite important, I think, is as far as I know, you can't change your prediction equation that's being used in these machines.


When I said there's hundreds of different regression equations, and those ones that are more suitable to runners, and some that are suitable to rugby, or football, but not ideal, but more suitable to that population. You can't do that here. You're going to get a one-size-fits-all number. The larger limbs contribute a big proportion of this whole body impedance, where actually, we know that these limbs have a much lower contribution to overall body mass. There's another issue with the BIA stuff.


[00:57:32] LB: With BIA and the software, and this isn't just BIA, this would be relevant to DEXA, other gadgets we'll get into in a minute. Also, manual, or software assisted calculations for body fat percentage, even from skinfolds is going to be the fact that we've got other factors to consider, like how accurate are the scales you've been using, which is another number you add into the equation. Is it the same set of scales? Has the scales been calibrated recently? Is it on a hard surface, on carpet? What time of day? Is it before and after exercise, eating? All those things. Maybe we could just quickly mention the importance of all of those things as it relates to the data, these things crunch out for us?


[00:58:19] GC: Yeah. I think, you've summarized it well. I don't know how much more we need to say to that, Laurent. Most of these techniques, the more we study them, the more we realize, the more things we have to control. That's why I said right at the onset of this podcast, that the purpose of this paper was to look at the equipment under the eye of the applied practitioner, which is a very different lens, than looking at it under the eye of a researcher.


I think, that's something to keep stressing throughout that. This is what we're talking about, when all this cannot be controlled as we well know. I've implemented DEXAs, for example, in sports teams, and you get given a window. That window maybe before or after lunch. As much as you say, ideally, I like it first thing in the morning, what was no way takes 15 minutes-ish to do a scan. I've got 30 players. I'm not going to get them all through.


Now, what I would need is to do three a day over a period of time to make sure that we're all fasted, because there's no way I'm going to get a rugby player fast into lunch. It’s just really not going to happen. All you can do in that situation, you say, “Right. Well, last time you did it, you were fed. Can you try and feed a similar –” It just brings in a whole level of complexity, that as you say, is very hard to control.


[00:59:38] KT: I mean, that brings in an issue that I was thinking about earlier when you were talking, was part of the challenge for people like you who do this practice has to be educating and convincing the players, but especially the coaches of these kinds of complexities, that can't be easy. They want a number to know that this player is getting better, or getting worse, right?


To convince him, “Hey, wait a minute. This change from 10.5% to 11%, body fat, that's just part of the measurement error.” It may not mean anything. The coach is going to say, “Hey, dude. yYu need to straighten up and lose that half a percent,” right? I'm sure that that must be a challenge for you, guys.


[01:00:21] LB: It's the bane of my life. I'm sure it is for you, Graeme, particularly in a team setting. Competitive people, they start playing off each other, “Oh, my body fats higher than yours.” We'll get into that when we talk about why summer skinfolds might be a better way to go, Graeme. Because otherwise, we're going to run out of time, unless –


[01:00:40] GC: Laurent, something just came into my head very quickly, though. Maybe, if I was doing a version two of these papers, another caveat I should have put into it. That is that, maybe I've written this a little bit too much in the lens of a team sport practitioner. Some of the things that you've been talking about then, if you was working with an individual athlete. I was working one-on-one with a 100-meter sprinter. That might be a lot easier to get that person to come in in the same situation, and give him that, I don't need to get through a team before lunch. I could control it a little bit better. That's another context we have, Laurent. What, are you working in a team or an individual sport?


[01:01:20] LB: Yeah, absolutely. Well, so bringing it back to using methodologies that are practical, convenient, and so on. We've said that BIA is pretty much a prolific method nowadays. Something that's relatively new on the scene is ultrasound. I know, ultrasound is not new. It's been around for a very long time for other purposes. Specifically, for body composition and I know other potential areas are being looked at, maybe unconvincingly, fueling, and so on. What about ultrasound, Graeme? Is that an area you feel has some legs?


[01:01:58] GC: I think, it's interesting. That's my sit on the fence answer often, Laurent, which is reason I think it's interesting, I can see certain situations, where it could be useful. Now, there's a few things to mention is that what we're seeing emerging sport at the moment is much cheaper devices. A lot of the original research was done on the high resolution BMO devices, which basically, are medical devices that cost over 11, 12,000, something like that, plus an annual 1,000 phone software subscription. Take around about 20 minutes of effort. That does appear to be some decent reliability data, if you do all that.


There's no much cheaper A mod models out, which I think look interesting. As I touched on before, there was a paper suggesting that the more reliable than skinfolds, inexperienced practitioners. With experienced practitioners, maybe not so much. I think, another example and Kev touched on this before a little bit is, it seems that the inter-practitioner reliability could be better on it. Where you get two different skinfold practitioners, they may come up with quite different numbers. If they use the ultrasound, they may be a little bit tighter.


