The Cold Truth: Protecting Performance and Function in Extreme Conditions

Dr. François Haman | University of Ottawa

Dr. Kevin Rindal | Vimocity

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Resources

Winter Readiness Training Guide

Cold isn't just uncomfortable. It's the second deadliest environmental stressor.

After a lack of oxygen, we're really, really well adapted to heat, but not to cold. And the way we got used to cold was to making the right decisions. Never blame your biology. We all suck in the cold.

Dr. Francois Hammond has spent 25 years studying cold exposure from Arctic communities to special forces. Every field athlete that works in lower temperatures needs to know the hidden ways that cold effects our minds, our bodies, and our longevity.

Temperature is at the basis of every single chemical reaction in your body. This is why our body's really obsessed at controlling it. Planning is central. You don't plan it, you will get hurt.

This is the WorkReady podcast.

Cold is one of the most common job site exposures. And one of the least understood, Dr. Francois Hammond is a researcher and a professor in human kinetics whose work focuses on how humans respond to cold. Dr. Hammond, thank you so much for joining us on the Work Ready podcast. I'm really excited about this conversation.

Yeah, I'm super happy to be here and I think there's a lot to discuss right now, and the timing is, uh, is pretty, uh, pretty good when you look at everything that's happening right now, uh, across the US and across Canada. Yeah, we're recording this on January 27th and pretty much across all of North America, I think we're in single digits and tons of snow and ice, so yeah. Could not be more timely to have this conversation.

So humans are tremendously vulnerable to cold, uh, even more than heat. We're really well adapted to heat, but we're not well adapted to cold. And it was actually very interesting in looking at, uh, how the body responded to cold. And I was really flabbergasted to see where this took me because right now the interest towards cold is tremendous. All the changes in climate that we're seeing where people thought was gonna get warmer is actually we're getting these fluctuations that are insane in temperature, even going to the lower temperatures. And I kind of realized the importance of the work that I did, and I've been doing it for the last 25 years, studying cold.

I did a lot of fundamental work, uh, looking at basic energy metabolism, nutrition, but I also work with, uh, soldiers. So I come from military background. Both parents were military, so I kind of grew up on bases. And for me, I always did military research on the heat side, so looking at protective equipment for, uh, soldiers and looking at the heat strain. And that was mainly during, uh, all the wars that happened in the Middle East and, uh. But I was always doing kind of my cowork in parallel because I was also working with First Nations in Northern Canada. And in 2017, uh, I was approached, uh, to do some work with NATO. And uh, basically ended up doing a research in Finland, uh, with soldiers. And, uh, when I came back, started working with special forces across the US, uh, worked in Alaska, uh, worked in uh, Canada, worked in the Netherlands, Switzerland, um, even Argentina, which, uh, gets pretty cold, uh, in the winter and was doing a lot of training for the military.

And I did learn a lot Being in the field, it creates a lot of humility for most researchers that come in thinking they, they know their stuff and then they show up and they realize how much they still have to learn. So I did learn a lot from being around these guys and learning the approaches that they used. Well, I appreciate that you haven't spent your whole career in a lab and you actually get out there and understand what these conditions are like and Yeah, I would've lost my mind just being in the lab all day or in front of a computer all day and I kind of need to go play out there. And I think it's good for the mind. Yeah, kind of bruise stuff, but it also allows you to make that connection.

Absolutely. And like you said, we focus so much on heat stress because I would say proportionally we have, like, we have customers in Arizona and they had like a hundred straight days, over a hundred degrees Fahrenheit. And so, you know, heat is a real thing and there aren't quite as many, uh, days over the course of a year where you're below freezing. But I think one of the things that has really stood out to me, as in our conversations is that it doesn't have to be freezing for people to experience a cold, uh, related injury. And so maybe you just walk us through the fundamentals of thermo regulation because really it, it all comes down to thermal regulation and the temperature, you know, doesn't have to be freezing for us to, to start to be challenged from a thermo regulatory standpoint.

And you have to remember that cold has been used in many occasions, even at war, to basically destroy full armies. Napoleon went through it, uh, Hitler went through it. Trying to face these very dramatic cold conditions is tremendously difficult. Um, and it it is more subtle to a certain extent. If you look at the first World War, when we first, uh, when Trench Wood was really well documented and people realized it was an extreme cold, it was constant exposure to temper temperatures below 15 degrees Celsius, static wet. And this created a lot of neuropathies that nobody really was, was talking about. And it's almost like all that knowledge that happened more than a hundred years ago, we've kind of put aside, like it doesn't exist anymore and people are kind of exposing themselves on a regular basis to these conditions.

So when it comes to cold, it's still the basic. Physics of heat transfer. So we basically lose heat through conduction, convec. Uh, I'm gonna start with conduction radiation. Yeah. And explain these as you go through 'em. So conduction first? Yeah. Well, conduction is basically contact with any cold surface. So conduction needs contact. So it could be a tool, so you're holding onto a wrench or a pair of pliers or whatever that direct contact, it's gonna be based on the gradient of temperatures. So the, the temperature is lower of the object that you're picking up. It will start cooling down your hand. So your hand starts pretty much at 33 degrees Celsius. And anything that would be lower temperature than this will start cooling your hand. So, and, and feed are the obvious one because as you're not moving, you can actually, I was pretty impressed. I was looking at some of the data from the, the Arctic, from Canadian data and I was looking at boot temperatures. The outside boot temperature was, you know, at the temperature of the environment, but the inside of the boot was actually close to freezing. Which is surprising, you would think that boot would be able to protect you somehow, but it is protecting you to a certain extent. But it's being, you're losing so much heat through conduction that your boot is actually cooling down. So, so this is conduction.

