How You’re Being Manipulated By The Sports Drink Industry And What You Can Do About It.

Hey, folks, it's Ben Greenfield. And with me today is Dr. Tim Noakes, the South African physiologist who has been on this show in the past and has shared with us a great deal of valuable knowledge about electrolyte intake and also about something called the central governor. And today we're going to be discussing some of the concepts that Dr. Noakes lays out in his new book, which is called Waterlogged the Serious Problem of Over Hydration in Endurance Sports. I read this book, I finished it a couple of weeks ago, and it's pretty mind blowing in terms of the amount of knowledge that it contains that you never, ever learn. And I spent five years in university learning what was supposed to be everything you need to know about how to fuel the human body during exercise and did not learn any of the stuff that that Tim talks about in his book. So, Dr. Noakes, thanks for coming on the call today.

Thank you, Ben. I appreciate you having me back again.

So let's jump right in. You start this book out with a case study about this girl named Cynthia Lucero who is going to run the Boston Marathon. Can you talk about what happened there and why? It's a perfect way to outline why this book needs to be written.

Well, the tragedy for Cynthia is that we predicted this was going to happen. I predicted in 1992. We had the editors of Runner's World here. Sorry, it was 1993 and we had the editors of Runner's World here, including Ambie Burfoot, who wrote the introduction to my book. And the first lady had died from this over drinking during the Valley of the Giants race in California that very weekend. And I said, ambie, there are going to be many more American females who are going to die in marathon races unless we do something about it, because you guys are over promoting drinking in the United States and it's going to have tragic consequences. And so the next case that occurred was in the Chicago Marathon in 1998. But that case went under the radar, but Cynthia didn't. Her case was reported on the front pages of the Boston Globe and the New York Times. And so then I realized that this was the real case that would change everything. And particularly what was important was when it was reported, it said that she died because she drank too much fluid, including too much of a particular sports drink. And that it became. I really wanted to know what had happened. Unfortunately, we could get some of the medical records on Cynthia from the Boston hospital where she was treated. And once we had those that information, we could calculate exactly how Much she had drunk during the race, and it turned out she had done exactly what she'd been told to do. She drank 1.2 liters per hour. That's 40 ounces per hour.

And who had told her to do that?

Well, I can't say exactly, but she'd certainly trained with the group and they were advised to drink lots. But there was an advertisement in some of the running magazines in January 2002, and I have that advert, and it says, you must drink 40 ounces per hour or else your performance could suffer. And it has a picture, in fact, of a young woman running. And so had she seen that advert, that's clearly what she would have wanted to do. So the story is exactly what happened, that she just graduated with a PhD from a university in Boston, her family had come up from Ecuador to watch her finish the race, and tragically, she never reaches the finish. She collapses at 35km. She has all the symptoms of hyponatremia. She loses consciousness, she becomes confused, she loses consciousness and she's unconscious when she's admitted to hospital. And I don't know what happened thereafter. I can only speculate. But we do know that she was declared brain dead within 24 hours and her five organs were transplanted into five other people. And that was the tragic case. So her parents never got to see her finish the race.

It was a very kind of tragic way to write the book. But I mean, it gave me pause just because three months before I even opened this book, I was told the same advice by an exercise physiologist that I did a sweat sodium analysis and I was actually losing more than 40 ounces per hour. And he told me I needed to be drinking exactly that if I wanted to keep myself from decreased performance. So it's scary how much of this is still out there, despite this and other case studies that you lay out in your book. Now you get into the anatomy of humans and the way that we're built and the way that we're designed to thermoregulate. Can you explain a little bit of that in terms of how we actually handle heat?