My interest in it has come on. Sometimes you work with athletes, we have quite a large abdominal region for skinfold thickness. That can be quite hard with skinfold calipers. I think, the ultrasound may come into its own on the larger athletes, particularly around the abdominal region, where it's hard to get on with skinfold thickness.


I think, if you're working with – if you was ISAK accredited, skilled in calipers, and you're working with reasonably lean athletes, I can't see from the literature, where it's advantageous over skinfold. Where it is sexy, as we said at the beginning, if you get a nice printer, and it tells you your percentage body fat, and it gives you all these different numbers, which have basically, just done a prediction equation, and you can pick which equation you want in it.


Again, you can just go from it using a [inaudible 01:04:08] words, literally Jackson and Pollock, and drop someone's body fat by almost 10%. The issue with it is the same as using these regression equations. I would encourage people, if they were going to use these A model for stones to simply report the sum of metals, like we do with ISAK again, but that might not be as sexy as what people want out of that machine.


[01:04:33] LB: Yeah. It's not about the sciency stuff that Louise Burke talked about, back when she came out with her paper, right?


[01:04:39] KT: I mean, we keep coming back to this, so maybe it's something to stress again, is for the listeners out there who want to do a good job of this, measuring body composition, the first thing you want to do, I think, is go and get your ISAK accreditation and learn how to do skinfolds rock solid and move on from there, maybe, if you want to get into the fancy technology. That is the fundamental thing that you want to do as a practitioner.


[01:05:07] GC: Correct.


[01:05:07] KT: Just go out and learn how to do the skinfolds properly, so that you can be as reliable as possible when you're making these measurements.


[01:05:15] GC: Kev, there's a reason why I mentioned that when we wrote the master's degree in sport nutrition at John Moores, we integrated the ISAK course into the expense and my boss hates me for doing it, because we cover the fees. I think, it's crucial. Even if you're then going to go on to use some of these ultrasound techniques, well then, the training of an ISAK, identifying the sites will make you a more skilled practitioner using that as well. I completely agree. I think, it's really important qualification for people to get.


[01:05:45] LB: Yeah, we're going to come back to skinfolds in a few minutes. Just quickly, I don't want to spend long time on a few methods here, but one area that is much nearer, but it does look really quite interesting is this concept of 3D photonic scanning. Whilst there may be some angles there, particularly with trying to turn that into body composition, as opposed to just comparing one avatar to another, for example, what did you guys find when you researched this? What are your thoughts about it from a practical perspective?


[01:06:16] GC: We didn't find a lot, to be honest. Particularly in athletic situations. That was probably why of all the methods that we covered in this paper, once I sat on the fence on it, but we concluded that quite an expensive technique and expensive to buy the equipment's, etc. At the moment, lack of athlete-specific validation. It's probably too soon to start to be in to recommend it in an applied setting.


I probably would like to see more done on this over the next few years. It looks interesting. It's rapid. They only take a few seconds. I think, around about 10 seconds to do. In terms of ripping through a team, it seems to have a low degree of training needed, but you just stand on the plate that will turn you around, and it scans you. It comes up with the avatar. I think, once you've got the machine, the costing then becomes pretty low, really.


There's a nice paper on rows, I think, we covered, which showed it was maybe useful for different segmental volumes. It got able to look into different regions, which is something that other techniques offer, such as BIA. I think, if I was to summarize this one, it's probably a watch this space. There's been some suggestions that you're not getting much differences between 3D and DEXA measures. I would imagine that it's something that's going to be less affected by hydration and things like that. Maybe the conclusion on this one should have been, let's get some more research done on this quickly, because it could be interesting. Now, Kev, have you seen much on this one?


[01:07:49] KT: I'm too old for that one.


[01:07:51] LB: It comes from the common industry, doesn’t it? Where they would put you in these booths and they scan you hey, presto, you're fully measured. You got a couple of thousand of measurements. I guess, that maybe combined with skinfolds, Graeme, could be a nice little combo.


[01:08:08] KT: I remember DEXA came out, everybody thought, “Oh, this is magic.” Then, you start looking into it, of course, like everything has limitations, and you got to be careful. I would just say, before we get too excited about it, to make sure that we, as Graeme said earlier, let's do the studies and see. I mean, I'm going to go back to my catchphrase, I'm skeptical, but I'm open minded.


[01:08:31] GC: I think, that's a good summary for this one. Skeptical and open minded is probably where I am on this one, and would like to see a lot more on it.