The other one would be radiation, which is any warm object that will be radiating heat towards you. So a fire is the best example of it. If a fire is gonna radiate, you don't have to touch it. Not a good idea. Don't put your hand in the fire, but the, just through radiation, you will pick up that heat. The sun is our most ultimate example. Okay? No sun out. You feel, especially in the, in cold conditions, you feel the difference immediately. You're gaining heat through radiating heat, radiation. And we know about radiators, we know about all these things that are used, uh, for, for heating houses and heating spaces that we wanna warm up. So that's the, that's the other one.

The other one is, uh, evaporation. So evaporation is sweat loss essentially. So I can actually be dripping with, with sweat if it's not evaporating. I'm not losing heat. So, and this is based on the difference in humidity with the environment. So one place that we lose a lot of heat, and we can talk about it in terms of cold exposure, is through the mouth. So we tend to focus a lot on skin and go, okay, well yeah, my skin's not exposed. I'm not losing heat by evaporation, I am losing, I'm always losing a bit of heat through evaporation and this is why my clothes will become wet inside. It's all that evaporation. But the one we always forget about is actually breathing. Breathing has tremendous impact. It's about 20% of the heat that you lose in, in a, in a cold environment. So it's, there's a lot of heat being lost. So you, you basically cool down with the cold air comes in and when you exhale you, you're getting rid of extra heat that can actually cool your body if you're hyperventilating. So it's very important to protect nose and, um, your, your nose and your mouth. And it's kind of funny 'cause if you look at muskox, so always look at the environment for these experts of dealing with, uh, air exchange. And the muskox actually asked. Little, uh, spirals or vortexes in their nose to be able to rewarm the air before it co uh, it comes in and it kind of tells you how much, how important it is not to, uh, to to be able to protect your nose. So evaporation is a big deal.

And the other one that plays, uh, so now I got conduction that's affected by the difference in temperature. Radiation is a difference in temperature and evaporation is also based on the difference in humidity. But the one that really has a lot of impact and um, we're gonna describe this in more detail, is convection. Convection is basically maintaining these gradients. So even though I can create my little bubble and think I'm gonna be well protected, 'cause I got my little bubble, I would tell you in the cold, I'm literally more worried about the wind than I'm worried about the temperature. I can protect against temperature extremely well. I got all the equipment I can protect against it fairly well. With conduction, I got good minus 100 boots I, uh, Celsius and I, I, I can really protect myself from, uh, from now on. All temperatures will be in Celsius. It's probably gonna be easier if people wonder I'm gonna be working Celsius, but anyway, but that convection maintains that gradient, which means that, uh, when you're exposed to the wind, even though you think you can actually warm up, you're actually cooling down tremendously fast. And the windshield factor is the good example of it. Like a windshield factor tells you about the effect, uh, of, of the wind. The other part that the windshield factor tells you about, again, linked to convection, is the time at which, uh, how much time is gonna take you before skin starts freezing. You can try to ignore this and make believe that your skin is tougher than somebody else's skin, uh, you will get in trouble 'cause your skin will freeze like anybody else's skin. Uh, eventually if you're exposed to that, to that wind. So one of the things I always say when it comes to wind is you wanna be, be able to protect from it as much as you can to avoid, again, that bras byte and to, to, to, to avoid causing these additional problems.

So these are the four main principles of heat transfer. And all the equipment that we have is gonna be based on protecting against, uh, this heat transfer. Um, and it's all based on basic physical principles. And so when we're thinking about the term thermo regulation, it's almost like a thermostat in our house. It's, it's our body saying we want to keep our core temperature at a certain temperature, and if it starts to get too hot or too cold, our body's gonna make adjustments to try to, to maintain that, that internal temperature. Is that a good summary of what thermo regulation is?

 

Yeah, so, so that's a great summary. So we got something called a thermal neutral zone, which is basically a zone at which our processes are, are good enough to maintain our core temperature constant. And we don't need to add any extra effort if you want to be able to maintain that temperature. So in humans, we're around 26 degrees Celsius. Uh, it does vary based on your body mass, by the way. So when we're gonna talk about body mass, again, body mass is a big deal. Like in when you deal with cold or, and even the heat, your li your body mass is basically your sink. It's the amount of storage you have, like it does play a tremendous role. So, so we have that thermal neutral zone as we start cooling down, and this is where clothing helps, right? So if I have clothing, I can actually extend, 'cause what I'm bringing is I'm bringing my. Tropical environment, which humans are very good at. I'm bringing my tropical environment with me into cold temperatures. So what you hope is you're never gonna be affected by cold, but the reality of is that's not the case. You will get to a point.

