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Busting Myths About Riding in the Heat and Cold, with Dr. Stephen Cheung

We bust myths about exercising in the heat and in cold weather. We are joined by Dr. Stephen Cheung, one of the world's preeminent environmental physiologists.

Trevor Connor Fast Talk Podcast Cornering and Descending

At Fast Talk, we love a good myth. More than that, we like busting them. From the age-old myth about sleeping in a room with plants to the myth of lactic acid, Coach Connor and I enjoy applying science to firmly-held beliefs and turning worlds upside down—or at least correcting misinformation.

Today our focus is the large number of myths about riding and racing in the heat and cold. First, a reminder that we previously covered training in such conditions in episodes 21 and 35. While we’ll cover some of the physiology in this episode, check out those shows for a deeper dive into the mechanisms at play. Today, it’s all myths.

We start with some general myths about temperature: are there hot and cold riders? Good question. Then we move to myths about heat: Can you adapt? Does pouring water over your head help? And should your drink mix match your sweat? Finally, we tackle myths about the cold: Can you adapt to the cold? Should you over- or under-dress? Can you damage your lungs? That and much more.

Today, we’re joined by Dr. Stephen Cheung, a professor in the kinesiology department of Brock University in St. Catharines, Ontario. He is one of the world’s preeminent environmental physiologists and studies how humans perform in extreme conditions. He’s a well-respected author, the chief sports scientist at Baron Biosystems, makers of Xert, and he essentially tortures people as a job, which sounds pretty sadistic, and fun.

One other note before we get into it: in this time of online symposiums, Dr. Cheung is organizing a “Virtual Environmental Ergonomics” series. For more info, visit www.icee2021.com.

Today we’ll also hear from Nick Legan, Shimano’s road brand manager and a gravel racing expert, who has spent many an hour riding in extreme conditions, and Whitney Garcia, a former pro triathlete who raced in the heat of Kona and other hot climes throughout her career.

So, get your slushies, your bar mitts… your embro? No skip the embro. Let’s make you fast!

  • Burdon, C. A., Hoon, M. W., Johnson, N. A., Chapman, P. G., & O’Connor, H. T. (2013). The effect of ice slushy ingestion and mouthwash on thermoregulation and endurance performance in the heat. Int J Sport Nutr Exerc Metab, 23(5), 458-469. doi: 10.1123/ijsnem.23.5.458
  • Cheung, S. S. (2010). Advanced environmental exercise physiology. Champaign, IL: Human Kinetics.
  • de Ruiter, C. J., Jones, D. A., Sargeant, A. J., & de Haan, A. (1999). Temperature effect on the rates of isometric force development and relaxation in the fresh and fatigued human adductor pollicis muscle. Exp Physiol, 84(6), 1137-1150. doi: 10.1017/s0958067099018953
  • Ferguson, S. A. H., Eves, N. D., Roy, B. D., Hodges, G. J., & Cheung, S. S. (2018). Effects of mild whole body hypothermia on self-paced exercise performance. J Appl Physiol (1985), 125(2), 479-485. doi: 10.1152/japplphysiol.01134.2017
  • Hou, T. T., Johnson, J. D., & Rall, J. A. (1992). EFFECT OF TEMPERATURE ON RELAXATION RATE AND CA2+, MG2+ DISSOCIATION RATES FROM PARVALBUMIN OF FROG-MUSCLE FIBERS. [Article]. Journal of Physiology-London, 449, 399-410.
  • Munoz, C. X., Carney, K. R., Schick, M. K., Coburn, J. W., Becker, A. J., & Judelson, D. A. (2012). Effects of oral rehydration and external cooling on physiology, perception, and performance in hot, dry climates. Scand J Med Sci Sports, 22(6), e115-124. doi: 10.1111/j.1600-0838.2012.01510.x
  • Nielsen, B., Hales, J. R., Strange, S., Christensen, N. J., Warberg, J., & Saltin, B. (1993). Human circulatory and thermoregulatory adaptations with heat acclimation and exercise in a hot, dry environment. J Physiol, 460, 467-485. doi: 10.1113/jphysiol.1993.sp019482
  • Oksa, J., Ducharme, M. B., & Rintamaki, H. (2002). Combined effect of repetitive work and cold on muscle function and fatigue. [Article]. Journal of Applied Physiology, 92(1), 354-361.
  • Oksa, J., Rintamaki, H., Makinen, T., Hassi, J., & Rusko, H. (1995). COOLING-INDUCED CHANGES IN MUSCULAR PERFORMANCE AND EMG ACTIVITY OF AGONIST AND ANTAGONIST MUSCLES. [Article]. Aviation Space and Environmental Medicine, 66(1), 26-31.
  • Oksa, J., Rintamaki, H., Makinen, T., Martikkala, V., & Rusko, H. (1996). EMG-activity and muscular performance of lower leg during stretch-shortening cycle after cooling. [Article]. Acta Physiologica Scandinavica, 157(1), 71-78. doi: 10.1046/j.1365-201X.1996.452172000.x
  • Racinais, S., Moussay, S., Nichols, D., Travers, G., Belfekih, T., Schumacher, Y. O., et al. (2019). Core temperature up to 41.5 masculineC during the UCI Road Cycling World Championships in the heat. Br J Sports Med, 53(7), 426-429. doi: 10.1136/bjsports-2018-099881
  • Rissanen, S., Oksa, J., Rintamaki, H., & Tokura, H. (1996). Effects of leg covering in humans on muscle activity and thermal responses in a cool environment. Eur J Appl Physiol Occup Physiol, 73(1-2), 163-168.
  • Scott, E. E., Hamilton, D. F., Wallace, R. J., Muir, A. Y., & Simpson, A. H. (2016). Increased risk of muscle tears below physiological temperature ranges. Bone Joint Res, 5(2), 61-65. doi: 10.1302/2046-3758.52.2000484

Episode Transcript

Chris Case  00:06

Hello, and welcome to Fast Talk your source for the science of cycling performance. I’m your host, Chris case. Here at Fast Talk we love good myth. More than that we like busting them from the age old myth about sleeping in a room with plants to the myth of lactic acid coach Connor and I enjoy applying science to firmly held beliefs and turning worlds upside down, or at least, correcting misinformation. Today, our focus has a large number of myths about riding and racing in the heat and cold. First, a reminder that we previously covered training in such conditions in episodes 21 and 35. While we’ll cover some of the physiology In this episode, check out those shows for a deeper dive into the mechanisms at play. Today, it’s all myths. We start with some general myths about temperature are their hot and cold writers. Good question. Then we move to myths about heat. Can you adapt? Does pouring water over your head help? And should your drink mix match your sweat? Finally, we tackle the myths about the cold. Can you adapt to the cold? Should you over or under dress? Can you damage your lungs that and much more. Today, we’re joined by Dr. Steven Chung, a professor in the kinesiology department of Brock University in St. catharines. Ontario, is one of the world’s preeminent environmental physiologists, and studies how humans perform in extreme conditions. He’s a well respected author, Chief sports scientist at Baron biosystems, makers of exert, and he essentially tortures people as a job, which sounds pretty sadistic and funny. One other note before we get into in this time of online symposiums Dr. Chung is organizing a virtual environmental ergonomics series. For more info, visit www.ic e 2020 one.com. Today we’ll also hear from Nick leagan. Shimano is road brand manager and a gravel racing expert who has spent many an hour riding in extreme conditions. We’ll also hear from Whitney Garcia, former pro triathlete who raced in the heat of Kona and other hot climbs throughout her career. So get your slushies, your bar mitts your embro? No, skip that, bro. Let’s make you fast.

Chris Case  02:37

Well, it’s been since Episode 38, believe it or not two years since we’ve had Dr. Stephen Chung on the program. So it’s great to have you back. I know you are a leading expert in environmental physiology. And that is a very interesting term in itself. So thank you for joining us. And please explain what that means.

Trevor Connor  02:57

I just want to point out you wrote one of the textbooks that a lot of schools around the world use for environmental extremes. So I mean, this is truly your area of expertise.


Yeah, first off, thanks for having me back, folks. And you’re right, Trevor I, I did write a graduate level textbook on environmental physiology. And I’m actually working on the second edition right now during this pandemic. But what is environmental physiology, it’s really looking at extreme environments, whether it’s cold, whether it’s he, whether it’s cold water, high altitude, microgravity, diving, air pollution, all of these things, and what impact that has on our ability to kind of perform as athletes or as workers. So the fun thing about the field is we get to really push our body to its limits, and that we get to really make an impact on everyday life, whether it’s population health, looking at global warming, and how we develop better heat policies, with different cities to working with Olympic athletes preparing for things like Tokyo or hot weather events. And also with workers. I’ve done a lot of work with everybody from firefighters to Ultra Deep miners, to Coast Guard, looking at search and rescue policy to try to make kind of work a lot safer also. So it’s a really fun interesting, both basic field and very applied field.

Chris Case  04:27

Yeah, it sounds amazing. And I bet at times you get to put people in extreme conditions in a laboratory setting which some would probably call torture, but I bet there’s rules against torturing people.


Yeah, there’s there’s an old saying in my lab that no one’s ever comfortable. If you’re comfortable with and we’re doing something wrong.

Trevor Connor  04:48

This you do a study where you had people shivering for 24 hours straight.

Chris Case  04:54

Yeah, it was. You mean mean person

Trevor Connor  04:58

had to bring that up.


But yeah, that was a study we did in 2010. That was a contract with the Coast Guard answer to rescue here in Canada looking at trying to simulate Arctic survival, we’re trying to look at, Can people sustain their shivering capacity for 24 hours, keep in mind that if you’re stranded up in the Arctic, it might take five to seven days to really rescue you. So all of the existing models were based on kind of two hour type long studies, which will be a really long kind of lab study. So we decided to really push the envelope and go for 24 hours, and they were eating survival rations, they had no water, they had no entertainment, except for a deck of cards. So it was pretty extreme. But it was, it was challenging to do, but I think it was really worthwhile in terms of the science we got out of it at the end.

Trevor Connor  05:50

So what names were they using to describe you by hour 23.


Both the participants and my lab members, they had all sorts of names for me, by the end, keep an email. Yeah, the participants were in there for 24 hours, we were in there for 40 plus hours as a team kind of from before the participants arrive to afterwards. So yeah, it was a it was a pretty challenging study. But again, it’s those are the kind of, you know, type two, kind of fun that you talk about afterwards.

Chris Case  06:22

It certainly speaks to your expertise in this in this niche of physiology, which we want to dive more into both on the cold side and the hot side. So maybe we should start with a brief, brief overview, a quick physiology lesson here, when it comes to temperature extremes.


Sure, well, I mean, what happens when you get hot is that you have a big competition for blood flow, you, you’re trying to keep cycling, you’re trying to send blood to your muscles, but at the same time, you’re getting very hot, both from the heat that you’re producing by exercising, and also because of the environment. So as a result, in addition to trying to send blood to your muscles, you’re also trying to send blood to your skin to get rid of heat by increasing the blood flow, trying to send more blood to the skin and also for the sweat glands to start sweating and eliminate heat that way. And you’re also shutting down a lot of other kind of non necessary or non critical systems like to your gut. So I’m sure we’ve had episodes before, where you’re talking about training the God and the impact of that. And so there’s a lot of systems at play. But ultimately, you know, instead of really being devoted to sending blood to your muscles, you are kind of having a lot of impaired blood flow to a lot of other systems too. So that’s what’s happened in heat. And then in the cold, the real challenge is trying to maintain heat in your body, instead of trying to get rid of it, you’re now trying to maintain heat. And the first thing the body does is try to protect the core, the torso and the brain. So the heart and the lungs and the brain itself, with the idea that you know, those are the systems you really need to live. So what becomes less critical is the muscles and so you have less blood flow going into the muscles, instead, your shunting or or restricting that blood back to the really vital organs to stay alive. So it’s kind of it all comes down. A lot of these reasons why we have impairment comes down to all these challenges in the priority for where the blood is going, as you are exercising, whether in the heat or in the cold.