[01:08:39] LB: We've talked a lot about two particular methods, which are going to be the last two we'll have a chat about. There's the, what is referred to as the gold standard DEXA, and then we come back to skinfolds, which is what I want to end this this conversation on. DEXAs, I've had a number of conversations with guest experts on this podcast over the years, including [inaudible 01:09:01] all about gold standard, not gold plated, maybe. Both of you refer to lots of DEXA. Let's just focus on that a bit. What is it Graeme? Why has it persisted for so long? Why should we maybe move on to the final conversation in a minute, skinfolds as the preference for practice?


[01:09:21] GC: Yeah. DEXA was originally developed, as we all know, for assessing bone mineral content. Helping with osteoporosis identification. Based on the way that it measures, almost the side effect of it is it will throw out a lean muscle mass and a percentage body fat. Because of that, we got really excited about it. In some situations when the right controls put in place, it is a pretty reliable bit of kit. You can get some great data. You can get regional measures, so you can see how it's distributed in the arms, legs, etc.


I think, players buy into it. They like it. It takes out some of the skill of the skinfolds. Yes, you do need some training about putting people on the bed correctly, etc. I think, in many ways, it's pretty exciting. One of the issues is a few years ago now, the legality of it changed on DEXAs, which meant that to do a DEXA scan on any individual now, either needs full NHS ethical approval for a research study, or needs a prescription from a doctor.


Anyone who's doing a DEXA scan just to assess body fat, not as part of a research study, no need a doctor to prescribe it, because there is ionizing radiation. Now, the amount of radiation is almost laughable. You can argue that that's a ridiculous thing, and why have people started to bother about it. It's about 4 to 5 microsieverts. To put that into context, that's about daily background radiation, just from being alive. Double your daily background radiation. It's such a small amount, but you do need it. That creates a whole seam of hustle.


Then there's a second point, which is the technical standardization requirements, and the likes of Louise Burke,[inaudible 01:11:10] has done a lot of great work in this. Now we know that we need to control hydration, we need to control muscle glycogen, we need to control the time of the last feed, time of day. So many things that we need to control to get accurate. Then a specific problem we get working with rugby players, is that the machine was originally designed for osteoporotic old people. Probably not designed for a six and a half foot rugby player.


You've got an option when you put a rugby player on the bed, which is do you chop off the head and leave the feet? Do you chop off the leave, leave head? Do you bend the knees to 90 degrees? Or do you try and scan them twice and add it all together, and not just on height? I can tell you for a fact on width, you can't get a rugby player on it either, because their shoulders are too wide. Now, you've got the option of chopping off one arm and guessing what's going on at the other side, which makes it all complicated.


We had a look at that head on, feet off as part of each review. That changed body fat from around about 13% to 17%. Dependent on whether you're chopping off the head, or chopping off the feet. There's no guidance either what to do with a player who can't fit on the bed. People all come up with the wrong way of doing it.


Going back to what I said, I think is a research tool done a couple of times a year, it's exciting. As an applied tool. It's time consuming. You need to get people to a university, or a hospital. We need to control all them factors that we just said it's hard to control. If it's a tall athlete, we need to think about how we're going to do it. From an ethical perspective, we need a doctor's prescription, and we need to make a decision about how often we can do it. Because there is no strict guidance on that either, or ethics committees get quite uncomfortable if you wanted to do this, let's say, once a month. There's so many considerations we need to think about. In my experience as a practitioner, working with the likes of England rugby and that, has just made a tool that's almost impossible to use.


[01:13:21] LB: I can't believe we've managed to have a conversation about this for as long as we already have. We're still not done, because now we come to the humble skinfold, guys. This is always an interesting one. You've already mentioned issues, like is the equipment even calibrated? The difference between quality kit and appropriate competence in the technique, and so on.


Of course, I guess, the perception of it is that it is not as sciency, is not as high-tech. Could also be a consideration. Although of course, there's a big difference between somebody with a pair of plastic calipers, and somebody who's doing a full level two, level three ISAK profile, which involves all sorts of bits of kit, which in my experience, actually does come across quite impressive to the individual, because of the depth of the assessment, and marking the body up and all the different tools that you use and so on is usually quite intriguing to an individual. Graeme, just take us through now, what skinfold thickness is, and why is that relevant? Maybe the broader techniques, like ISAK, for example, which is more than just skinfold, of course.


[01:14:28] GC: Yeah. We talked about skinfold. We're basically talking about taking a bifold of skin and body fat. We're making sure that we're getting the subcutaneous body fat, and the skin and we're not pinching any muscle. Then, we're putting a set of skinfold calipers on and actually, measuring this. When I was learning this technique, or been taught this at university, it was all about a percentage. You would take these numbers, throw it into, like I said, the Durnin and Womersley equation, which is a classic foresight; bicep, tricep, the sub-capular, super iliac. Four sites, all upper body, you get a percentage. Then everyone was happy with the percentage.