So if you're not dressed and you're in exposed to cold temperatures, eventually what's gonna start happening is I start cooling. My hands are gonna get cold. My feet are gonna get cold, I'm gonna start shivering. Uh, I don't shiver because I hyperthermic necessarily. My core temperature is not necessarily decreasing. It's the first warning sign that my skin temperature is decreasing. Then eventually I'll become hyperthermic and my core temperature will start dropping. On the heat side, one thing that we see, uh, which is a very good sign, is increase in heart rate. My heart rate's gonna accelerate. I'm gonna start breathing faster 'cause I'm trying to lose that heat. You remember the effect of evaporation, like breathing is a big deal. So as I'm hyperventilating, I'm losing more heat. And your body knows, and dogs are the experts at it. Like you, you see dogs, uh, getting rid of that heat. The tongue is almost just hanging out and they're just breathing super fast. Goat's also very good. They, they actually keep their brain school through breathing. And then you're gonna get these responses and eventually, if I can't protect enough, my core temperature is gonna start increasing. Right? So this is how your body responds to try to regulate temperature. Why do we regulate temperature is because it's at the basis of every single chemical reaction in your body. Your chemical reactions are affected by temperature, affected by the change in pH and affected by, uh, uh, by the amount of substrate or the, the, the amount of, uh, of fuel that you have, let's say. But temperature is a big deal and pH is a humongous deal. So this is why our body's really obsessed at, at controlling it.

So I'm a construction worker, I'm driving to a job site. I've got the heat on, it's, you know, zero degrees Celsius outside, and I don't notice anything 'cause I'm in the cab of my truck. I've, I've got the layers on. I, as soon as I open that door to go outside, now I'm encountering what you just talked about it, the conduction, the convection, the evaporation, all these different things that are trying to cool me down when I encounter that environment. So, uh, so I have to pay attention to, you know, am I sweating when I'm out there working? Are my boots sweat or are my gloves wet? Do I have a barrier between my hand and. Metal tool that could cause that loss of heat. So maybe describe some of the challenges that, that people have to go through and how they can start to make some of those decisions on how to win that battle when it comes to, to cold exposure. 'cause there there are about 20 different things that people need to be thinking of.

Yeah, and it's kind of funny 'cause I, I, I'll start, I mean, when you become a cold researcher, you become a cold researcher when you're a kid, right? If you grew up in these cold conditions and, uh, I've had tons of frogs by, I've had all kinds of stuff, and this is how you learn, okay, this is gonna freeze my skin when I do this. I, I need to make the right decisions. So I literally have 56 years of experience dealing with cold temperatures. When you think about it, and again, I grew up in an environment where we were exposing ourselves. We were skiing, spending a lot of time outside, a lot of time in nature. And we did get super cold. We did shiver, uh, the environments, this type of growing up has changed over the years. 'cause I think the, the kids now are not as exposed as we used to be. Uh, the cars are much better. The environment, the equipment is amazing compared to what we had. We had the old Ski-Doo boots and if there's anybody listening close to my age, you know what we I'm talking about. But it was kind of these blue Ski-Doo boots that we would have. And they were fine for a while. They would get wet and then your, your feet were just ready for frostbite and it would get, it would get actually pretty nasty.

 

So you kinda learn that behavior and humans are not adapted biologically to cold. We're adapted behaviorally to cold. We're actually adapted to heat. We deal with heat tremendously well because we can sweat. We're one of the mammals that sweats. We're the mammal that sweats the more on the planet. Like we have rine glands, we can, we can sweat so much that we can lose a lot of heat. So we're really, really well adapted to heat, but not to cold. And the way we got used to cold was to making the right decisions. So anytime you show up in the cold, never blame your biology. We all suck in the cold. We all suck. So you gotta start with the premise that your behavior, your decision making is key. When I get anywhere, let's say I'm gonna go skiing or I'm ready to go, even when we were doing some trapping up north, or we're leaving the house and we're getting on the, uh, the sled to go trapping. I would prepare myself in advance. What I would do is make sure to have dry socks, to stay dry, even expose myself a little bit to the cold, not go to these, this extreme heat because you're wearing all these layers and if they get wet, you're gonna take 'em outside and everything's gonna get worse.

When I'm in my truck, uh, it's the same thing. I rarely put heat on independently of the temperature outside. I rarely blast the heat, especially not at the feet. I'm gonna put my gloves on the, uh, on the vents, on top, the, uh, the windshield to be able to, to dry them. So I make sure they're always dry, always heated up, and as soon as I come out, I change my socks immediately. I change the dry socks. So these are habits that, again, I can generalize them. This is the Haman, uh, 1 0 1 training for myself. Does it apply to everybody on the planet? No, it applies to me. I kinda learned these tactics as I went through. Did learn a bit, a bit from my dad. Uh, again, but again, my dad made some decisions. Never shoveled without, with gloves, never. Yeah, always bare hands so he wouldn't get his hands wet. Uh, so you learn that extreme right, which is probably not the best decision when you think about the risk of damage. But again, in his, he never had a hat that was fully covering his head 'cause he wanted to be able to make sure he didn't get too wet. So, but making all these decisions again, have to be planned. It's, it's something in the cold time matters and you need to plan these things and, and I think for me, this is what I've learned about dealing with cold is very different than learning how to deal with heat. When I go down south, I throw a few things in my bag and I know the worst thing I'm gonna get as naked as I can, uh, that people can tolerate and basically expose myself to shade, have water, and I'll do fairly well in the cold. Planning is central. You don't plan it, you will get hurt.