Trevor Connor  08:56

So someday, I think you You are the one who told me this many years ago, but I really liked this image is to think, you know, we think of blood as a transporter. And you think of it as transporting oxygen, you think of it transporting nutrients, but it’s also a heat transporter. So if you are in hot weather, you want to get that blood up close to your skin, because it’s taking that heat from your core, getting up to the skin where it can get it out of your body. But in cold weather, it’s the exact opposite. You don’t want to lose any heat. So you keep all that blood close deep inside your body where the heat can’t really escape.


Yeah, absolutely. So you know, let’s say you’re writing along at 250 watts or 200 watts, you’re still producing the same amount of kind of heat within your body. But the challenge is that whether you’re in the hot or the cold, but if you’re in the heat, you are also having the external environment. So if you’re, you know, back in the old days in a tour of Qatar or in 2016, where the worlds were there Or every year and tore down under, you have, you know, a lot of extra heat. So not only are you trying to get rid of the heat that you’re producing in your body, but you are also having additional heat kind of dumped into your body by the environment. So you’ve kind of facing a double whammy, the main way the body responds is it, it is increasing a lot of blood flow to your skin. And to try to kind of get rid of that he kind of like a radiator, try to get it, get that warm blood out near the surface of the skin so that it can dissipate to the environment. And again, the other way is through sweating. So those are the big challenges that you’re trying to face again and Nicole, you’re still producing a lot of heat. And that’s what shivering is all about. So when we talked about can you shiver for 24 hours, that’s the body trying to maintain extra heat, even if you’re not exercising to keep your body at 37 degrees Celsius around 9697 98 degree Fahrenheit. So yeah, the blood plays a huge role as a kind of heat transporter throughout your body. In addition to to moving oxygen around, which is what we’re more interested in most of the time in terms of exercise, we’ve talked a bunch of times on the show about efficiency. And typically your average cyclist is somewhere 20 to 25% efficient, meaning that when they’re burning carbohydrates, when they’re burning fat, only 20 to 25% of that energy is actually going into the bike that other 75 to 80% is being lost as heat. But as you said, if you’re if you’re shivering, that heat is beneficial. Yeah, so I mean, he doesn’t kind of in that sense of waste product all the time. It is kind of a necessary part of life. It is again how homeo therms, like humans who are warm blooded maintain kind of a certain level of body temperature throughout. And what’s really fascinating about humans is that you know, from the day you’re born to the day you die, you know through kind of thick or thin whether you live in heat, hot environments, live in cold weather, you’re exercising, the body is just phenomenally capable of maintaining your body temperature within a really, really narrow range. And that’s one of the fascinating things that continues to kind of inspire me as I study is just how is the body able to do this? I mean, if you are running a marathon, the marathon de Saab? Yeah, versus if you are kind of stranded in the Arctic, for the large part, humans are still able to keep the body temperature really, really steady throughout the course of a day throughout the course of its life.

Trevor Connor  12:50

So we’re not gonna dive too deep into the the general physiology here because a we’ve actually already done two episodes on that. And I believe we have side interviews with you. Um, both of them. I know definitely on the cold weather one. Yeah, absolutely. Episode 21. We talked about managing heat. Episode 35, we talked about dealing with cold weather. I think that’s where I got my giant soapbox, because everybody knows my so I’m curious, like, when are you not on? So my biggest soapbox is people under dressing. And we will get to this and I’m excited. Um, but today, really what we want to dive into is all the myths about training and racing in both the heat and the cold. And I think there’s gonna be a lot of fun because there’s a lot a lot of myths out there. Where do we want to start? I guess you you sent us a kind of a general one. That might be a good starting point.

Chris Case  13:46

Yeah, I think we’re right at the top of the list is the question. Are there really hot weather in quotes or, quote, cold weather riders?

Trevor Connor  13:57

And before you answer that, remember, you are a Canadian, we are contractually obligated.


Yeah, yeah, absolutely. And that that’s the hilarious thing is how people’s kind of perception change. I was just being I was just an external examiner for a PhD from Australia, who was looking at the impact of kind of heat and ambient temperature on high intensity training. Basically, can you do intervals as hard and how does it impact it? And he and, you know, their their code condition that they claim was 13 degrees Celsius. And that the student was actually from, from Wisconsin, and I’m going man, your perspective has changed after four years in Australia, if you think 13 degrees Celsius is now cold. But yeah, so so to get back to whether they’re hot or cold weather writers, I think, ultimately, you know, we’ve seen examples of is, you know, enduring was Known for his love of heat and it was claimed he never performed well. And the the wealth of which was an April at the time because it was still cold and everything but yet he thrived in the heat. You have other guys who just really love the code, you got cyclocross racers who really love it, and it gets starts to get really below zero, below freezing. And so you get that wide range and and the big question is, is it physiological is a psychological or is it kind of cultural and I think it’s probably more of the psychological and the cultural then pure physiology. And cuz, you know, genetically in terms of our capacity to respond to heat or cold, we’re pretty similar, whether you’re born in a hot environment, or born in a cold environment, and grow up there. But But I think so much of it is cultural. I mean, if you are kind of a, you know, I was born in Hong Kong. So if I grown up there my whole life in a kind of a Southeast Asian tropical type climate, and I suddenly the first few years in Canada, I was young at the time, but I’m sure, I felt that was ridiculous. Whereas now, it’s not as much of a stress. So I think a lot of it is cultural. And it’s, it’s really hard to do those kind of cross sectional, kind of longitudinal type studies, because, you know, is it you know, is it a case of actual physiology? Or is it because, you know, way back early days, I had a really good race when it was boiling hot once. So now I think, Oh, I’m a hot weather writer, and I, I now kind of self select myself to become more of a hot weather writer and, and try not to write out as much in the code. And so I think a lot of it is that kind of cultural kind of stimulus, rather than any kind of ingrained Physiology or genetics. I know, for myself, I, you know, I don’t necessarily love the hot hot weather, but what really gets me is that part that’s just above freezing, where it’s a kind of a cold, winter day with a gale force wind blowing, and it’s kind of that gray skies, that’s probably my biggest Achilles heel, whereas when it’s well below freezing, you know, I I actually don’t mind it, I’m I go and ski and do all sorts of other stuff outdoors without complaining, but it’s those you know, there’s, I think everybody just has that built in experience. And I think it is comes to that it’s that experience that makes you more of a one type of writer or another.

Chris Case  17:49

Is there some truth to the fact that quote, unquote, circulation plays a role here, some people have better circulation, so blood stays in their extremities in their fingers and toes? If it’s a really cool day more than others? And so they feel it less? Or is there is that a myth as well? On Oh, that’s


definitely not a myth. We know from studies of, of people with frostbite injuries, that there are definitely racial differences. And the studies looking at kind of military and frostbite does show that particular kind of ethnic backgrounds, and particularly African Americans, and also individuals from the Caribbean, and also kind of somewhat intermediate, or would be Asians, that that have more propensity for frostbite compared to Caucasians. So there are definitely epidemiological studies showing that there are certain groups that are more at risk, and it does come down to differences in blood flow. And that’s actually in the hands and the toes. And that’s definitely one area of study that I kind of have done a lot in over my career and to show that there is definitely huge individual variability in terms of blood flow. And I think that’s where the discomfort really comes in, especially in the code is just trying to keep your hands cold or warm, and your feet warm. And I know if those go that, you know, all other bets are off I can have to warm is core on Earth, but if my hands and feet are cold, then you know, I don’t want to be outside anymore. So I think there definitely is a theme to that, that there are differences. And there are certain kind of physical syndromes such as Reynaud syndrome, where people have really, really strong almost aversive response and vasoconstriction or blood flow reduction in cold to the point that it’s intensely painful in addition to just being cold. So there is certainly differences across people. And so yes, there are different shades. But I think, in general, I don’t think we kind of start our cycling careers as a cold weather writer or a hot weather, I think a lot of it does become experience and self selection after a while.

Trevor Connor  20:26

Yeah, one thing I remember you had in your book that I found really fascinating that I didn’t know was me, we all know that when you get into cold weather, your body’s trying to preserve heat, so it’s going to shut up blood flow to your extremities, and that’s why your hands and feet get cold. But as I remember, this isn’t true for everybody. But for some people that actually cycles. So it’ll you’ll shut off blood flow to your extremities for maybe 10 minutes, 15 minutes, and then your body will actually let some blood flow, go to the extremities to warm up for a bit for 510 minutes, and then go back to shutting down blood flow.


Yeah, that process is called code induced faisel dilation. And it’s, you can really look at it, if you think about kind of the body as an engineering design that, you know, when you first get cold, again, you want to preserve the heat in your torso and in your head in your center of your body. So it’s the body is basically saying, Well, I can live without blood flow in my hands, I can live without my fingers in my hands, I can live without my lungs, and heart and brain. So that’s where I’m going to prioritize the blood. But it’s almost as if the body use can be hedging its bets saying, Well, I can live without my fingers. But I don’t really want to. So every so often is going to, you know, give my give my fingers a little bit of blood just to try to maintain kind of prolong the time before it does become damaged from frostbite. So that’s kind of the teleological kind of engineering design perspective. But, you know, again, a lot of the research, including a lot of work in my lab is trying to see, you know, how does that actually happen? What are the mechanisms actually controlling their finger blood flow in the code? But yeah, it’s, I know, I think we’ve all had that experience that we go out on a on a ride, where we maybe didn’t wear kind of the right amount of gloves, in terms of coverage. And then it’s cold to start with. But as you start exercising, you get warm, you kind of feel this almost like cyclical blood flow in your hands, you suddenly after about 10 minutes or so it starts feeling warm again, and then maybe it gets cooled and it feels warm again, and that’s kind of the that cyclic vasodilation going on in your fingers.

Trevor Connor  22:51

So this is another one that you sent us we So just to give our listeners some background, we said we want to do the the myth. So I emailed you and said send us the miss that you’d really like to cover. And what I love and you sent this is there is no bad weather, just bad clothing equipment. And before you answer that, I’m going to say I always do my homework for these episodes. And here’s my commitment. A week ago, I was up at 9000 feet. It was 36 degrees Fahrenheit, about two degrees Celsius, and it started pouring rain on me. And I had to descend for 30 minutes, I am going to make the argument that was pretty crappy weather.

Chris Case  23:36

It was not that there’s no such thing as bad weather. There’s just Trevor’s bad decisions.

Trevor Connor  23:42

That to


what I really said that a question to you, Trevor, so you can get back on your cold weather soapbox from 35 so I was anticipating I can just shut up and you can just be talking for an hour.

Chris Case  23:59

Let’s recap that. That’s not having to go on for an hour.