Yes. And when I have written my previous books, of course I didn't know about this, but it was really only in 2004 that we suddenly began to realize that humans are long distance runners. And that's why we evolved. And if we hadn't been long distance runners, we wouldn't be where we are today. And that, of course, happened on the savannah of South Africa and East Africa. And I'd had a great interest in anthropology all my life, but didn't link it to running. So although I was very proud that humans evolved in Africa, and I knew the history of it, I didn't really know too much about it. But then when Dan Lieberman published the paper in nature in 2004, saying that we have all these adaptations which are specific for running and not for walking, then I began to ask the question, well, did we have other adaptations that could be related? And the first one you look at is, why are we such good hot weather runners? And of course, it's because we can sweat so much. But then what people hadn't understood was that if you're going to chase an antelope for four hours or six hours in the heat in the southern Africa, on the savannah, there's no water. You don't have time to find water. So it meant that these guys must have been hunting without water. And so therefore the idea evolved that people developed to run for four to six hours without drinking. And in the study, when. When the hunters are studied, what they do is they kill the antelope and then they drink the fluid from the gut and they probably drink blood as well. And so they delay drinkers. And then it made me realize that humans really are delayed drinkers. We don't need to replace the fluid loss as it develops. We need to replace it at the end of the day, when we have our meal at the end of at night.

Yeah, I like the way you explain it. In the book, you say that thirst is delinked from the actual water requirement during exercise.

Yeah, precisely. And then, because this has to be the reason that if you got over thirsty, you would stop running and the antelope would disappear, and we would never have evolved as we are today. So that made me realize that humans are designed to run with dehydration. And in fact, I wrote a paper in 1995 talking about the dehydration myth. But I just looked at the published literature, and the published literature is clear that the most dehydrated athletes win the races. And so that seemed to be the case to me. And in fact, when I was running competitively ultramarathons, we drank so little and we'd find. And that was the history of running right up till the 1980s, when suddenly these guidelines were produced that said you had to drink 1.2 liters per hour. The question is, how could it have been that for 100 years, athletes ran without drinking very much? Why all of a sudden do we need to start Drinking so much.

Yeah, exactly. I mean, like prior to that point, were you seeing a lot of issues in terms of heat management during exercise that that would have sparked this sudden urge or sudden encouragement to drink as much as you're losing, or in some.

Cases more quite the opposite. Now, I used to be the medical director of a couple of races in Cape Town particularly. We have a long 35 mile, 56 kilometer, Two Oceans Marathon. And I'd been the medical director and literally I would run the race and, and when I finished, I'd sort of amble over to the medical tent and there'd be a guy with blisters and another guy with something wrong and maybe there's an asthma attack or something, but that was it. We didn't see patients. And then all of a sudden, after 1976, when many, many more people started running and we started providing fluid at every few kilometers, every two or three kilometers, then you suddenly saw large numbers of athletes needing treatment collapsing after the race. And it took us a long time to realize that they actually just dropping their blood pressures and if you lift their legs, that's all they need. And in most of it it's simply that they're not adapted for running in the heat. And if it's a hot day, we know that we get 10 times as many people in the medical tent as when it's a cold day. On a cold day, no one comes.

So.

So it comes to the medical tent. So the heat is the key issue. And in my view, it's because people are not trained properly and they're not adapted for the heat and that's why they collapse. And then they compound it by drinking too much. So far from reducing the problems, we saw many more problems when people started drinking more during marathon races.

So if you're drinking when you're thirsty and that's still somehow causing dehydration, does that actually have an effect on your performance? Because what I have grown up with and what I was taught in school was that once you get to about 2% dehydration performance will start to significantly suffer.

Well, that's sort of the mantra for. From the United States Army Research Institute for Environmental Medicine, that it's kind of. I don't know where it came from, but that's the mantra that all those guys say. And they are the most influential people because they direct what happened at the American College of Sports Medicine. And to some extent they've directed what happened in the Gatorade Sports Science Institute. In other words, they direct all the advice that American runners get. And they have this mantra, and it's still embedded in the 2007American College of Sports Medicine drinking guidelines. So they have said, Noakes is right, you should drink to thirst. But if you're going to lose more than 2% of your body weight, then you must drink ahead of thirst. And there's absolutely no evidence for that. And again, I argue that very convincingly in the book that there's absolutely no evidence if you drink ahead of thirst that your performance is enhanced. In fact, it's impaired.