In cold environments, why is, uh, dampness in like our clothes being wet? One of our biggest, uh, threats, well, it basically increases conduction. So, uh, what it does is gonna increase conduction again when we come back to trench foot. And the risk of developing, so we call them non freezing cold injuries to make it look smarter, but, uh, trench foot, it actually works or trench hands, but they're basically damage to the nerves, right? So we're, we're creating damage to the nerve. So wet and cold is the perfect recipe to create these things, but one thing that cold does it, it takes away from the insulated properties of the clothing. So if I take wool, wool is kind of a huge, an amazing thing 'cause it's a natural fiber, uh, people have learned to use it over. Millenniums to deal with, to to be as c deal with cold. And what's amazing with um, wool is that even if it's sweat, it still retains, uh, its properties in terms of an insulator, it's not very comfortable. Um, but a lot of these cotton socks that we have, a lot of the, the, the equipment that we have once it's wet, and, and it would be the same with wool eventually. Like if, if it's drenched, eventually it will take out the insulative property of the, to be able to help you deal with the conduction, uh, effects that you would have at, at your feet or even at your hands.

So this is why you need to stay dry, like wet clothes. So we always say work wet, uh, rest dry. So even if I'm wet and I'm exercising, I'm still producing a lot of heat, I'm gonna do fairly well. But as soon as I stop and this is something I do systematically, I stop, I get dry. So I always have two sets of everything. I got my dry stuff and my wet stuff. And uh, now there's pretty amazing clothing that allows wicking so we can actually get the sweat away from her body. But we still have to think about that, that outside layer, right? If it's not allowing for that sweat to leave, well then it's gonna start accumulating. So for me, cold is managing wetness more than it is managing temperature.

So everyone listening, if they're working in cold environments, they should definitely have a dry bag with them, with extra socks, extra gloves, probably an extra undershirt so that they can layer up in case they do get sweaty or wet. Is that, yeah. Do you recommend that? It pretty much, uh, instantaneous as soon as you change to dry. It's amazing what it does. Like there's also a comfort level. 'cause as soon as you start getting cold, so. With the heat where we're kind of funny, it gets warm, we're gonna put water on ourselves or whatever. If we're able to do it again, and if we're very sensitive about what's going on, we can protect against heat shock fairly well. If we get access to water and shade, we'll do pretty well with cold. There's kind of that little panic that that is created and we go, okay, I'm just gonna suck it up and I'm just gonna keep going. We kind create this in our head, right? And it is tremendously dangerous. What the best thing would be to just change to dry stuff. As soon as you get that feeling about, okay, my hands are cold now. Okay, I'm gonna switch my dry gloves. Gloves, my feet are cold, like I'm gonna change my socks, right? Just to create that comfort and that whole concept, uh, we're just gonna suck it up. Uh, it doesn't really work with cold 'cause you can try it and it will catch up to you eventually. If it doesn't catch up that day, it's gonna catch up. A month later is gonna catch up. I mean, the damage that I've seen in soldiers of ignoring some of these signs is actually changing their careers and the career path, and it can actually end a career because the damage is so profound.

 

So yeah. So managing, being able to have that dry clothing, to me is central. Yeah. Let's expand on the trench foot concept and the non freezing cold injuries and the long-term damage that can happen to people, because again, in, in a lot of people's minds are like, ah, it's not freezing. I didn't, it's not icy out. Like, I, my feet are just wet. What's that gonna do? But over time, what, what is the cumulative effect of that type of exposure?

Yeah, and it is subtle. Like it's not something, it, it comes from years, uh, I'm gonna say years, but I mean, it's less than this. I mean, it could happen depending on your level of exposure. Like it could be a month or it could be even less. But the whole idea is. Basically I, I'm, I'm damaging the skin and the nerves just from that wetness and that cold in a way that is not gonna go away. And it's funny, when you think about frost bite, like you get a frost bite, you're gonna rewarm it. It's probably not gonna be fun for a while, but as long as you don't lose your toes or your fingers and it's about, you know, maybe 10% of the injuries you see in the cold. 'cause people are fairly good at protecting against frostbite. But the ones they don't see is that, again, that little underground. My hands are super numb. Uh, they're aching, but I'm just gonna ignore it. 'cause you know, I probably don't have frostbite and I'm just not, I'm just gonna keep going. Right. So I think for me, um, it becomes a little bit like something that you're almost living on the edge when it comes to trench foot. You have a job to do. You have something to do, and this is kind of always on the background. And you go, it can be that bad or it's not gonna be that bad. But it's that. And again, even in the work that you do, like, you look at physical injuries, like any type of sports injuries, repetitive movement, you're, you're repeating movements constantly. It's a little bit what's going on. Like you're, you're basically straining your body dealing with cold, and you're creating that damage that's gonna be down to the nerves. And it's very, very subtle. Like it's a, it's kind of a, a silent. Uh, a silent way to damage your body, which where the frostbite, it's actually gonna hurt. Like, you're gonna feel that pain, like it would be like a tear or something's breaking, like you feel it. You don't get that with non freezing cold injuries. And I think this is where that injury is, that it's well documented by, in the scientific literature, I've published a few papers on non freezing cold injuries. And in the military it's super well known, super well known, and most people, especially in North America, will tend to ignore it or just not talk about it. And your hands and feet now become super sensitive. Every single time you're going to the cold in a way that you're gonna look at it and go, I shouldn't be feeling this way. It hurts, my feet hurt, my hands hurt, and I can't do, I can't be in the cold right now. That's how bad it gets. With frostbite, it's almost, it's, it's depending on the level of frostbite, but if you look at, you know, superficial frostbite, it's not gonna create that level of damage. It's not gonna be that profound. With, with trench foot, non freezing cold injuries. The damage is so profound, it will stay with you the rest of your life.