Trevor Connor  24:02

My recap is it drives me nuts. The number of people who underdress


Yeah, for sure. It’s Yeah, I know this past weekend up here in Ontario was first warm, kind of real weekend day and and and that was nice and warm. And that was the first ride I did without without arm warmers or knee warmers. And this is now early May. Whereas even in late April when it was not that far above freezing, I was seeing people in shorts and cycling and go like oh, god no, but yeah, no, I really don’t think there’s an excuse to be kind of barring catastrophe like what you just had Trevor but most of the time there’s just no reason to, to be kind of ill equipped for weather. We have gotten so much better in terms of clothing design nowadays. Whether it’s you know, more waterproof yet kind of really, really good fitting clothing to, you know, having gear on a bike, much better fenders and things like that, that, you know, most of the time, you can be protected a lot more from from cold. So I think we we have expanded our ability to really tolerate cold weather and not so much hot weather. But certainly, I think we’re more talking about cold weather here. And we just have so much nicer equipment than you know, when I started riding in the 80s, where there was no specialized cycling clothing, it was like a big kind of garbage bag type of rain jacket, those kind of things. So, yeah, I think people really need to learn how to dress properly for, for cycling, and I would agree with you, Trevor, it’s, you know, you, you almost never go wrong with wearing a bit more clothing than what you think you need, rather than then too little. And always have back up, if you can, most of the time. Unless it’s really, really middle of summer, I’ll still have you know, a lightweight vest stuffed in my jersey pocket just in case of you know, it’s suddenly getting cold or anything like that. So I think there is definitely cases of bad weather. But I think a lot of it comes down to our poor management of foreign gear and our clothing choices.

Trevor Connor  26:34

Particularly if you do layers, you can always take layers off, but you have to have them first. Yep. And what I always tell athletes is because I whenever I tell people, you need to dress more I always get the Yeah, but what happens if I’m overdressed? What happens if I overheat a little And my response is always if you are overdressed, you’re a little uncomfortable. If you are underdressed, you are doing damage?


Yeah, absolutely. It’s, I think that’s a good philosophy to have. And I think we’ll talk about later on about you know, whether things like embrocation and stuff actually works is a physiological or is it really just, you know, kind of making your skin tingle, and you are definitely at much greater risk in the cold with with your joints, were just aggravating little things that you know, in a normal temperature or when you’re warm, wouldn’t aggravate you. But those those things just add up when you’re cold. And, you know, go go start your car in the middle of winter, you know, it’s not overly happy. So, that’s like your body and before it really gets warmed up or if you’re underdressed that’s exactly the same thing that’s going on your joints. Yep.

Trevor Connor  27:50

And I agree with you completely about the equipment. I have always been somebody who’s dumb enough to go out and ride when it’s negative 20 degrees. And I don’t need to say Celsius or Fahrenheit. I think that’s the point where the same It’s cold. It’s really cold. And I can tell you 1520 years ago, it was miserable. Mm hmm. Now I have the battery operated heated socks heated gloves heated jersey guy

Chris Case  28:15

over here

Trevor Connor  28:16

and you have nice face covering you have better clothing, you can go out and out weather and actually be quite comfortable.


Yeah, well this this winter and I can’t believe as a thermal physiologist, and as a cyclist for 35 years it’s taken me this long I finally invested in a good quality battery operated and operated insoles and I got to set a bar mitts for my bike and cycle. Why didn’t I do

Trevor Connor  28:42

I know what took me 20 plus years to do this. I just did the bar mitzvah this year and you could go out riding below Chris’s lap.


laughing at these two Canadians talking pharmacists.

Trevor Connor  28:57

pharmacists are great. Like I’ve gone out when it’s below freezing, and I don’t need gloves on.

Chris Case  29:02

Yeah, no, I don’t discount their effectiveness. It’s just funny to hear you guys talk about it. That’s I, I tend to reach a point where I think the wind chill of riding around on my bike when it’s negative 20 is I mean, I’d rather do something else. Right. So yeah, that’s all.

Trevor Connor  29:24

I since we’re talking about the Canadian thing, I will actually back what you’re saying that it’s it’s more cultural, because I will tell you growing up in Canada, I hated the cold. I didn’t enjoy skiing. I loved it when our family went down to Florida in the middle of the winter, and it was warm. It wasn’t until I moved to the US and everybody started making fun of me for being Canadian. And then I went well, I’ve got to play up to stereotypes and now I have to like the cold and at first it was an act that a certain point I went, Wow.

Chris Case  29:52

I don’t mind the cold and yeah, you can totally convince yourself well, not everybody but you can certainly try to convince you Some people can do a good job of it. Some people might not be able to do as good a job of it. But if you just embrace those things, whether it’s cold, whether it’s heat, whether it’s wind, there is a complete component that is psychological there. And it’s it’s not unlike the, quote, hard man, moniker or label that gets placed on people from Belgium because they like to ride in the rain in the nasty weather in the spring classics, etc, you embrace that, it becomes a routine, and so forth. And that can help, I can certainly help.

Trevor Connor  30:36

It’s also proving make buyers point that there is nothing more Canadian than a Canadian living in the US. We sat down with former professional triathlete Whitney Garcia, who is racing the heat of Kona on several occasions, so well as many other Ironman events in hot environments. We actually originally asked her for her tips about racing in the heat and the cold. But she was quick to point out that there’s such a thing as a hot weather writer or cold weather writer, she likes to heat

Chris Case  31:08

as someone who raced in Kona, which is traditionally PR can get a pretty warm Yeah. What were your strategies for dealing with the heat in a race? So I got that hot and you were out there for so long.


One strategy was was mentally reminding myself that I was very durable, because I would way rather hands down race in a hot race than a cold race. I’m just that’s a again, a tendency. I hate being cold. It affects me mentally to be cold and hot. so uncomfortable, but I can totally deal with it. So I would even pick races that would be hotter. Definitely versus cooler, colder races, knowing that it could be a strength of mine because mentally I was like I can Outlast I can now sweat. A lot of people that are going to melt because he is a real detriment to some athletes who are excellent athletes.

Chris Case  32:01

you thrive on challenge. Yeah, yeah, but


I want but don’t challenge me with a cold race because

Chris Case  32:07

only certain challenges. I don’t know. Very specific channel.


I can. Yeah, I


mean, generally, yes, I thrive on challenge. But there are some things like yeah, cold isn’t a good challenge for me. So so were there any things that you did in terms of dealing with the heat on the day? Being well hydrated is huge. And so that’s reason why I still carry water bottle, water bottle everywhere I go even when I’m not to have it. It’s a total habit to

Trevor Connor  32:33

stay hydrated. Was it as simple as just carrying around a water bottle? Or did you use pre hydration mixes? Did you use ice drinks during the race? Or beforehand? beforehand?


Yes, I mean, your Yes, your hydration for a big race like that. And a hot race like that starts before the day of the race. So you’re just don’t let yourself get dehydrated. You are walking around with a water bottle and I would didn’t really need to be consuming ice. At that point. I mean ISIS during the race to keep your core temperature down. But hydration and then yes, there’s lots of different mixes of things to keep your keep your sodium levels and what other

Trevor Connor  33:12

other levels? Did you ever use them?


Yeah, there’s Yes. And those were usually recommended by my coach because I didn’t get really deep into the nutrition of things. But there was certain things that were helpful, I mean, just straight water. For a waste, you’re going to sweat and lose a lot of salt in Oh, salt tablets as well. I didn’t even know about that at all before of my coach to like take tablets of salt and potassium and whether like there’s a there’s good combinations of electrolytes and so that B also became part of the nutrition of the race. And sometimes like for Kona, and for some other hot tuned human races, you would start taking those a day before you just extra salt your food. You’re banking it

Chris Case  33:53

Yeah, basically


you’re like you’re like saturating your body with water absorbing capabilities as best you can. I don’t know how good that is for blood pressure.

Trevor Connor  34:06

That is a different conversation. Yeah,

Chris Case  34:08

that that well who said triathlons were good for you.


That’s great. Nothing reasonable. Then during the race ice is key and so are like in Kona, they have sponges. They’ll say that the AIDS aid stations will have soaked cold water sponges and so you put them on like the back of your neck there are some key places keep your head and your neck cooler has you liver he release a lot of heat from your head. So

Chris Case  34:30

I get that there must be both physically and very mentally beneficial.


This the cold spongy ice. Yeah, definitely. I mean, every aid station it’s like a it’s like a mile. Usually what they’re per mile like corner they were and it’s like you just knock it down. It’s just that that account where’s my sponge? It’s one mile away. We’re slowing while my ice pack? Yeah. So but you put them under your arm like under your arms. You stick them like in your uterus. So you stick especially sponges because they can be stuck places. Yeah. So really the points of that are going to help stay cool is your neck your head likes to get under your hat, under your armpits or near though that and you’re growing so you’d see people language sponges. The other thing about Iron Man is so not glamorous like on the whole it’s a political sport. So hardcore, but like the nitty gritty is so disgusting.

Chris Case  35:22

Yeah, people are probably pooping and peeing all over themselves shoving things in weird places, knows what they’re doing out there and Kona.


So no comment.

Chris Case  35:33

No comment. That means yes.

Trevor Connor  35:34

And cycling the version is I stockings which is you get women’s nylon? Ice in them? Uh huh. And then you put them down the back of your shirt. Oh, I never saw that. And so that that’s really big. And I so I was managing a team we are at Joe Martin in in Arkansas. And we also have red bikes in the quickest way to repair pink damage is just by


Neil Ha Ha Ha, ha, ha.

Trevor Connor  36:04

So I’m in the middle of Arkansas at this grocery store buying a box of pantyhose and red nails. And the person at the checkout counter looks at this, then looks over sees my shaved legs. Yes, like


interesting. That’s a good story. That is a good story. Lucky walked out of that grocery store.

Trevor Connor  36:29

I saw the look on her face. And I was about to explain them just like that’s why


I’m not even gonna try.



Chris Case  36:40

Perhaps perhaps we should flip the tables around and talk about something that the Canadians don’t know all that much about which is heat. Okay, and some myths about the heat? Should we go there?

Trevor Connor  36:52

Let’s go there. We got a better Why not?

Chris Case  36:53

All right. first big myth about or question about heat? can we adapt to heat? Dr. Chung?


Absolutely, it’s probably the best thing you can do to get ready for competing in the heat is to become physiologically well adapted. And the body’s capacity is immense in his field in. And I know if you’ve gone over in previous episodes, but just to recap, the big things that happen to your body is that your new thermal regulate better, your heart rate becomes generally lower at any particular outage. And also you sweat a lot more you sweat earlier, and you are much more sensitive in the sweating response. So you so for a given hour, you might go from say sweating out, you know half a liter at this exercise to almost one liter you can double the amount of sweat that you can produce. So there’s there’s an immense capacity there. And one of the big tricks is what’s the best way to do it? And should you do it by exercising in the heat, or Can I just go sit in sauna for an hour a day. And the best thing to do from both kind of a physiological perspective and also from a time efficiency is to is to train in the heat is to find some way to get your body hotter than normal. And the easiest way to do that is through exercise. If you are gradually, gradually adapting yourself in the heat, it might take about a week and a half to maybe two weeks to become really well adapted. And that’s one thing you can do if you are say, a triathlete and getting ready for Kona in November or late October no November but you’re it’s already cool in the place that you’re training in. Well, what can you do there, you know, you can go indoors and be on a stationary bike and maybe have less fans and normal because then you’re going to become your bodies can become hotter. The other thing you can do is you can wear a lot more clothing, and in trap more heat in your body as you are writing. So there’s a lot of kind of both low tech ways you can do the heat adapt, and also higher tech ways. So you can certainly go in use my environmental chamber in my lab and exercise for for a prolonged period of time every day. 60 to 90 minutes a day for two weeks, you can you know go to a hot environment early and for two weeks beforehand become gradually adapted. So there’s a wide range of things you can do. But the end result is you’re going to be better. You’re going to have a little bit more blood and plasma volume. So you can distribute that blood kind of you have more blood to distribute and your body is also better at distributing it and also getting rid of heat sweating. So those are the big things? And does it actually work? Which is the brass tacks thing. Besides the physiology? Absolutely. In a meta analysis that I co authored in 2016, we looked at about 96 different studies from the 50s, up to the present day. And we found about 48 studies that were actually had a performance test, overheat adaptation before and afterwards, and we found that 46 of them had a significant improvement, the mean was about 8%, improvements through two through two, ranging up to about 20% improvement in terms of performance, in terms of exercising in the heat. So absolutely, that’s one of the best things you can do. And whether you are a an athlete, or whether you’re a worker, that’s going to be kind of knowing that you’re going to be working in a hot environment is to get your body adapted to it.