What about body temperature?

That's a great question. You see, water's got nothing to do with body temperature, or it's essentially got nothing to do with water body temperature, the factor that determines your body temperature during exercise is how fast you run, and the faster you run, the higher your body temperature. I present all the evidence for that. However, there is a phenomenon known as adaptive heterothermy, and that's a big name. And what it tells you is that for desert dwelling animals and humans evolved as desert dwelling animals, we have this ability to raise our body temperature when we've got drinking less water than we require. So there's a wonderful animal, the gemsbok, which can live in the desert at 45 degrees centigrade, it does not need to drink water. It gets all its water from the grass and things that it eats. So not the grass, the acacia plants, but what it does is it raises the body temperature 40 to 46 degrees centigrade. So if it's outside temperature 45, it loses temperature down that gradient. However, if you feed it with water, it immediately starts to sweat and brings the temperature down to 37. So as long as it's got water, it regulates its body temperature at 37. As soon as you take water away from it, it allows its body temperature to rise. And there are many other animals do the same. So what happens in humans, we show exactly the same response. If you don't drink as much as you need during exercise, for whatever reason, if you're in the laboratory trial and you're not getting any fluid during exercise, your temperature will be 1 degree centigrade higher than when you drink lots of food. But that's a biological adaptation which is of hugely huge benefit because it allows you to regulate your temperature without losing more fluids and sweating more heavily. So having a higher temperature when you're not drinking is a biological adaptation that is hugely valuable.

So far, as far as water intake, basically what you're saying is that the recommendations to avoid kind of venturing into that 2% dehydration range really aren't going to improve performance, may actually hurt you and you should drink when you're thirsty. That's kind of what you've laid out at this point.

That's correct. And the evidence is there that if you drink ahead of thirst, you become a demeter, you retain water, you become heavier than you need to be, and as a consequence your performance is impaired. And one of the studies which I didn't actually interpret properly early on when it was published, showed that you've got about 2 liters of fluid in your body that you have to get rid of during exercise. So technically you can lose two pounds or two, sorry, two kilograms, about four pounds of weight without changing body water content.

Four pounds?

Yeah. We haven't been able to show that. But in other words, we have looked now at people and see when does their body water content go down. And we find that they have to lose more than a kilogram or two pounds before their body water goes down. But I think we're still underestimating the volume of reserve water that you have because the gut is full of water and you probably extract that water initially when you start to lose water and become dehydrated. Now the point that what your weight on your scale that you lose, it's not all water and it's not a water that you need to replace. And people need to understand that.

So, you know, the one thing that we haven't really talked at all about yet is sodium and electrolytes. I know that we discussed this a little bit on a previous show, but you talk about the evidence in terms of what exists out there about how athletes competing in long duration events, what kind of risk there is for salt deficiency? Is there a risk at all in terms of becoming salt deficient during exercise?

Well, the way I read the literature is that there's absolutely no risk. And the reason I say that is because people have tried to induce sodium deficiency in free living humans and it's only possible if you restrict their sodium intake to nothing and you make them exercise three or four hours a day for at least seven days. Under seven days, you can't generate it. And what people have to understand is that when you exercise, you're actually excreting the sodium excess that you ingested the day before. So if our daily sodium requirements are about 2 grams per day, which is what I think they are in most athletes, maybe up to three grams. If you're exercising three or four hours a day, but your intake is six grams, then in fact, you've got three grams of sodium you're going to have to lose the next day in your urine and sweat. And so when we study athletes during exercise, they are excreting an excess that they generated the day before.

So are you saying that it's like during, say like the week of, let's say Hawaii Ironman, hot humid race, during the week of Hawaii Ironman, there's a lot of advice out there for athletes to say like be salting their food, almost doing like salt loading leading up to the race. I know that you, that you said before that taking in salt during the race is basically just going to drive you to lose more salt and not help you at all. But what about in the days leading up to the race using something like salt loading? Are you saying that that's not going to be beneficial either?