Fortunately, then, along came IAKk, who we've mentioned a few times, who tried to standardize this, came up with a much more rigorous way of doing it. More sites, more accurate, teaching how to do the measurements, all things like the calibration of the equipment, and suggested that we now report it as a sum of them multiple sites that you use. Now, as we've said a few times, it takes skill of a practitioner. It takes training, whether you're level one, two, or three anthroprometers, as you as you mentioned before.


When I show a nice review on this, which I mentioned in our review, of all the techniques, it seems to be the one that's least affected by things that's hard to control in an athlete, such as hydration and glycogen and feed in and things like that. It's also one where you've got your anthropometric tape in your bag, and you've got your set of metal harp and then skinfold calipers, and it can be done almost anywhere in a relatively quick period of time. It can be done frequently to measure change over time.


That is why after reviewing all of these techniques, when it comes to applied practice, the technique that has probably been thrown away, because it's not as sexy is why we came with the comeback skinfolds always forgiven. Because in an applied setting, I do think it's going to be the one that gives us the best bang for our buck, providing we've got a trained practitioner.


[01:16:43] LB: Yeah. That's exactly what Kev was talking about, is this business of if you're going to do it, do it properly. Get trained to use your equipment, and so on. To the printouts. well, that information, there are ways of displaying that information, whether it's Excel, and its various charting capabilities, all the way through to a number of software platforms that will enable you to produce a lovely looking report. You do have it all, if you think about it, right?


[01:17:11] KT: May I just say that when I read this paper, when I saw this paper, especially the title, I was very jealous, Graeme, because I wish I'd thought of writing this paper, because it's what I've thought all along, is that I've used several of these techniques as the years have gone by, and you get fancy stuff, but they're all these limitations. In an applied setting, it's hard to beat the humble skinfolds. When I saw your paper, I was like, “God, he's so much smarter than I am. I wish I thought of this.”


[01:17:42] GC: I'll say before I fly, I come up with titles, and then think, we can make that into a real nice paper. I've done it with my paper to podium. I've done it with comeback skinfolds, and I've got another one coming out at the moment. I do like a nice, catchy title. You're exactly right. It's something that I've been thinking about for years. It came to a point, it was, I've got all these techniques available to me. I've read more on these techniques. This is what I teach. This is my job, but let's say most practitioners. I still use calipers.


I probably need to explain that in a scientific manner, as to why after going through that decision tree that we've put at the end in figure two, why I most of the time in applied practice, use the skinfolds. That's where it came from. Really emphasize, I still do use most of the other techniques on that decision tree, in some situations, in some research studies, etc. From an applied practice, yeah, comeback skinfolds, always forgiven.


[01:18:46] LB: That's brilliant, guys. Listen, we've thoroughly covered this subject. It's great to know that skinfolds have been forgiven, or your holiness is. Holy. Anyway, I think, there's a lot to take home from that. Listeners, just to remind you, there will be a transcript of this conversation, so you can read about it, you can listen to it, of course, and I'll link to all the other papers, resources, even the ISAK website, for those of you that may not have heard of it. You should get yourself trained, despite the limitations that COVID is having. I do believe there are courses now being run around the globe.


Graeme, you're pretty on it when it comes to social media and stuff as well, so for folks that want to follow you, and you got a website and Twitter and so on, what are the main ways of our listeners keeping tabs on you and what you're up to?


[01:19:40] GC: Yeah. Just, social media is probably easiest. Twitter is @close_nutrition. Instagram is just @closenutrition. Or the John Moores website, I'm easily findable. Yeah, I'm not that hard to stalk.


[01:19:55] LB: I'll be linking to all of those one way or the other. Well, see, Kev, if folk can read about our team link on our website, theiopn. If people want to be following you, you're also a little bit out there in Twitter, and so on, aren’t you, Kev?


[01:20:10] KT: Yeah, occasionally. @proftipper on Twitter. I do have an Instagram account, but I rarely mess with it.


[01:20:18] LB: I was expecting to see you with some TikTok superstar, Kev.


[01:20:24] KT: Right. Yeah. Exactly. No, I'm too old for that, I think. The main way would be on theiopn website, or Twitter.


[01:20:32] LB: I'll link to all of that. Kev, thank you as always. We, of course, will have you back. Next week, we're doing a podcast all about high-protein diet. Hopefully, that'll be our next actual published podcast. Graeme, you've been awesome, as always. Always appreciate your time, your contribution.