Chris Case  41:01

When you say gradual over a week and a half, two weeks, what does that What does gradual mean? Is that a five degree temperature increase each time, or is that a one degree temperature increase each time? Or is it a length of time,


it’s more length of time, the main thing I mean, your body doesn’t really, in a sense, know whether you are becoming hot because you’re exercising or because you’re sitting in a sauna on a slate, all it knows is that it’s hot, and that you better become better able to deal with it. So the main thing you want to do is to raise your body temperature about one and a half degrees or so, as a as a general rule of thumb for about 60 to 90 minutes a day for about two weeks to get kind of an optimal level of adaptation. So for example, if you are going to a warm environment and you’re gone two weeks ahead, what that means is that you should knowing the first few days, you’re not going to be able to ride as long or as hard as possible, and get yourself adapted to it, it’s the same thing as without the two, you’re not going to go to an altitude camp and immediately start going into full race prep and race type intervals or insurance, you’re going to gradually adapt to it. And but by the time, after about two weeks, in general, the studies show that your performance can reach about the same level as kind of as if you were in a cooler environment after about two weeks in the heat. So I think that’s the next question we’re going to talk about is that, you know, okay, we see all these improvements over time, both physiology and performance after let’s say two weeks in the heat. Yeah. Does that become a benefit? If I’m going to go back and, and, you know, my main race is actually in the cool environment. So should I actually heat adapt to as an ergogenic aid for a competition in the in the code. And the analogy is, you know, that’s exactly why athletes use altitude training. They’re not necessarily competing up at high altitude, but they’re competing back and sea level, they’re using altitude to have all these physiological changes there, that is going to make them better when they compete a sea level. So does that hold for heat? And the scientific kind of consensus is really equivocal right now there, there are some very well done studies that show that if you heat become heat adapted, and these were in trained individuals, after two weeks, and then you went and competed did a time trial in the in a normal kind of cooler environment. Some studies show that you, you do have an improvement. And you can actually perform better after this period of heat adaptation, even if you’re competing in a cooler environment. And then there are other studies that don’t show it. So kind of the scientific evidence is almost split right down the middle right now. But I guess my personal take on it is yes, the performance benefits, it’s kind of a 5050 right now, in terms of where science thinks it is. But the main thing is, for the large part, there is no harm in being heat adapted. It’s not as if you are not going to be able to compete as well. If you are heat adapted, so at at worst case, it is going to be neutral to your performance at best case is going to improve your performance and in a cooler environment. So if you if you can do it if you can integrate it into your yearly training plan. And then I would say, why not? Why wouldn’t you because again, at worst, it’s not going to help you at best it is going to help you. And so I know when I’ve been advising different Olympic athletes, and even if they’re not competing in the cold, we’ve been working with their sports science team to really integrate kind of heat adaptation, you know, on the chance that it is going to have an improvement. And again, worst case, it’s not going to harm them. So as long as it doesn’t cost them extra recovery time, it doesn’t impair their kind of training capacity, then it’s kind of a good thing to have in your quiver, just in case it does work.

Trevor Connor  45:47

So the only thing I’ll bring up to all of this is just also remember that heat exhaustion is heat exhaustion, do be careful with all these different things, don’t think, Oh, I’m going to a hot event in the heat and need to heat it up. So what I’m going to do is go into my apartment or home or bedroom, whatever, close all the windows jack, the heat up to 95 degrees and do a six hour ride on the trainer. And that’s going to get me ready, right? That can fatigue you that can heat stress you so as you said you want to build up to this. And the example I actually think is back in 2008, they were really concerned about the China Olympics because of how hot it was going to be. And they did exactly that they took a lot of the hopefuls and put them had them do a five day train, I think was a five day training camp where they’re doing six hours a day and they put them inside a heated trailer and had them ride on the trainer


at a national team. You’re saying some of the hopeful writers,

Trevor Connor  46:49

okay. I know some of them. And we were in this and just said that was just about the most miserable experience of my life. It practically burnt me out.

Chris Case  46:57

Yeah, yeah.


Not any anything comes down to elite athletics. There’s so many different priorities at play. And, you know, heat adaptation isn’t the only thing that you’re concerned with. There’s so many other things. So you have to very carefully integrate into it. And the worst thing to do is oh, you know, I heard this podcast thing I should be heat adapted and do exactly what you just said, Trevor. And you really need to ease into it, you need to have a long term view of what is happening and you need to kind of gradually build up to it rather than just immediately jumping in with with both feet, so to speak.

Chris Case  47:36

Yeah. In terms of overdoing it. That brings up the next question, in a way, do we shut down if our body temperature gets too high? Is there some protection built into our physiology? So?

Trevor Connor  47:51

And before you answer this, I have remembered reading, that there is a temperature where literally our bodies just shut down. As a matter of fact, there’s this older study that I’m looking at right now in the Journal of physiology for 1993. Where they said basically all the athletes they tested as soon as their core temperature hit 39.7. They, they all shut down.


Yeah, though, that was a classic study by Budo Nielsen in 93, from Copenhagen and, and that was actually also some work that I followed up with in for my PhD in Toronto at the military lab where we found the same thing we found that individuals, whether they were heated, adapted or not, whether they were well hydrated or dehydrated, they they seem to have a very consistent temperature at which they voluntarily stopped exercising, we, we asked them to keep walking, they were wearing chemical warfare clothing with the Canadian Forces, until they just weren’t willing to do it anymore. And we found regardless of hydration or acclamation status, there was a very consistent core temperature and this led to my paper in 98. And that between those two papers really instigated this whole idea that there was a critical internal temperature which our body shuts down. And, and there’s been a lot of controversy about it since and we can talk about it a little bit coming up. But uh, but the main thing is, do we shut down if our body temperature gets too high? Absolutely. You can’t fool kind of physiology in a sense. At a certain temperature your proteins are in your cells are just going to start breaking down. It is what happens when you cook an egg. Right, the protein changes shape and changes form. So the proteins in your body are no different. They’re optimized for working within a well within a very narrow range of temperatures and if it gets too high and again, I’m using Celsius here, because I’m Canadian. So you know, between 4041 and 42 degrees Celsius, that protein starts breaking down in your body. And that’s where you have irreversible damage to yourself. So there is an absolute limit, which you can’t go beyond. Now, the body has this thing called the brain, which is designed to ideally never allow you to get to that catastrophic point. So that’s where you start sensing, I’m really uncomfortable, I feel really hot. And you know, I’m, I’m not really having that much fun anymore, maybe I’m going to slow down, or maybe I’m going to stop. So your brain is your body’s best defense against kind of your, your physiology, or you taking yourself to that catastrophic limit. So that’s where in the early 2000s, as a response to this kind of critical internal temperature model, Tim Noakes in South Africa came up with this central governor idea of really where it’s your brain that is controlling your, your body and how hard it is willing to exercise. So the analogy I personally like to use it’s, it’s, you know, kind of your temperature system is kind of like a gas gauge, like your gas tank, eventually, you’re going to run out of out of gas, right. But before that happens, you start seeing this yellow warning light on your dashboard. And you know, where your brain comes in is really the comfort level of what you feel about driving with your yellow gas gauge light on, some people will immediately say, No, no, no, this is the end of the world, I need to find the next gas station now. Whereas other people are saying, Yeah, no, I mean, it’s still good, I can still keep driving for another, you know, whatever. You know, 30 minutes or whatever, it’s no big deal. And so that’s where your brain really comes in, you want your brain is trying to protect you ultimately, from running out of gas, but it’s trying to tell you in terms of temperature, in terms of your kind of substrate availability, how much kind of glucose and glycogen you have left in your body, how hard you’re breathing, all of these are signals telling your body How close are you to this catastrophic limit? And how hard Are you willing to, to kind of edge up to that line without going over? So you know, long answer to your question is that, yes, there is an absolute physical limit that you cannot go beyond. But most of the time, we’re well below that limit, because our brain is, is telling us, you know, telling us to slow down telling us to take a break, take a drink of water, whatever, all of these things to try to protect ourselves. And the best defense is the brain telling us Let’s slow down a bit.

Trevor Connor  53:02

It’s good to hear how the brain supposed to work is when that yellow light goes on. That’s my brains like, ooh, we’re having fun now.

Chris Case  53:11

Captain of bad decision.

Trevor Connor  53:13

What’s your feeling about this 2019 study looking at the 2016 UCI World Championships where they showed two of the women on the winning ttt team hit 41.5.


Yeah, it actually doesn’t really surprise me because even back in 2006, there was a nice study done looking at at half marathon in Singapore where they’re tracking record temperature. Throughout the race, I think they had about 18 kind of well trained runners, and they found that in these runners, and it took them about an hour and a half to two hours to finish. It was obviously Singapore, very warm, very humid, where it’s really challenging the thermal regulate, and within 30 minutes, most of them had to record temperature above 40 degrees Celsius, what were in the lab, I would have had to stop them because of athletes. And they were able to keep running at that high, high core temperature for the remaining hour, hour and a half and quite able and willing to tolerate that. So I think there’s a big benefit to being heat adapted and these individuals and also physically fit. And I think one of the other things that you do in terms of heat adaptation isn’t just the physiology is again the perception is that you become used to being uncomfortable when you are exercising when there’s sweat dripping down, off your face everywhere. When you feel like you’re you’re boiling on the inside and your body becomes habituated becomes sensitized to that And, and it’s not as uncomfortable anymore. And there’s was a really nice study again came out of my PhD lab in 2002, where they looked at, at fit individuals doing that walk to exhaustion with chemical warfare clothing compared to unfit individuals. And the unfit individuals had a really kind of close matching between their physiological strain and their perceived strain, how hard they felt things were how uncomfortable was the heat and everything. Whereas the highly fit individuals, they physiologically were just as stress, but perceptually, they didn’t feel nearly as stressed at all. So there was a big disconnect between that. So I think one of the things, fitness being fit and being adapted does is is a mental thing, it just gets you used to that discomfort. And I would argue, even just in forget temperature, just one of the things we do when we train isn’t just to benefit our physiology is to get used to riding hard, and that that feeling of your legs, burning that feeling of your, your breathing super rapidly, all of that. I mean, it’s it’s a huge psychological thing, in addition to physiology.

Trevor Connor  56:17

So to go with your analogy of the light, the the yellow lights coming on about the same time for everybody, but what you’re saying is in a very fit individual, they have a much better ability to just go Yeah, I’m gonna ignore that.


Yeah, absolutely. I mean, that’s, that’s where I think is going I think, at the same time, you know, there, again, there’s no difference in terms of a untrained or a trained individuals, not as their proteins will break down, one, one will break down at 40 degrees and other rule 43. You know, it’s simple thermodynamics physics, that’s going to break down that protein. But again, it is how close are you willing to push it. And that’s what I found in my 98 study, too, is that I also had low fit group and also a high fit group, and I found the low fit group stopped exercising at about point seven degree Celsius lower core temperature than the highly fit group. So I really think there is something to that. Being fit and being kind of adapted just allows you to, you know, mentally push harder or longer through a wall of discomfort.

Trevor Connor  57:27

It also sounds like you’re saying you’re dealing with literally denaturing of proteins, there is a certain temperature where no amount of training, no amount of willpower is going to deal with be able to get you past the fact that your body is not gonna be able to function.