Well, it's really interesting because what happens with you have to be in salt balance every day or you're going to die. So every day you have to excrete the excess because if you accumulate it you'll body water content is going to go up and you're going to die from edema. So you have to get rid of the sodium every day. So if, let's say you came to the Ironman and you were sodium deficient, you would then replace all the sodium that you needed. It would be stored inside the cells. That's the only place you can store it. So an athlete coming to the Ironman, the only site of sodium deficiency could possibly have is in a storage site inside the cells.

And how much can you store?

Well, probably a substantial amount, maybe 10, 15 grams maximum, maybe 20 grams. And so you can see it would take you two days to fill those stores. Now what happens is you go and do the Ironman and you will start extracting from those stores if you need to. But again, this is a little bit speculative because all this work was done in the 1950s. So we know that there's more sodium in the body than we can account for and it has to be inside the cells and it has to be a reserve which you can actively source. If you are sweating a lot in for example, the Ironman and you're doing something exceptional, you can easily access that source and sustain your sodium without becoming deficient. But the point is that blood sodium concentrations are elevated in people running the Ironman. If they lose water and they become slightly dehydrated, so they're not sodium deficient. The only way they might be slightly sodium deficient is they might have extracted Sodium from their internal reserves, which they will fill up the next day when they go back and take more sodium in their diets.

And there's enough reserves there for 10, 12, 15, 17 hours.

Absolutely, absolutely. So the key, you know, if you want to know if you're sodium deficient, just measure your sodium at the end of the race in your urine. That's the key. It's not in your sweat. And if you were really sodium deficient, you would have no sodium in your urine and no sodium in your sweat. So if you can taste sodium in your sweat, you've got a sodium excess. And I'll bet that there are very few Ironman triathletes who can't taste the salt in their sweat.

In your book, you talk about Gatorade, which I know is kind of the dirty G word in the. And how it's influenced our hydration recommendations that we're exposed to in the world of exercise. And you talk about many of the studies that were done to develop Gatorade. What were some of the problems or the mistakes that were made in terms of generating that formula and the recommendations that came along with it?

You see, there are two types of science. The one science is you start the science without knowing what the outcome will be, and that's real science. When you influence the science that will produce an outcome that you want, then you're in trouble. And that's called Ben science. And what you have to look for. Is there any evidence that science was done in order to produce a predetermined outcome? And that. That's the question that one needs to ask. So there was once. So there are many studies that all cover. But the key study was 1992, in which it was Gatorade funded. And a group in Texas studied athletes of good quality who exercised for two hours in hot. In hot environmental conditions. And they drank either nothing or substantially more, up to 1.2 liters per hour. But the key was they exercised very hard in hot conditions at high intensities, and there was no convective cooling, or essentially very little convective cooling. And the conclusion from that study was that athletes needed to drink 1.2 liters per hour. And that then became the mantra with the American College promoted in 1996. They came along and said that all athletes must drink 1.2 liters per hour. Now, what's the problem? The problem is that that study was of very good athletes exercising extreme heat when there was very little convective cooling. And I would ask the question, why would you set up an experiment like that, except to have a very high sweat rate so that you could then tell people they had to drink a lot during exercise. Now, someone has got to come to me and say, that's not true. The problem was Cynthia Lechero now goes and runs the Boston Marathon at 10 degrees centigrade with a facing wind and it's under cloud cover, and she's told she must drink 1.2 liters per hour, even though she's running at 8 kilometers an hour. She's not cycling at 40 kilometers per hour or 35 kilometers per hour at a very high intensity. She's jogging. And her sweat rate, I know, will have been 400 to 500 milliliters per hour. Why should she drink at 1.2 liters per hour when she's sweating at 400 milliliters per hour? Now, had those people in 1992 put Cynthia Lucero on a treadmill in Boston at 10 degrees centigrade and had her run at 8 kilometers an hour, they would have found she sweated at 400 milliliters per hour. Then the drinking guidelines would have been, everyone must drink at 400 milliliters per hour. And they would have been equally wrong, but they would have been more correct for athletes like Cynthia Lucero. So that was the problem. The design was, in my view, to find conditions where people would sweat a lot so that then people would be told to drink a lot. And it was. The guidelines were never modified for people running slowly in cold conditions when they absolutely don't need to drink that amount.