And I'm sure a lot of people listening, including myself, have a little bit of that mirror my fingers and toes when I ski it. Oh man. They just ache so bad at, at certain times. Uh, and it doesn't take much. No. What are, what are some of the lessons that you've learned from the indigenous, uh, folks, uh, that you've worked with about how to manage workload so that you don't sweat? Because it seems like you almost have to have the strategy of how far do you push it so that you don't start to get sweat, um, sweaty and wet, and then that puts you at higher risk?

Yeah, and I, and I can say this and I know some of my friends up north, will, will, will be watching this in the communities, but I mean, they find that we work fast. I mean, we show up and you know, we gotta be, we're coming from the south and we're ending up, up north. And everything we want to do, we want to do it fast. There's a job to do. You wanna go trapping? Okay, let's, let's just hammer away, you know, and you're gonna start digging a hole in the ice and you're going full blast and, and all that type of stuff. And they look at you and they go slow down. Okay? So there's a few reasons for this, and it's not just about the sweating, but there's that concept of you sweat, you die. So, you know, when you're far from a community, you're gonna be on a sled driving back, you're talking eight hours. Like I'm sure some of the guys can relate to this big time. You gotta pace yourself, which means that if I'm going too hard, I will get my clothing wet, I will get wet, I will get drenched. Right? A lot of this, this warm. Clothing is actually not made to operate at very high rates of sweating. I know a lot of people have Gore-Tex, like obsessed with Gore-Tex. I dunno, what's your feeling about Gore-Tex? But for me, with my body size and my capacity to sweat, I always got wet under Gore-Tex. So I would sometimes rather be wet by rain and not have to deal with my wet clothes. So I would, you know, kind of take as much clothes off, keep, keep the stuff dry, and even if I get a bit wet, I'd rather be wet than, than having that coat on and feeling like I'm my, I'm just heating up. So I'd rather have the opposite.

So a lot of this clothing is actually made to protect you against the difference in temperature, which makes it very susceptible at protecting sweat. So sweat's gonna start accumulating into this. So your work rate is a big deal. And one thing I've learned from the north is the guy's pace. They work slow. They always felt, again, there's a few reasons for it and I think we're gonna talk about them. The risk of injury, the risk of making a bad decision. You got the extra strain of dealing with cold, walking in snow, sleepy slippery surfaces. All of this is attenuated by slowing down your work rate, right? In addition to sweating less, which is again, protecting you even more so you're keeping and your clothing. So I would say one thing I've learned is that work rate matters, especially in the cold. So we know what we, we know in the heat, it's the same thing. We talk about work rate in the heat, we kind of have the impression that in the cold we gotta do the opposite. You're cold. And that's how I was raised, right? Yeah. Your, your cold just started moving more and the more you moved, the more you were sweating and the, the colder you got. Right. So it's kind of finding that right balance between, okay, this is my work rate, I'm monitoring how my body's responding, and this is tremendously important to be able to monitor and do a body scan. Okay, what's happening at my, at my body? But I think to me, work rate and sweat rate, that's what you need to, what I've learned from the north is exactly this. And what I've learned is to calm down when I show up in the cold conditions, just like I would do in the heat. Slow down. Slow is smooth. Smooth is fast, right? Yeah. Like special forces say. That's right.

Uh, you had mentioned convection, so the wind plays a huge role in terms of how our body's able to thermoregulate as well. What are some of the things that people should watch for of win-win can really start to impact, uh, body temperature. So there's a few things with wind, I would say, and snow, which is again, would be different with the heat. Uh, is it snowing outside? And when you got snow coming into your face full blast, uh, it matters, right? You're gonna get into a whiteout and, you know, Mount Washington's wild renowned for this. You get these huge whiteouts, you can't see anything. So watching for wind is a, a tremendous factor. The other thing with wind is also making sure what parts of my body are exposed to that wind. 'cause wind ultimately will increase the risk of frostbite big time. So it, I mean, we can talk about it the whole body level. Like of course I'm gonna be cooling down faster, but even just having my cheeks or my nose exposed, just a bit of skin. I mean, I've done an experiment at, at Simon Fraser University and my colleague, which I used to call a friend, put me in at minus 60 degrees Celsius. Okay. And minus 60, you got no room to maneuver. Any type of little skin that is showing will be freezing almost immediately. And this is how you learn how vulnerable skin would be to, to frostbite while the wind's just gonna aggravate all of this.

So you gotta look at this windchill factor and see, okay, how much time before I get this frostbite to be able to make these decisions, but also making sure that I'm, that I'm well covered. And, you know, depending if I'm working at heights, uh, if I'm working on the ground, I never like being high when it's windy, uh, even though I used to fly planes. Uh, but in the wind you're vulnerable big time. Like when, when, when you're dealing, you're, you're working anywhere high. You're extremely vulnerable to that wind because you won't be able to protect quickly. If you need to protect from it, you're fully exposed. So your level of exposure is a big deal, like if, if the wind is high. But you can protect yourself. So one thing I've done ice fishing is I put my truck in a play in a place that was protecting me from the wind. I would put a tarp up to be able to protect myself. But if you can't do that again, the ice is too thin and now suddenly I'm fully exposed. 'cause I can't take my truck there. I might put a tent if I'm lucky, but you gotta find ways of protecting yourself against that wind. And, and you do need to look at these windshield factory tables like they're well made, uh, they're extremely useful and you do need to understand them.