Yeah, absolutely. It’s, you know, you are eventually going to succumb it’s, it’s, you know, it’s again, your brain telling you how close Am I willing to kind of step to that line. And and I guess that that goes to the other challenge is that if you are really fit, if you are edging very close to that line, yeah, it becomes a really a tightrope bath. And that’s where the really trained elite athletes can become at risk of heat exhaustion, because they’re willing to push themselves so close to the edge. So now if you have kind of interventions, such as you have a runner, or a cyclist who’s fit in, and already very hot and core temperature, but they pour cold water over their heads, and suddenly they feel Oh, I’m good again. My, my skin feels cool. So now I can go harder. Again, I don’t have to worry about that yellow light, you know, that’s where you run into the real, real problems of heat exhaustion and heat collapse is are those individuals that are already very, very close to running out of gas, you know, in that gas tank analogy.

Trevor Connor  58:57

So shall we move on to the next one, I want to introduce this one because you and I were at a granfondo in 2018. And you laughed at me for this. So I want to ask the question, or go for actually actually two questions here. So when you’re you’re racing or training in the heat, a is pouring water over your head actually work. And B is having a smoothie or some crushed ice before the race help.


Yeah, well, are you sure I wasn’t just laughing at you in general, Trevor?

Chris Case  59:28

Probably. Nice. Nice, good, good




Come on. It’s not only Americans laughing Canadians Canadians are allowed to make fun of Trevor too.

Chris Case  59:38

That’s true.

Trevor Connor  59:38

We make fun of ourselves.


Yes. You often do that, and then you apologize about it.

Trevor Connor  59:44

Yes, we do. And that’s the worst part.


But I’m probably I’m probably giving away a classic question of mine that I like to ask PhD students at their comprehensive exams, which is, you know, if you are, you know, doing this long bout of exercise, whether it’s a ride or a Run? Do you pour the water over your head and aid station? Or do you drink it? And I always find that intriguing question. I think, I think both work for different reasons. And pouring water over your head definitely does work because assuming it’s it’s relatively cool water, that it’s not tea that you’re pouring over your head. But the main thing that does is that it it for a short period of time it cools off your, your skin. And we also know that in terms of perceived effort, perceived discomfort, your facial and neck and head skin temperature has a really disproportionate impact compared to say pouring that water over your torso. So if I had, you know, one bottle of water, and I was told to pour it, where would I pour it on my body, I would pour it kind of gradually over my head and head in my face, because perceptually it is going to make the most impact. And because there’s so many more kind of thermal sensors in our face, and our head than there is again on our torso, and our arms are our legs. And so that’s where I would pour it

Chris Case  1:01:14

and like, it seems like that’s an instinctual thing to it’s not like anybody 50 years ago, maybe knew this, but you always saw people pouring water on their heads and faces. So


yeah, and just like a runner at an aid station, you’ve got those cool sponges where you can do it, you’re not gonna like rub it all over your, your leg, you’re gonna pour it over your, your neck, your if you have a running cap on, you’re probably going to put it under your cap, so that you have a continuous stream of, of water. And it’s just like with the socks, that you see some pros, you know, hanging out in the cars and sticking down your back, you know, that’s the next best thing to having it right around your neck and the head to really target the, the core, I don’t think those interventions are really cooling you down in terms of really having a thermal effect. But it is a huge perceptual benefit in terms of what you get out of it. And, and but again, the risk becomes if you are already on the edge of heat exhaustion, you’re very, very high core temperature. And now you suddenly feel transiently better. And you’re gonna keep pushing yourself hard. That’s where you can push yourself over the edge. But you know, as a, you know, assuming you’re still you know, far away from that critical catastrophic limit, then it is a good thing, because it’s going to make you feel better. Now, you know, the other thing is, just remember that if you are sweating, if it is the other benefit of having pouring water over your head or over the rest of your body is that you now have a wet skin that can essentially act as sweat on your body. If it evaporates and dissipates heat from your body, that’s also going to be an added benefit. So that’s why, you know, again, the other benefit, the physiological benefit for, for pouring water over your head or over your body is really, it’s kind of like free sweat. It’s instead of taking it out of your body, you are now putting kind of water all over your skin and allowing it to get rid of heat that way.

Trevor Connor  1:03:30

So I wish I had my old environmental extremes professor Dr. gottschall from Colorado State University here, because in our class, he told us Do not ever pour water over your body. And his reasoning was if you pour cold water over your body, it causes vasto constriction, which prevents blood from getting to the surface and releasing heat from your core. So it will actually heat up your core.


Yeah, no, that’s that’s also absolutely true. So if you had really ice cold water, that’s that’s not what I would do with it. I would you know, have kind of cool ish water, but you’re really walking that fine line. Ideally, you want to have your skin cool, but not so cold that you start vasoconstriction so it’s a constant game that that you’re playing. So again, I wouldn’t pour necessarily ice water over myself because yes, you’re going to start Bazell constructing, but I would pour kind of cool ish or kind of not not necessarily the super cold water coming out of the tap but kind of that medium type water just to really lower your skin temperature a little bit give you that perceptual benefit and also to have more water on your body that you can dissipate and evaporate for heat, heat loss.

Trevor Connor  1:04:58

Okay. So what about slushies? crushed dice, that sort of thing before an event?


Right? So So that’s my, that’s kind of the other half of the question that I asked PhD students is do you pour it over your head? Or do you drink it? So I guess before we talk about the for the race, let’s talk about if, again, if you have it, have that water bottle at an aid station again, do you drink it? Or do you pour it over your body, and the rationale for pouring for drinking it is especially if it’s colder, then it can kind of cool your body down a little bit, especially if it’s a crush dice. And also that it’s going to replace your your blood volume that you are losing through sweating. So that would be the rationale for for drinking and staying hydrated is that you are maintaining your plasma and your blood volume. So now, what is the rationale for slushies? Well, slushies is you know, is kind of ice in addition to water. So for a given volume, you can lose a lot more heat, or it can take in a lot more heat, because you have to turn that ice into liquid, so that melting of water from from freezing, but it’s solid ice to freezing, but it’s water, that already sucks up a huge amount of energy. And then to heat up that water. Once it’s melted, it takes more energy. So that’s why there’s a benefit to taking slushies. Compared to you know, just cold water is that you get much more for a given volume that you drink, or or eat with slushies. You can suck off a lot more heat from your body that way. But yes, they they have been used for pre cooling before quite successfully. And also, there are certainly some kind of bottles that are specifically meant to you know, almost have slushies in them that you can have on your bike and that you can kind of ingest as you were writing. And those certainly can be very effective because they have a huge capacity to take away heat from your body.

Trevor Connor  1:07:18

So I’m actually looking at that 2013 study by burden where they did the ice slushies and looked at the effect. And basically they said pretty much a deer saying that it creates this huge heat sink and in your gut. It can help keep you cool and help performance.


Yeah, I know my my students have been been kind of lobbying for a slushie machine and lab for at least the last few years now. And they claim it’s for science.

Chris Case  1:07:45

Yeah, yeah. This is making me back to my days as a kid when we would get something called a suicide, slush. Or we’d go to the slush puppy stand. This is the thing it was and we would ask them to put all of the flavors in at one time. You know, the squirt bottle things that that was probably just probably cancer is resting. Yeah, no, it well, it just kind of had that General. Sugar tastes.


Yeah. So anyways, I think you should get that for the students they appreciate they would appreciate it. I really can’t believe you know, 711 thousand marketed slurpees much more aggressively as a as a cooling aide.

Trevor Connor  1:08:32

I was missing out on the really hot days when I’m out for a long ride and I’m struggling. I will go to a 711 pick one of those up

Chris Case  1:08:41



Yeah, no. I mean, there’s there’s a lot of sugar in there. And there’s also I so Yeah, why not?

Trevor Connor  1:08:51

We caught up with Nick leagan. Shimano is road bread manager and former tech editor at velonews. Nick has had years of racing in extreme conditions, both hot and cold weather. And often for long periods of time. Nick shared with us a whole wealth of knowledge about how to deal with the heat.

Chris Case  1:09:07

So Nick, you’ve been in a lot of hot races before some that have been over really extended periods of time. Yeah. And I know you’re a thinker and you’re a tinkerer. So I’m curious, have curious, what innovations or methods have you devised to manage heat better under those conditions?



Nick Legan  1:09:36

First and foremost, you have to spend time ideally, in those conditions, and that’s why you hear about elite athletes training in saunas, things like that. I don’t have a sauna at my house. But I will say, keep an extra layer on that. Normally, I would take off to be a little more comfortable. So anytime you can, you can, you know, be specific in your training, specificity, the

Chris Case  1:09:55

conditions that you’re going to face specificity pays off, and of course, you

Nick Legan  1:09:58

also have to You can’t just go wearing extra jersey and not drink more you have to write just holistically to those conditions. I think that’s always helpful. So waiting until midday to go to your ride, if you’re expecting to be racing or performing in those conditions can be helpful as opposed to seeking out that early morning or evening cooler. Ice anytime you can get your hands on some ice, make sure you’re grabbing it on,

Chris Case  1:10:29

what do you do with that

Nick Legan  1:10:30

I sub supported events, I actually pre cut stockings to make ice socks.

Chris Case  1:10:34

Mm hmm. So look those down the back of your drawer Exactly.

Nick Legan  1:10:37

So I’ll have some of them in my hydration pack or a frame bag or pocket. And when I get to a convenience store, I’ll either buy a bag of ice or go to the soda machine and fill up one, not it and put it in the back of my jersey.

Chris Case  1:10:49

If you’re at it, tell me how refreshing that feels.

Nick Legan  1:10:54

I knew I was getting it’s kind of shocking to me actually shocking. You know, we’ve all had that. Taking our breath away if you’ve jumped into some cold water, but that I saw can do amazing things. If you got to be a little careful because you are also making yourself wet, which is good from an evaporative cooling perspective. But if it’s a really long race, wet plus shamy plus saddles, not always the best combo, yeah, you have to balance those things. It can be tricky. I know people that have filled I’ve actually in in a pinch. I’ve used a cycling cap and I filled it with ice and just put it down my jersey. Yep. So just you know a handful honestly just down your your jerseys gonna help if it’s a really long day covering up sunburn. But one thing I tell all my athletes and that I’ve been told over the years, and I wholeheartedly take it on board. sunburn is for amateurs. If you’re out there and you feel yourself getting crispy, address it, stop put on sunscreen, cover up, you know, sun sleeves, I wear when it’s hot. It’s it’s counter intuitive, but I’ll wear a buff. I’ll cover my ears. I mean, and we’re talking some alter events where you’re out there for hours and hours now, yes. If you’re racing to crit, and it’s really hot, and you don’t want to race around a buff. That would be funny. It would be Yeah, he looked interesting. But yeah, there are lots of ways to deal with heat. I think honestly, you can also the power of the mind is incredible. And trying not to focus on it or trying to just think, you know, I’ve seen people really well melt when they have a hot day and a headwind. But the truth of it is that headwind is actually cooling you move that through through the power of evaporative cooling. So embrace that headwind and take it on board and and recognize that it’s actually a friend right now. And it’s actually going to hurt you more. When you have a tailwind, you’re going to be even hotter. Yeah. So any little kind of mental trick, visualization can be really helpful as well visualize something more comfortable, something cooler. Yeah, there are lots of things you can do there.

Chris Case  1:12:51

And what about equipment? Are there things that you can do to improve your experience when it comes to your equipment in super hot conditions?