You know, one of the things that appears to be the case in your book is that they didn't separate when they tested Gatorade, the effect of the actual carbohydrate in the Gatorade. Did I understand that correctly?

That's true. And in fact, I was asked that even just this morning, what's the evidence that you need the carbohydrate? Well, the evidence for that does come from other studies, but again, they were done in people who have fasted for 12 hours. So I know I can prove that you need carbohydrate during exercise. If I take carbohydrate adapted athletes, that is, athletes who are always eating lots of carbohydrate. And I starve them for 12 hours. If I did it for 24 hours, it'd be even easier to prove it. But you starve them for 12 hours, and then they are going to run out of carbohydrates sometime. If you can make sure the exercise is long. Enough and it was done. And after three hours, the people's performance went down and when they took carbohydrate, it went up, it was, was improved. So that's the one group of studies in prolonged exercise showing you could benefit from carbohydrate. But again, they didn't look at the alternate explanation that if you had people who were fat adapted and who may well not need carbohydrate during exercise. The other problem is that carbohydrates do clearly have some sort of brain stimulatory effect. And as soon as they hit the back of your mouth, they improve your performance. And so you'll always get that effect of carbohydrates in acute studies lasting, say less than an hour, if you take in the carbs, they are going to help you benefit performance. But again, these are carbohydrate adapted athletes who are used to the stimulation.

But in the actual Gatorade studies, did they control the studies with a group that was consuming a carbohydrate plus electrolyte solution with a group that was consuming an electrolyte solution only? I mean, is it the glucose in the Gatorade that can help you and not the electrolytes?

I would guess so. I mean, what they did compare, they did compare to water and they generally found that taking more water up to a certain amount improved performance and taking more carbohydrate improved performance. But for example, drinking a little bit of carbohydrate was, or should I say to the verse, drinking a lot more water was almost as beneficial as drinking a little carbohydrate. So there are interactions, but no one really looked at what role the electrolytes. And I would say the electrolytes because they play no real biological role. You don't need them during exercise. I can't see how they would make much difference.

So from a physiological perspective, to geek out on this a little bit, you talk about exercise associated hyponatremia in the book this water intoxication. How does it actually happen? I mean, what happens as you're taking in water or drinking as much as most folks are recommending these days?

Well, let's make the point that the first problem is the behavioral problem. There's no biological drive to make you over drink. You have to be told to over drink and you have to believe it and then continue to do it. So that's the first problem. Now secondly, most people who overdrink will simply start passing urine and they will stop at the side of the road and find that they have to pass urine so much that they'll say, gee, I'm over drinking, and they'll stop drinking. The problem is that people who develop hyponatremia secrete the hormone antidiuretic hormone in excess, and that causes them to retain the water. So for whatever reason, the body's responding completely abnormally, and they drink to excess and they retain the water, and they become progressively more waterlogged and the brain doesn't detect it, and they continue to drink even though they are killing themselves. What happens? The water is retained, and then the brain starts to swell. And because the brain is contained in a rigid skull, it cannot swell too far. So it swells and it swells and it swells, and then the pressure starts to rise, and that obstructs the blood flow into the brain. So you get areas which become underperfused and they stop functioning. And the first thing that happens then is that your general brain function goes down, so you become unconscious. Then the certain parts of the brain may be underperfused and you have epileptic seizures. And if it goes further, you stop breathing because the brain's. The breathing centers are not getting an adequate blood supply, so they stop working and you stop breathing. And that, unfortunately, is terminal. You can't reverse that.

And you see a lot of this in specifically, like, Ironman triathlons over the past few decades, right?