So if I'm a foreman leading a crew or working in a cold environment, uh, and I'm doing a pre-job brief, I should be talking about, okay, wind exposure, uh, windchill factor outside temperatures, any type of precipitation, maintaining, you know, a work rate that's not so heavy that they're gonna be sweating and increasing their, their risk for experiencing a non freezing cold injury. What are some of the other things that people should think of when they're, they're communicating with the crew and planning the work?

 

So, so it's interesting because again, what really popped into my head when you were asking that question is, and I just mentioned I was, I'm a pilot, wind conditions, temperature, even, uh, sun or cloud cover changes. You know, and in the plane you get basically, you know, information on a regular basis to be able to monitor these things to me. And it's de depending on when you're working, it's actually better if it's, you know, it's gonna be minus 20 and stay at minus 20 the whole time. 'cause you know what to expect. But it's never like this. And you look at the transition seasons like fall and spring and you get these changes, you know, might be worn during the day, but it's gonna be freezing at night, right? It's gonna be windy and you get these change in convection that are tremendous. So I think it's also being able to inform in advance of what's going on, trying to get a good weather assessment, uh, on a regular basis. And we have the technology now to do it, to be able to understand this, but one of the amazing technology we have is actually called humans. So if you got humans out there, is to be able to report on what the conditions are. On a regular basis. So, you know, from people on the ground. 'cause you can always look at these weather stations. They're gonna be well located, but they're not gonna be in your perfect location. They're not gonna be where you are. Um, and depending on the environment that you're in, you need to know, okay, this is what's going on. So regular, regularly checking on these conditions, how's the wind? Are you guys getting cold? All that type of stuff to be able to ask these questions. Like we, we need that quantitative number to make a decision. We don't, I mean we, we got sensors all over our bodies that are gonna be telling us all this information. We got, we got an amazing weather system, uh, detection system 'cause we're so vulnerable to cold and, and her body's gonna tell us what's going on. And I think one of the things is to monitor these things. And of course through this you gotta make sure that you get the right information. You know, when, when, uh, playing sports, um. And you even see it in the military, you know, sometimes you're not gonna give the full truth about what's going on, right? You don't wanna talk about your injuries. You, you don't want to talk about anything that might make you look vulnerable. But the thing to remember is you're keeping yourself, uh, safe, but you're also keeping other people safe. So if you don't wanna do it for yourself, do it for other people, because at the end of the day, it will make a difference to be able to, to get that information and to be able to, to provide to the form and exactly what's going on.

You brought up such a great point there. Weather conditions changing is probably one of the greatest risks. And so oftentimes you have the pre-job brief at the start of the day, but you probably need to have multiple check-ins if the environment is constantly changing. And last week, uh, we had a conversation and you shared this awesome chart and maybe we could spend the next few minutes talking about the different zones. 'cause I think that's a really important framework for people to use to understand the status of each person on their crew. 'cause everyone's gonna be different in terms of how they, you know, are handling the cold based on, you know, multiple factors. But what are some guidelines that people can put in place to understand where they fit from a risk perspective so that they can take early action so that it doesn't turn into something worse.

Yeah. And, um, I might kind of, uh, give a bit of experience coming from the Norwegian military. Again, there are people that are tremendous in arctic conditions and dealing with cold. And I gave a presentation, uh, to Canadian Special Forces. And, uh, there's a sergeant major from the Norwegian Special Forces that presented with me. And he's a field guy, like he's a hundred percent in the field. Patrol commander, like knows how people handle cold. And one thing he said is every hour he would monitor all the people under his command and he was non-negotiable and he would even physically look at feet, touch feet to make sure that there was no damage. But he, the reason is if the person's damage or getting hurt, you will have to deal with it eventually. And in the cold, this is a big deal. Like this is not something that is trivial. So. Yes, the person can monitor and we'll talk about that chart. 'cause I think it's amazing for people to be able to monitor themselves, but also I think it's a way of getting the information to the people that are the decision makers and saying, okay, this is where I'm at right now. And it kinda gives an objective way of, of dealing with this, uh, going through the chart. But it comes down to the idea that, you know, it does come down to regular monitoring and it does come down to be able to understand, even though everybody responds differently, we all go through the same stages, right? So it's to be able to follow these stages and there's factors affecting, uh, affecting it. Did I sleep? Did I eat well? Am I well hydrated? 'cause it affects my blood flow. Am I well hydrated? Uh, am I overly stressed? All these things will affect that chart and when everything occurs. So again, yeah, we can look at the chart, but this is something to keep in mind. This is a way of informing people about what's going on in terms of cold conditions.

Yeah. And we're gonna pose this chart in, uh, that conversation that we had last week in the show notes, so people will have access to the additional resources, but walk us through the different, um, segments, the green, yellow, red, orange, red. I think that's a really helpful way to just visualize what that risk looks like.

Yeah. So what's interesting with that chart and um, back in 2017, I was on the NATO panel working on, um. Medicine and physiology. And I met a colleague there called Boris Kma, uh, professor. He's a, he's a researcher with the Netherlands military and, uh, very good modeler. Like he understands how to model the human body and how the, the, uh, how different body sizes, body shapes will actually respond to cold doing amazing stuff. And we started working together very closely. And the whole time we're looking at this going, there's too much variability between people. And that's the thing you need to remember with cold, there's so much variability that you cannot compare yourself to another person. You don't have the same history, you don't have the same biology. You don't have same body mass. Body mass is your biggest protector. Everybody's obsessed with percent body fat, but it's actually the overall mass that is, that really matters. So everybody's basically their own experiment to a certain extent when it comes to cold.