Nick Legan  1:13:02

Well, one, one great example is insulated water bottles, Mm hmm. That will keep it cooler, at least a little bit longer. If it’s if it’s 100 plus degrees Fahrenheit, those are going to still they’re still gonna get warm. But you know, using something like that can be helpful. Absolutely. A helmet that’s ventilated, maybe that’s the day you don’t wear the arrow lid, you know, write really lightweight jerseys, get rid of the base layer, things like that, it again, this comes down to priorities. But if we’re looking at optimal performance and these conditions, will performance is not really often directly correlated with comfort. So it might be less comfortable. Some people love a base layer because it’s comfortable, I keep seems away from the body, etc. But if you really want to go fast in those conditions, well, it’s not about comfort anymore. It’s about going fast. So get rid of the base layer, inner socks. shoe that has more drill holes in your shoe. You know, get some ventilation, pour some water down there.

Chris Case  1:13:52

I know when your wife raced dirty Kansa one year you even planned ahead to have different helmet for her and some other things when the so dirty Kansa you start and the temperatures are cool and it’s it’s not the sun hasn’t even risen it, you know, high in the sky yet. So you can get away with an aerodynamic helmet, some aerodynamic equipment that would be hot. If it was in the middle of the day. Yeah. And you get to the aid station and you switch out into some gear that allows you to cool off more. So you thinking ahead like that for some of these ultra events is also part of the game.

Nick Legan  1:14:30

Absolutely. I mean, we went I wouldn’t say we went overboard because it paid off. She had a great result. She podiumed she started in an aero helmet. she rode midday in a ventilated helmet. And then she switched actually a third helmet that had her light pre installed Well, in case something went sideways. She didn’t even have to fumble with her light. Yep, she was we did different pre pre packed hydration packs. Except that for the hottest part of the day. She didn’t wear a hydration pack. Mm hmm. Because

Chris Case  1:14:57

Yeah, that was a cool little bit zactly

Nick Legan  1:14:59

And we’ve very much she had a really good plan on, I’m going to hydrate and eat early while my gut still works so that when it gets hot and I, and I can’t get those calories on board, I’ll be okay. Mm hmm. You know, and I can maybe make it up a little later in the day when it cools off. So absolutely thinking about it. Again, holistically, you know, what’s the entire experience going to be like? And where can I get the things in that I need? When my body is ready to take them on board? Yeah, it’s helpful. In terms of other equipment, I mean, you could we could talk about chain lube, and things like that. But yeah, someone’s just gonna come down to experimentation.

Chris Case  1:15:38

Yeah, right. Hmm. Cool.

Trevor Connor  1:15:41

Let’s get back to our myths about heat.

Chris Case  1:15:45

Next on the list is sweat. So if sweat drips off of us, is it losing its power to work for us do wicking undershirts really work? So that’s a two part question for you.


Yep, so first off, sweat dripping off, you absolutely does not help at all. All it does is getting you dehydrated faster. So you may be riding indoors, if you’re kind of stuck indoors, and you see this big, massive pile of sweat and say, Oh, that was a great workout? Well, no, it means you, you’re probably overheating because all of that sweat on the floor hasn’t done a bit to help you actually lose heat. So. So no, you don’t want to be toggling off sweat, you don’t want to be the, you know, kind of having a trip off of you. That doesn’t help at all. Now, what does a wicking undershirt do? The wicking undershirt moves the water away from your from your skin a little bit. And then to end, the main benefit of that is comfort, because having a really wet skin feels really uncomfortable. So the main purpose of a wicking undershirt is to move the water just that little bit above your skin into the into the base layer itself. And then you are still having that wet undershirt. And it is still evaporating as sweat. But But the main benefit is that it is making you a little bit more comfortable than if that sweat was just all over your body.

Trevor Connor  1:17:27

And so we haven’t mentioned this yet. And it’s probably worth mentioning for anybody who’s asking when you’re talking about sweat and the benefits to cooling you down. It’s not the production of the sweat itself. It’s you get the sweat on the surface of your skin and then heat is dissipated by evaporating that fluid. So if there’s no evaporation, there’s no benefit.


Yeah, absolutely. It’s the only purpose for the sweat is if it is if your body then heats it up and turns it from liquid into water vapor. And that sucks away a lot of heat. So if it drips on the floor, well, obviously it is not taking heat away from your body.

Chris Case  1:18:06

Yeah, it’s lost its opportunity to do the job it was intended to do. Mm hmm. Yeah.

Trevor Connor  1:18:11

I think I’ve told this story before but I used to run a morning. gym. You have to for trainer class. We had a guy there. So apologize. I just I feel a need to tell it. Please, we had a guy that had such a huge sweat puddle. Yuck. underneath him. Let’s just say my job at the end of the class was to do the mopping.

Chris Case  1:18:39

Was he proud of this puddle? I think so. Yeah. I bet he was

Trevor Connor  1:18:43

that moment of going at it with the mop. Talk about you haven’t you have a moment in your life where you just go? What am I doing with my life? That was your moment? That was my moment. And after that what did you did you quit the job

Chris Case  1:18:59

just right then

Trevor Connor  1:19:00

Nope, I just had that moment.


And then Trevor just repressed his his his existential crisis and just stayed working there for another five years right


yeah, pretty much

Trevor Connor  1:19:12

it’s amazing what I can push down. Okay, so along with that should our drink mixes match our sweat composition and there are now drinks out there that are big on this. We will analyze your sweat and then give you a formula that has electrolyte composition similar to what you are sweating out.

Chris Case  1:19:35

Custom drink mix.


Yeah, I think the first thing to keep in mind is that you know from the early days of Gatorade has been talking about replacing your electrolytes as you sweat. Well, the thing to keep in mind is that every single sport drink out there except for some of these newer ones is still has much less electrolyte salt content than your sweat. Because if you actually tried to mix a drink with the same salinity, same same salt concentration as your sweat, it is just horrible. It is just impossible to mask with any amount of sugar, so or sweeteners. So most of the time when we are taking in a sport electrolyte drink, it is still what we call hypo tonic, it is much less salt than what you are sweating out. So, so don’t ever think that you know, we are replacing all of the salt.

Chris Case  1:20:32

What about what about licking your arm? And just tell me you haven’t tried cycling, so to speak.


I guess Trevor could just like instead of mopping up the floor, sweating in a water bottle. And there’s this next drink. Oh,

Trevor Connor  1:20:49

gosh, oh, that’s that just yeah, I’m considering my life once again.

Chris Case  1:20:57

Hey, you put some fancy fancy marketing on that product, you might actually get rich.


Yeah, but I guess that’s the big message to to raise is that almost all of the drinks out there is still much less salty then then the sweat that we’re losing. So you are always going to be at a net loss of, of salt from your body when you are exercising. Most of the time, that’s not a big deal, because we have so much salt in our diet that we can easily replace it. But if you find that you are a very, very salty sweater, and lot of the times you can just see if you are super salty. If you have at the end of a ride you you find just sweat stains or salt stains all over your clothes that might be assigned, you might want to experiment with a little bit more more salt content in your in your drinks. But I don’t think you actually need to match your sweat concentration competence in your drink, you want to if you are a very salty sweater, and I know you’ve had a had an episode on cramps before, one of the potential theories, it’s not definitive is related to electrolyte loss, but for cramps, and if you are prone to it, you might want to try supplementing your drink with more than normal salt or having a saltier type of drink. And just really trial and error. See how how you feel. I always say, though, the you know, the best drink in the world is completely useless unless you’re willing to drink it. So you know, you also have to match it with your own taste preference too. And and again, try it before a competition,

Trevor Connor  1:22:46

you brought up a really important point, which is people are very concerned about electrolyte loss, but our bodies can actually tolerate a pretty significant electrolyte loss and still function completely normally. But what is often not brought up is the importance and the ability to absorb. So if you made a drink that’s got a heavy quantity of electrolytes in it and consume that. Well your body likes to maintain what’s called osmotic pressure, which is the balance between the fluid and the electrolytes and at the concentration, the electrolytes in the fluid. So if you hit your gut with that electrolyte bomb, basically, your body’s going to draw a fluid out of your blood into your gut to dilute those electrolytes. So you can actually sort of the hydrate. Mm hmm.


Yeah, absolutely. And that’s why you shouldn’t be drinking seawater if you’re stranded on life raft, right? It’s because it is, it is has so much salt in it that it’s actually going to suck away your the fluid and the water that’s in your cells to try to dilute it.

Chris Case  1:23:56

Let’s hit you with one last question. Dr. Chung, and that is, does a mouthwash or a menthol rinse or any of these things help when it comes to dealing with the heat?


Yeah, that’s that’s been a really kind of new and exciting area of interest probably over the last decade or so in terms of how does mental work as an ergogenic aid, especially in a temperature aspect, and the first off what is mental it’s really kind of the active ingredient in mint, right? It’s that kind of a tingly sense that you have when you have your drink, drink anything with mint in it or, or have a, you know, gum with peppermint or anything like that. So, the idea is that if you either spread a menthol kind of gel or or in just a very dilute solution of mental that it is activating the same kind of cool sensors and cold receptors in your skin. in your mouth and oral cavity that that responds the exact same as if you were cold, the cold receptors fire, and you get that sensation of cooling even though there is absolutely no change in your temperature. So the idea is, is really a perceptual one, it is making yours, your body or your skin feel that it is cooler. And again, we talked about the perceptual benefits of that. So, there have been kind of consensus statement actually is coming out soon in sports medicine journal, I know because I was a peer reviewer for it. And I quite liked the the overall review. And the consensus is that for a lot of kind of activities that can work, it does give that transient feel of being cooler than normal. And that can allow you to again, reset that perceptual willingness to exercise. So, yes, the studies have been with rinsing with with a menthol solution, or else using some kind of a menthol type gel over your your body and some studies have looked at it on the chest, others looked at it on kind of the face and the head and neck area. And overall, it’s generally effective. But again, the way it works is that it activates those exact same cold receptors as if your skin was cold and give you that feeling of being cooler than normal. And then that provides you with that perceptual cue that you can still be working hard. That 2013 study I mentioned earlier. So here’s the title of it. Here’s an interesting mix. The effects, the effect of ice slushy ingestion and mouthwash on thermoregulation and endurance performance in the heat. And they remember said pretty much what you just said, which is it’s completely Well, they did say what the slushy Yes, there was actually a cooling effect created a heat sink. With the mouthwash it was completely sensor. So it could help performance because you believe that you are cooler. But there was no actual cooling effect. And I believe they said, so you do have to be careful, because if you are starting to suffer from some form of heatstroke, this can convince you that you are better regulated and heat than you are right. Right. Yeah, absolutely.

Chris Case  1:27:29

Well, on the theme of cold and feeling cold, should we jump into the cold myths? Now, back to familiar territory for you guys? Ah, let’s ask Let’s ask the first question. as it pertains to cold as we did with heat, can we adapt to cold?


it it’s much harder to adapt the cold or body, you know, we evolved from from a very kind of warm weather ancestors. So the capacity to adapt the code is relatively minimal to almost none in terms of physiology compared to heat. But I think it comes down to most of the adaptation is perceptual, that, you know, we’re just become desensitized to cold. And you can see this at play, you can. I know, again, we’ve talked about some of the studies I’ve done looking at cold response in the hands and blood flow. Well, if you stick your hand in cold water, the first minute or two, it’s really, really uncomfortable. But then after a while, it’s not as if your skin temperature has gotten any warmer, but it doesn’t feel as bad. So a lot of it is that perceptual, just like if you jump into a cold Lake, the first couple of minutes are really really uncomfortable. Then after a while, you know, you become sensitized to it, the skin receptors that the cold receptors in your skin are still firing the same amount, but it’s your brain tuning down that signals saying oh, okay, it’s not that big a deal after all. But there, there is some kind of long term adaptation to cold there is but in terms of your metabolism and everything, but it is really, really minor. And in terms of a performance standpoint, it’s not really kind of significant as it is with with heat. So overall, there is some kind of minor physiological adaptation, but it is nowhere near the amount that we can adapt in terms of what we’re able to in the heat.