Well, I managed to find that there were more than 600 cases of hypernatremia.

I know now in the New Zealand Ironman, that rate significantly dropped. You were somewhat responsible for that, correct?

Well, I wouldn't claim all the responsibility. My colleague, Dale Skeedy was the man.

And what did you do? How did you. How did you do that? What did you tell the athletes? Or how did you kind of achieve the reduced rate of hyponatremia in that race?

Well, the interesting thing was that they had 14 hospitalized cases of hyponatremia. People were unconscious. And this happened in the capital of New Zealand. And so what happened was that if they had 15 cases, they would have had to shut down the. And had a medical emergency and called all the doctors in to treat the problems. And the doctor realized he didn't want to get all his colleagues out the next year. So he said, we've got to do something about it. So what he did was he reduced the number of seconding stations on the cycling leg and on the running leg. And so you could only get fluids every 20 km in the cycling and every 5 km in the running leg. And he told everyone, don't over drink. He told them, you may not over drink. You may drink only to thirst. And never, ever, ever drink more than 800 milliliters per hour. And that reduced the incidence from 14 really serious cases, I think, to one the next year. And so that that was the difference that made all the difference.

In your book, you say that imperfect health has always been perfect health. And you say that we're not going to self destruct if we want to go run the Comrades Marathon or complete the Ironman Hawaii Triathlon. What exactly do you mean when you say that imperfect health has always been perfect health?

That I stole from that wonderful book, God's House. In God's House, I think that was the name. And I was given that book by in fact, the person who asked me to write the drinking guidelines for the International Marathon Medical Directors Association. He said, if you haven't read this book, you're not a doctor, you can't be a doctor. And it's a wonderful book about personal and going through his internship and all the problems you face and working too hard and having patients who don't survive and so on. And imperfect health is what we are. It's just doing your best with what you have. And what happens in medicine is we look for all these abnormalities and we try to correct them. And you shouldn't be doing that because the body is quite capable of coping with these imperfections. And that's the problem that we are so over medicalized and over medicated. And that's what happened in running. You know, we didn't understand what we were doing. And we were saying the human body is imperfect. It can't get through the ironman without drinking 2 liters an hour or taking in all the salt and all this carbohydrate. And the reality is that humans are profoundly successful species. We are in incredibly robust. And our robustness is such that we can easily do the Ironman drinking relatively little and eating relatively little. That is our design. That is our perfect design, which in fact is perfect. You can't improve it by adding all this medical medication and all this supplements and so on.

Gotcha. Okay, that makes sense. So you've got these athletes with hyponatremia. I know a lot of doctors and people who work in medical tents, people who end up in medical tents. Listen to this show. What do you do? Is there a problem with what's being done right now when people wander into a medical tent after having had too much to drink? And what are kind of the recommendations if you find yourself in that spot where you have taken on too much water.