So we're trying to think about this and we go, okay, one way to do it is to go through, instead of you looking at it in terms of time, let's look at it in terms of events that occur. So we separated into the green zone, yellow zone, orange zone, and red zone. And when you look at the green zone, it's ba, it's a zone where you're not affected by cold. And believe it or not, you could be into, in arctic conditions and be toasty and doing great. My skin temperature's not dropping my hands. My hands are doing perfect. Uh, I'm fully under control and I'm whatever temperature's outside of me. Everything's in perfect balance. And we do reach that, like I've been to pretty extreme temperatures and we're able to reach this, you know, through movement, through making the right decisions, we're able to get to stay within that green zone.

The yellow zone is when my hands and feet start cooling down. My hands are cold. My feet are cold. We were raised at a very young age, and I know I went for you, Kevin, but I was raised that way. When your hands and feet were cold, you just had to suck it up, and it basically, you didn't tell anybody. You just kept, you know, I'm just gonna ignore it. And, and, and kept going. So the Yellow Zones actually telling you otherwise, and what it's telling you is when I get into that zone, this is my warning sign, number one. This is the, the first flag that comes up, which means that now I make a decision if I stay into that zone, I risk non freezing cold injuries. I even risk freezing injuries. I risk losing dexterity, I risk making mistakes, and maybe getting hurt. Right. So what decision, what, what decision could I make to get back into the green zone? I need to warm up, maybe change to dry gloves and dry, uh, socks if I can't do anything else, but I need to start making decisions. And these decision, uh, can be various, but the whole idea is to basically get dry and get warm. Which is the decisions I need to make?

And why do my hands and feet get cold first and start tingling? Why is that, that early warning sign? So, and that's a great question. You know, I, I was kind of telling you that as a physiologist sometime I, I skip some very important details. So the body's response to heat is to vasodilate. It's basically to increase blood flow to the periphery, to try to lose as much heat to the environment as possible to maintain body temperature. The response to cold is the opposite. So the response to cold is to create vasoconstriction, which means all my vessels are gonna reduce in size and all the blood's gonna come into the core to protect my core organs. So it's almost like in my body's saying, I don't care about losing toes and fingers, like, whatever, like I got more of those ears. We can see it well nose, we can see it. Well again, I don't care. I can lose that stuff. So I'm just gonna keep the blood where it matters that if I, if I lose something, I'm still gonna be able to survive. So very rapidly, your skin temperature. It's gonna start decreasing at your hands and feet. The theory is that if my core is warm enough, I should be able to pump warm blood back to my hands and feet. And there's something called hunter's response, which is cold induced vasodilation. So I could get regular warm blood going to my hands and to my feet to be able to keep them warm warmish. But it's still my first indication that something's going on and my system is under strain. So I would call it level one of cold strain.

 

That's a really helpful explanation, and so now take us into level two. If I just ignore that and just blow past it. Yes. Have that mindset of like, I, I can grit this out. Yeah, yeah, absolutely. What are the risks? I'm just gonna ignore it. I'm full, fully vaso constricted right now, and my, my body's saying, okay, your hands and feet are cold, but you decide to ignore it. Eventually your skin temperature will start decreasing. Your whole body's skin temperature will start decreasing and shivering will start. Shivering is next level. Shivering is a good thing, by the way. So shivering is basically telling me, okay, I'm producing heat to be able to counterbalance that. That, uh, heat that's being lost or dissipated to the environment, and I'm, I'm fighting it right now, and shivering is tremendously important. The problem with shivering is we're also using the same pathways or the same, uh, the, the same way that you would get with voluntary contraction. Shivering is an involuntary, so we don't really control it, even though we think we have a amazing mind and we can control it. Everything you can try eventually, you're gonna keep shivering. So, but the shivering is gonna be competing against your fine motor skills or any even gross motor skills. Like, uh, there's two parts to shivering. One of them is continuous. It's a bit like tremors you would get for Parkinson. And the other one is called the burst. Burst of shivering. So burst is, is gonna occur two to, uh, eight times a minute, and it's tremendously strong. It's a very high intensity cont uh, high, high intensity, uh, muscle contraction. And what it creates is, again, you're gonna lose full control of your body at that moment. So shivering is more obvious. It's important because it's telling you that you're protecting yourself against that cooling, but it's also one level up. It's another red flag that flies up. And if I wait to that extent, I need to cool to rewarm my entire body. This is not just about rewarming hands and feet. This is my entire body that needs to be rewarmed. So now I gotta get out of that situation and start rewarming.