Chris Case  1:29:40

So if somebody was preparing for the idea bike, or some long race in Alaska, there, there wouldn’t really be a benefit to going into a cold chamber and except for the psychological benefits, there wouldn’t be a physiological benefit here too. prepping in that way,


yeah, there be very, very minor but it’s not as if the case that you know, your substrate metabolism is going to change lock stock and barrel or your your muscles become adapted to being able to fire when even the same strength even when it’s cold, there’s there’s nothing like that equivalent to the lower heart rate that you see with heat, or the lower core temperature or the higher sweat rate. So again, I’m I’m convinced the vast majority of any of that benefit is more perceptual than any thing physiological.

Trevor Connor  1:30:41

Okay, so you sent one to us, that is a great one that I was embarrassed, I didn’t even think to put on the list, can you damage your lungs riding in the cold,


I would say right off the bat that no you you can’t really damage your lungs, cuz there actually have been studies and where they have had individuals exercising, breathing gas that is as cold as I think minus 25 degrees Celsius. And they measured they also put a temperature sensor kind of down your airway, and in in your trachea and into kind of the upper part of your your lung kind of beds. And what they found was that even with breathing through the mouth, you Your body is so good at at warming your D inspired air, that by the time it gets to your your actual sensitive tissue in your lungs, it is pretty much at room or air or sorry, your body temperature already. So and that’s even with breathing gas that is minus 25 degrees Celsius, so we’re talking, you know, 60 degrees colder than then your body temperature, so your body is extremely effective at at protecting yourself. So you’re not going to damage the actual alveoli or the actual really kind of thin, sensitive air exchange kind of beds in your lungs from breathing cold air, so you don’t have to worry about that. On the other hand it is it can be uncomfortable. So one of the things you can do is you know, in the wintertime, I often wear a Bof neck warmer and I just have that over my my mouth just to slow down the airflow a little bit. So can you actually damage your your lung tissue? No, but so don’t worry about it. Keep in mind that you also have cross country skiers who are competing also sometimes in extreme cold and breathing huge amounts of air and they’re their lungs aren’t damaged either. So don’t really worry about that if it feels uncomfortable, you know, wear a bandana, wear a buff and just to kind of slow down their air and also to warm up some of that exhale there. The other thing to keep in mind though, when you’re in the cold Is that you, you can still lose a lot of moisture and water from your body and also heat from breathing because again, if we’re breathing in minus 25 degree air that is 60 degrees colder than your body and you know you are now breathing out all of that, that air that you have now warmed up and you’re losing that heat and you are also humidifying that air so that it again doesn’t damage your lungs with dry air. So you are also losing that water also. So you still need to keep in mind that you can still lose a lot of heat and also water through breathing when you are exercising in the cold. And that’s especially dramatic when you you can just see it right when you breathe out and you have that big huge mist coming out of your out of your mouth. That’s all water vapor, right? That is all water, warm water vapor that is now kind of being lost in your body.

Trevor Connor  1:34:18

Another thing worth pointing out that you wrote extensively about in your book is that it can be difficult for asthmatic.


Yeah, that’s the huge kind of caveat if you have sensitivities such as asthma or exercise induced Bronco, Bronco construction, that breathing in of cold air oftentimes is a big trigger for that. So, you know, that is one population that really needs to keep that in mind that if you are troubled by it and one of the things you can do is to warm up much more gradually. And you know, don’t just immediately go in and start doing intervals and breathing. Huge, huge amounts of air. And, you know, start by really gradually warming up maybe if you can warm up indoors, so you really kind of warm up that whole respiratory system of yours. And then even once you get outdoors, continue that gradual warm up before pushing yourself really hard and, and sucking in a lot of air at once. So now

Trevor Connor  1:35:23

we get to my soapbox to know there’s much more to cover. But is it better to be overdressed or underdressed? And let’s answer that question both for training and for racing. And you know where I stand?


Yeah, I would certainly agree with you that it’s much better in training and most of the time in racing to, to overdressed than underdressed, I know, again, I tend to be horrible in the cold in terms of again, when it’s just that above freezing, you know, those early spring races? And unless I’m really overdressed? Yeah, I’m going to be much worse, worse off, because I just can’t feel my feet, I can push as hard because my muscles aren’t, aren’t warm. So I’m definitely with you in terms of training, I would, I would if, if there’s any doubt, again, it almost will never hurt to wear one more layer of clothing than you think you need. Whereas wearing one less layer can be really bad news. Again, not only in terms of discomfort, but also like you say Trevor damage, especially when we’re talking about your knees and your leg muscles. And then in racing. Again, it it really depends on personal preference, and how much does you know having that knee warmer bother you or not? I think again, if if push comes to shove, I would rather wear wear those knee warmers then than not if I had any doubt in my mind. And yeah, so I mean, I largely agree with you in terms of of your stance on that too.

Trevor Connor  1:37:12

And I am right now looking at notes from a whole bunch of studies showing that it can cause muscle tearing, it could cause damage, it reduces performance, we’ll put all those references up. But I think the title of this one study from 2016 says it all just title as increased risk of muscle tears below physiological temperature ranges.


Yeah, absolutely. And again, he is think of certainly, you know, if you think of you’re going to go to the gym, and you’re going to try to do a world record squat, right? Are you going to do it in a really cold room? Are you going to do it in a warm room, you know, are you going to do a warm up beforehand or not. And you know, most of the time, I would think most sane people would do a warm up and would choose a warm environment to do that. And then and it is just protecting your muscles from all that micro damage that you can’t necessarily see. But it is there. And it is happening.

Chris Case  1:38:12

From my point of view, too, there is a maybe a psychological component here in that I feel like I’m a colder person. And I will dress with many layers relative to other people that I’m riding with. But I feel like I’ve gotten used to not maybe it’s called being uncomfortable, but just that you sweat a little bit more, but then you get used to that type feeling that comes with maybe over dressing versus under dressing and I have chosen that and I prefer and I’ve gotten used to it. So there’s that too.


Yeah, I think I think it’s one of those things, you get used to it in training and it’s not that big of a bother again, having that pair of knee warmers on in a race, right.

Trevor Connor  1:39:02

The one thing that has been brought up that I feel is the one legitimate counter argument I’ve heard is let’s say you’re somewhere where there’s mountains, and it’s a cold day and you go climbing and you got a lot of layers on you’re gonna sweat a lot share and then and then you turn around and you come down and now you’re getting all that wind chill evaporative cooling on wet clothing and it can really get you cold. So I do when I’m climbing in the mountains on a cold day, I will unzip a bit so I don’t sweat a ton. And then immediately zip everything back up as soon as I get to

Chris Case  1:39:34

the top. Yeah, I mean the the clothing. As you mentioned, Dr. Chung has come a really long way. But there the onus is on the individual using that good clothing to also thermo regulate to some degree. So they’re not drenched at the top of an example like Trevor’s mentioned.


Yeah, absolutely. And polar explorers and polar adventures. No, the worst thing you can do is to sweat and saturate your clothing because that’s going to cool you off. That’s gonna also eliminate kind of the thermal properties of the clothing that you’re wearing if it is soaked in water. So, yes, absolutely, if you’re going to be doing a lot of if you’re, you know, in the mountains and doing climbs and descends climb and the sense, absolutely whether, you know, take off some layers or unzip on the climb up, because you’re gonna be generating a lot of heat. And also, you’re not going to be going that fast, so you’re not going to get a huge amount of convective cooling, and then at the top, then you can put on that dry clothing again, I think that’s a, that’s definitely the best plan to have. Because the very worst thing is to be to be wearing really saturated, sweated clothing and then hitting a big descent or, or things like that, because you’re going to have so much extra heat loss and the, again, the that thermal garment is going to work nearly as well when it’s soaking wet compared to when it’s dry.

Chris Case  1:41:00

embrocation This is what I’m, I’m I like to ask because as someone who does a lot of cyclocross, I tend to see the people rubbing embrocation on their legs frantically before races on cold days, and I just shake my head at them. So Dr. Chung, does embrocation really work?


Yeah, I’m completely with you. I love cyclocross, too. And I you know, there’s nothing in a sense that beats the smell of kind of embro to kind of get you all psyched for racing. But the active ingredient in embrocation is capsaicin, it’s the same as you know, when you eat really spicy food. So, what does that actually do? It is kind of the opposite of menthol, instead of activating your yours cold receptors, it is activating your heat receptors. Now, again, it is not actually physically warming you up, it is activating those skin receptors and for heat and fooling you into thinking that you are warm when again, you are not. So you can look at it as the exact opposite of mental it is all perceptual and there is no physiological change in your body. So you are going to be just as your skin is going to be just as cold, but you may not feel it. And you can get that damage that we’ve been talking about, even though you feel that you are warm. Absolutely. The invocation, you know, smells great gets you really psyched up. It’s intrinsically kind of embedded into the sport of cycling. But does it actually warm up your muscles in any way, shape or form? No,

Trevor Connor  1:42:45

I’ll actually add that embrocation also promotes vasodilation at the skin or just below the skin. Which means when it’s cold outside, you are getting blood flow to your scan, which means you’re going to be releasing heat, which is the exact opposite of what you


Yeah, and but again, it is it definitely doesn’t penetrate down to the muscles. So it is not as if it is causing greater circulation in your muscles and improving blood flow there.

Chris Case  1:43:20

But it smells good. does smell good.

Trevor Connor  1:43:22

This is no longer the case. But important thing to remember is a lot of amateurs have seen pros on really cold days out in just a jersey and shorts, putting the embro on and racing that way and go well the pros do we got to do it. There was intelligence a few years back a UCI rule that you are not allowed to use knee and arm warmers. So they had no choice.


Right? You got those little heating plasters that you see look like big band aids that are being put right on the front of their knee under their kind of kneecap still protected patellar tendon. So yeah, you have you do see those kind of things to

Trevor Connor  1:44:03

Nick league and also had a lot to say about riding and racing in the cold. Let’s hear suggestions.

Chris Case  1:44:09

Tell us a little bit more about how you manage your body temperature and the conditions when it was cold like that.

Nick Legan  1:44:18

Yeah, I mean full disclaimer. It’s not like I’ve done the I did Roger Invitational trail Invitational. Yeah, those those athletes are doing something really. I mean, some of the stuff people don’t mean extreme it is and I haven’t done a lot I do fat bike. I do have some of that that experience, but not to that extent. Yeah. So I guess I’m on the saner end of this spectrum. Um, but I certainly you know, ridden in snow and rain and sleet for hours on end. And it can be really mentally tough. But I’ve also found that a friend of mine CEO says there’s no bad weather. There’s only bad clothing right? You know, I’ve heard that or bad preparation. Yeah.

Chris Case  1:45:00

So having having the rounds like something a Boy Scout might say,

Nick Legan  1:45:03

yeah, we’ll always be prepared. Yeah, yeah. I was Boy Scout, it’s probably not news to you know, you’re

Chris Case  1:45:09

a thinker man. Yeah.