Okay, well, it's really simple. If you walk into a medical tent and you see lots of drips hanging up, intravenous drips hanging up, and if you see all the blades lying flat, then just get out of there because you're going to get killed. Just get out of there because the people running that medical tent have not the first idea how to treat you. On the other hand, if you come into the medical tents that we run, you will see all the beds with the one end lifted up, and that's where we will put your feet. You'll put your feet up and you won't see any drips. You'll see none. And then, you know these guys know what they're doing. And so when you come into my medical tent, the first thing I do is I look to see whether you're conscious or not conscious. If you're conscious, I know you've got whatever is wrong with you is irrelevant or it's minor. When I see you're unconscious, I know that I need all the medical help I can get, and I call in all the experts to help, because you could have had a heart attack, you could have had heat stroke or you could have had hyponatremia. So we will immediately examine you to see is your heart beating, is your cardiovascular system stable? If it's stable, well, you haven't had a heart attack, then I know you've either got heat stroke or you've got hyponatremia or maybe something else but less common. So we'll immediately measure your rectal temperature, and if it's 42 degrees centigrade, we will treat you for heat stroke. At the same time, we will take blood and we'll measure it for your sodium concentration. And if your sodium concentration is normal, then I know you've not got hyponatremia, then I'm. Only then will you be allowed to receive intravenous fluids. We would not normally treat. We don't use intravenous fluids. But if Your sodium is 140 or higher, yes, we will consider giving you intravenous fluids, but only then. So then we have caught out the major causes of the problem. The rest of the patients who come in are fully conscious, but they're a bit dizzy and hypotensive. Their blood pressure is a bit low. We lift their legs up, and within 30 seconds they say, doc, I'm feeling fantastic. Can I go out? And you say, no, you actually must lie down. For another 10 minutes, 20 minutes, 30 minutes, let your circulation sort itself out and then we'll see if you can stand. And as soon as you can stand for a minute or two without being aided, then you can leave the tent. And if you do that, that's all you need to do. And it makes it so simple. But what happens is people say, oh, this athlete's got dehydrated. They heat illness. Those two diagnoses do not exist. You either have heat stroke or you don't. If you don't have heat stroke, then you've got a low blood pressure for some other cause and we'll sort you out by getting your legs up. And the confusion is this industry driven concept that dehydration is a condition that can cause collapse. It doesn't. It's got nothing to do with it. And so finally, you know, if the athlete's dehydrated, they will say, I'm thirsty. So if we ask athlete, are you thirsty? He says, no. Then I say, then you're not dehydrated and whatever's wrong with you, it's got nothing to do with dehydration.

Wow. So in terms of drinking to thirst, I just wanted to throw this in there because I've done it before. I do sometimes find that in hot, humid conditions, I can get close to 40 ounces per hour. Drinking to thirst. I know some people say that you're never going to come close to drinking enough, but I've found that my body kind of seems to adapt based off of whether I'm exercising. And in cold conditions, you know, hot conditions, humid conditions, it's almost like I automatically vary water and take based off of where I'm at. Have you found that to be the case when you're telling people to drink to thirst? I mean, does it really vary depending on conditions?

Absolutely it does. And we don't always understand the conditions that make things different. But you see, you're cycling hard. You can easily lose 1.2 liters power. If you play American football, you can lose up to 3 liters pound. We know that Haile Gebri Selassie loses 3 liters now when he's running the marathon and he will lose six to seven kilograms. And he actually does drink far. He drinks up to 800 to 900 milliliters per hour, which is remarkable for a man running that fast.

Yeah, wow.

He's two kilograms every hour that he runs.

You go over a ton more research than we've actually covered in your book Waterlogged. And this is in my opinion, a book that everyone should pick up. It's heady enough to where I know that those who like to geek out on this stuff will enjoy it, but there's certainly it's written in a way that's very understandable. And so I will make sure that I put a link to this book in the show notes and a few of the notes that I took when I was reading the book, some of my takeaways in the show notes. And then if you have questions after having listened in, then go ahead and just leave them right there in the comments underneath the show notes for this episode with Dr. Tim Nokes, and I'll be sure to hunt down an answer for you. Dr. Nokes, thank you so much for coming on, talking about this problem of over hydration.

Thank you, Ben, again, for having me. I really appreciate it. I really appreciate you getting these ideas out. I was driven by my concern. Would you believe it, last week there was a death from hypanatremia in a paddling race on a river in Texas. And this guy out paddling, I think it was an incredible race. It was like 200 miles. But after 90 miles, this guy went unconscious and he died before they could treat him. And it was clear he was over drinking. And so he still had the wrong idea. And in fact, tragically, there's a picture of him paddling and he's got a camel back and he's sucking on the water. And I can imagine that he was doing that for the first 19 hours of the race and that was that half. You know, you're not doing really hard work when you're canoeing. And so he was over drinking. And it's a tragedy. It's still happening and it's absolutely preventable.

Well, I appreciate that you're bringing this knowledge to the masses with your book. So thanks for your time today. And folks, this is Ben Greenfield and Dr. Timothy Noakes signing out from BenGreenfieldFitness.com.