Nick Legan  1:45:12

But yeah, there, I found that there are certain there’s some for me. And again, I think everyone’s experience is unique. But for me, I’ve definitely found some key pieces of clothing have made a real difference for me. So a few of them. Obviously, headgear is important. You want it to be warm without being too hot, because then you can when it’s cold, you want to try not to be wet. Yeah. It’s kind of the opposite of when you’re hot away. Yes. But it’s for the same reason. It’s evaporative cooling Exactly. If you can, for instance, you and I’ve done a ride before, and I’m gonna call you out a little bit where you don’t take layers off on the climb, and you just get to the top and you’re soaked, and then we descend and we’re cold. No, maybe you don’t do that every time. I hope not. No. But um, but it’s important. You know, when you’re when you’re starting that climb on a cold day that you take off that jacket and you maybe start that climb a little cold, so that you can do the whole climate that having stopped a bunch to into, you know, Don or doff layers. I love a buff. I’m really like, I’m talking like a neck Gator. Yeah, I think a buffet buffet is a brand of them. Yes, you can take it off for the climb, you throw it back on, you can pull it over your face for the center up and over your ears. They’re just really versatile. You can use that as a headband and ear band hat. Those are really, really, really great for me. And I typically carry more than one of them, too, so that if one does get wet, I put it in a pocket and I pull it dry one out. If you’re going to be out there for a really long time even bringing a spare base layer can be really helpful. And again, just getting dry. I almost always have a vest and a jacket. Because they they do different things. One thing I was actually, I don’t mean to name drop, but I’m going to do that I was hanging out with Taylor Finney the other day. And we were talking about how we love all the bike packing bags just for training. Because you can throw a puffy jacket and rain pants in the yes and bigger booties for your shoes, some dry socks, things like that. And how that is just like wow training is so much more pleasant. Now when you’re dry when you can bring the things you actually need instead of suffering through a long ride and sort of like shivering maybe a little I think of those bike packing bags is your very own personal follow car, your little closet. Yeah, it’s a rolling closet and linen closet, but doesn’t make a big difference. You know, I oftentimes in winter will have to plug Shimano, we do make a winter boot like a gore tex waterproof boot that’s insulated. That really helps in the shoulder seasons. Even if it’s just kind of wet out that can be really helpful. But I think another thing to to recognize is if you’re if you’re into the ultra thing, and I think a lot of my advice skews that way because that’s the scene I’m in yes recently. But bigger shoes, the normal, right? The same shoe that you normally ride but maybe half size or size up, lets you put in thicker socks, and or even thicker socks. And this is ghetto. But trash bags, you know, like like the grocery bag vapor barrier. Exactly. It’s a vapor barrier. And if you don’t know what a vapor barrier is, Google it. But the whole principle is though, it’s better to be warm and wet than cold and dry. And, and that’s what it does. And it’s very effective. As long as you don’t then take it off. You got to kind of stick with it. But the vapor barrier is really really helpful. Especially on your feet. For hand I mean it’s extremities, but a lot of people suffer with so your feet that’s one way to go for your hands. I find I love a wool glove liner defeat makes one that is my favorite because it also has that electronic you could still use it on and still Instagram. They’re cheap. They are they’re Yeah, they’re great. And then I’ve actually I don’t own a motorcycle anymore. But I have in the past I’ve been running these gauntlets like a lobster style, right rain mitt, and with just the rain mitt, and the defeat will glove liner. I’m pretty comfortable, even if it’s snowing down to 25 degrees. So that’s kind of my bike pack race setup. And that’s all the gloves like I carry. So the idea being you’ve got something that works in it insulates even when it’s wet. Well, and then you’ve got a layer that keeps the wind and the wet off. So you’re that much warmer. Yeah. So little things like that can can go a long way.

Chris Case  1:49:17

Are there any things that you would recommend for equipment when it comes to riding and racing and really cold weather? Do people need to be careful with their equipment? Because it’s more brittle and super cold temperatures?

Nick Legan  1:49:32

Yeah, especially if you’re talking about plastic things. I mean, I wouldn’t worry about carbon fiber like your frame is fine. Yeah. But if you’re looking at like little plastic accessories, like like a Garmin mount or GPS mount some of those if you’re in really really cold temps. Absolutely not that you should lean on that amount anyway, but But yeah, yeah, we’ll make some things brittle. equipment that’s really made a big difference for me a pogies. If you know what those are. No, I don’t a pogi is it’s developed for I think actually it came in like skiing or maybe dog sledding or something. But basically it goes over varmints makes them, like over your controls your bike, so they’ll make him for flat bars, they’ll make it for drop bars. And it’s basically creates this little pocket around your shifter and brake lever. And then you put your hand in there. And if you’re writing, writing and really cold temps, it’s it. I hate the term game changer, but it is like you suddenly can ride. Yeah, and I really think glove, that can be really helpful. There’s a lot of really great winter Boot Options. One thing I would also say is a wet lube on your chain, run a wet lube. And when it’s cold out, you want something that is actually penetrating and some would argue that you should run a wet lube all the time, because that’s what’s actually penetrating the rollers and pins of your chain better than a dry lube. But when it’s cold out, it’s often times sloppy out too. Right. So yep. stopping to lube, your chain is cold. So the other thing is even stopping to change a flat is cold. So maybe running before your tire. Yes, absolutely. Because a flat tire in winter is now you don’t want to do that.

Chris Case  1:51:05

Yeah, yeah. Next one, let’s see, if you had one extra piece of clothing on you and you’re freezing cold? Where would you put it on your head, on your hands on your feet, or your core excuses.

Trevor Connor  1:51:23

vj Chris.


This is probably about the time that I turn around and go home about to make that choice. There’s no there’s no real kind of one ideal. I mean, ideally, you would have have your head protected, you would have your hands and feet protected too. I know that’s a big issue with me, I need to me, I need to make sure I usually wear much thicker gloves than my wife when we go to ride together. And she always just looks at me like I’m demented. But I know I have real real trouble with my hands. So if I have one choice, I would probably pick my hands. But I think I also like I have this bell helmet from a few years back that star kind of helmet with the arrow, arrow kind of switched it, you can just close the vents. And I love that that helmet for these spring and fall days because I can still you know kind of be be relatively warm in it. And then if I do really warm up, then I can just open up the vents. But yeah, if I had one piece of clothing to pick that is warmer than normal, I would pick my hands because I know personally I’m really sensitive to that. And also if I can’t shift their break, then I become a hazard to myself.

Chris Case  1:52:52

That’s true. It’s very true. So

Trevor Connor  1:52:54

I was always very much on the protect the extremities. But actually a really interesting point in your textbook was the fact if you think about it when the extremities get really cold that’s because your body’s no longer sending blood to the extremities in order to protect the core. And if you wear clothing to keep the core warm, your body is going to be more willing to allow blood flow to the extremities. So in reality it’s you really should be doing both


Yeah, there was a nice kind of study by my lab mate and during my PhD also at the military lab which was looking at you know, in a sense that exact question if you had a particular amount of heat that you can put to the body where would you put it would you kind of put it with incense heated gloves? Would you put it in the core and the the overall consensus from that study was that it would be best to be in the core because if your core is warm first that’s a good thing. And then second of all, it is going to allow more blood to flow to the extremities. So from that perspective, if you had kind of heating where would you put it? I think the best place is to keep your core warm and that’s really what your body is trying to do in general anyways, but again if if the question was if I could either pick a warmer than normal glove you know shoe cover or you know kind of a boss over my head I would probably pick gloves because I know personally I’m really really sensitive with hands and Nicole

Trevor Connor  1:54:32

will lie. I love my heated socks. I knew you were gonna say that. I absolutely love my eyewear. I’m inside

Chris Case  1:54:41

and you’re getting pretty wimpy. Yeah, wearing heated socks inside. Yeah,

Trevor Connor  1:54:45

I’m getting old.

Chris Case  1:54:48

This is after you’ve put on your Mr. Rogers sweater or your cardigan and taken off your loafers?


Yeah, pretty much. Okay.

Chris Case  1:54:58

All right. Dr. Chung, I don’t know if you Remember or not from the previous time on the show, but we like to close out with our take home messages, you get one minute to encapsulate your life’s work, or at least, or at least all of the things we talked about in this episode. So yeah, what what would you say is the most important message for people to take away from this episode?


I would say the most important message is, you know, don’t fear the extremes. I know, we’ve been talking about a lot of crazy studies that I do. But you know, I kind of do them so that you don’t have to. But the big thing is, you know, you can exercise in extreme heat, you can exercise and extreme cold, as long as you take kind of precautions, and some more long term precautions, such as if you’re going to be training in or racing in the heat to become gradually over time to be adapted to heat to have appropriate cooling strategies, hydration strategies, all of these things, and then really listen to your body, being really in tune with it, and go with your brain because your brain is there ultimately, to protect you. And I think that is the biggest takeaway message for the heat for the cold is, you know, you don’t want to risk damage to your body, so you want to stay warm. So again, overdress route, then under dress is the general rule, and that you can’t really adapt to it. So the only thing you can do is behavior, which means warming up gradually and using clothing. So I would say those are the big kind of takeaway messages to have. And, again, you know, otherwise, you can go and exercise you can compete in the heat and cold. We’ve seen that in, you know, the Tour Down Under, we’ve seen that in extreme events like marathon de sub. And we’ve also seen that in polar explorers, it can be done with a combination of right clothing, right attitude and right kind of physiological preparation. Trevor,

Trevor Connor  1:57:04

what do you got? I am contractually obligated just one minutes, which is in cold weather. overdress don’t underdress. To give you one of the guidelines that everybody’s shocked by below 70 degrees Fahrenheit 21 degrees Celsius knee warmers below about 5560 degrees Fahrenheit around 1415 degrees Celsius, legwarmers, I am likewise contractually obligated that if I’m ever on a ride with one of our listeners, and you are underdressed, I will bow my head and nod back and forth slowly and complete discipline.

Chris Case  1:57:48

And the head motion would not be up and down. It would be from side to side. Yes.

Trevor Connor  1:57:53


Chris Case  1:57:56

Well, I have no contractual obligations. But I will talk about the sort of the psychological component here as I love to do. Yeah, I think I mentioned it already. There’s a The human body is is capable of doing a lot of things to keep within that range that it loves to operate. And we’ve discussed it, it’s the mechanisms by which it does that. There’s the clothing component that is critical there. But I think on top of all of that, one’s mindset is almost as critical here. And you can get used to things gradually, you can throw yourself into the deep end in certain situations, with some amount of caution, to see how you react to it and realize, Oh, that’s really not that bad. Or, oh, I can deal with this or get used to it. So despite all the things or because of all the things that we’ve said. And in regards to the psychological component, yeah, it’s like Dr. Chung said, you can do these things with the right preparation and the right mindset and the right equipment. So get out there. And we live in a we live in a place driver now. You lived in a place before that allowed you to test the capabilities of cold weather writing. Now you live in a place where extreme temperature changes and weather changes are a daily occurrence. So we get to practice all of this all the time.

Trevor Connor  1:59:27

I five cold is rods. We’re all in Colorado, Colorado. Yeah. Can get nasty here


quick. Yep.

Chris Case  1:59:34

Well, thank you again, Dr. Chung. That was an excellent discussion. Always a pleasure having you on the show.


Oh, thanks for having me back and hope we can get together for a ride sometime soon.

Chris Case  1:59:44

Yeah, absolutely. Hopefully not in your chamber or anything like one of the conditions you try to memorize.


you anticipate or what I was actually


Yes, I did.

Chris Case  1:59:56

a mad scientist. I knew what you were thinking.

Chris Case  2:00:04

That was another episode of fast doc. As always, we love your feedback. Email us at Fast Talk at Fast Talk Labs.com or if you prefer, record a question on your phone and send us the file. Subscribe to Fast Talk wherever you prefer to find your favorite podcasts. Be sure to leave us a rating and a review. The thoughts and opinions expressed on pastime are those of the individual for Dr. Steven Schoen, Nick league and Whitney Garcia and Trevor Connor. I’m Chris case. Thanks for listening.