So that's like the body's fire alarm going off, saying, okay, now your core temperature is at risk. It's, it's entering that danger zone. So we've gone from yellow is hands and uh, uh, fingers and toes are starting to get numb. And then orange is when I start to shiver. Yeah. And you know, with shivering there is multiple levels of shivering. You can shiver so hard that it's not gonna, it's gonna be consistent. It's not gonna stop. It would be like constant contractions. Like, you should see the videos when I'm doing this in the lab and I'm shivering for one hour and you're bouncing off the bed. Like that's, that's, and this is not even the high intensity by the way. Like I would, I would be talking about, you know, level two of intensity. So there's five levels to shivering. Level one is no shivering. Level two is the one I'm telling you about. Like your whole body's shivering and you're bouncing off. If I fall in ice water and I come out, 'cause I stayed too long in there and my core temperature is low, this is level five. I have no control over myself. No control. You're in trouble. And it's good 'cause you gotta keep shivering 'cause that's the way you're warming up. You gotta keep shivering. But just keep in mind that even ignoring level one is not a good decision because if I'm ignoring level one and I wait for level five of shivering, you know, the, the amount of mistakes I'm gonna be making, uh, the risk to my body and the risk to other people is tremendous. So this is not something you can just ignore. Like, and again, people, I'm not shivering too much, you know that, that too much thing. Yeah. I already did a shivering. Yeah. Okay. I'm gonna be fine. I'm just gonna tolerate a bit of it. Well, no, that's a bad decision because by the time you, you realize you're at level three and four, you got full loss of your body completely.

And is level three and four when your chin starts to chatter as well? Yes. The chin is gonna be quick. So basically masser are the, the, uh, the jaw muscle. It's gonna start, uh, shivering very rapidly. So everybody shivers a bit differently. I don't really shiver from the jaw muscle for some odd reason. I tend to shiver from mainly my, uh, my chest is gonna shiver more. Some people shiver more from the legs. Uh, don't compare. Uh, so this is something I've shown in my research. Every single person shivers a bit differently. Respect yourself and your responses. 'cause not everybody's gonna do it the same way. Some people, I don't get this for some odd reason, so I don't get the the shivering.

 

The other thing that's important for anybody listening in to conversations is there's gonna be tensing up of muscles, which means that the speech will be blurred. So we use similar things with high altitude. I dunno if you're familiar with this. There was a researcher that was doing radial communications on Everest to try to figure out any type of, uh, hape or haze, uh, which is basically high altitude sickness, but also the effects of lack of oxygen. And she was listening into the speech, which was a controlled speech compared to how the person spoke when they were in that hypoxic condition. So reduce oxygen, and there's actually a difference. Well, in cold we get the same thing. And I, I know you know exactly what I'm talking about. I mean, when you're absolutely, as you say, swimming in cold water, you're swimming in cold water and then suddenly you come out and you can barely make a sentence, right? Yeah, yeah. Your tongue just feels like it's, it's locked up. Like it can't, you can't articulate orgs. Yeah. And it's mainly the jaw muscles are being affected. Like that's what I'm telling you. It's competing with voluntary contractions, which means that I'm comparing, I'm, I'm competing against voluntary movement of, of my tongue, of my jaw. So you can even hear it and you can even ask somebody, are you okay? Are you feeling okay? 'cause your speech is blurred. So this is also one indication.

So this is when you get to level orange, which is to me, we should never get to that stage. We should never get to that stage. And I know people will say, ah, I'm, I'm gonna stick to level yellow. Okay, well you can stick to yellow, but you're still gonna get damage. So I don't think that's a good decision either. Like you're always trying to aim for, uh, the green zone. And then level red. Obviously this is like really bad situation, like this medical emergency. This is really, really bad decisions. Yeah. Yeah. If you get to level red, it means my body temperature is decreasing. So this is no joke. You get out of that environment rapidly 'cause you're not, you're basically on a downfall. This is not gonna go well. By the time, uh, you reach a certain body temperature, your shivering is gonna stop. If I'm cold and not shivering, I'm in humongous trouble. Right? I cannot rewarm and I'm just gonna keep cooling. This is your body shutting down. So if you find somebody cold, not shivering, this is tremendous level of cold exposure and you need to rewarm the person from the outside, like the person cannot rewarm and will die. Okay. So one thing to always remember, 'cause I wanna say it so I don't forget it. Nobody's dead until they're warm and dead. So if you find somebody cold, nobody is dead until they're warm and dead, you will warm up that person. You take them where they, they think when they can be warmed up. You call emergency services, but never assume that somebody, because they're tremendously cold and not responsive that they're dead. 'cause people have come back from that situation. So just something to keep in mind, that's tremendously important.

So for me, it could happen accidentally. So let's say I'm walking and I'm crossing a lake, which I hope most people are not doing on a regular basis, but let's say I'm crossing a lake. Ice is thin and I fall through. That's the only time where you can hit that red zone in my mind. It's accidental. You get into an accident, you're stuck. This is accidental stuff. This is not stuff that should happen on the job. This is not stuff that should happen on a regular basis and not decisions that are being made. To me, this is a big deal. Like if there's one place you should never put anybody into as that red zone. Okay. So again, making this very practical, uh, crew out there. They're working in these conditions, they're doing their pre-job brief. Uh, again, we will give everyone this chart, but they should be talking about, here's what Green Zone looks like. Here's what Yellow Zone looks like. As soon as we hit any of these signs in the yellow zone, you need to go back to your truck, warm up, uh, change out your gear so that you don't progress from there. Any, anything else that you would add?

 

Well, what I like with the zones, and, and this is a little bit why we build it with soldiers, is that it allows a very objective way of saying it, right? Some people don't wanna spend all my, my index finger is cold or this and that. No, no. Just work with the, the zones there. So I'm green, everything's good, I'm yellow, I'm orange. Right? So by just throwing these zones, if people understand what's within these zones, it basically becomes a. A code that people can understand and very rapidly, even in communications, be able to express these zones and where you're located. Anybody making decisions can actually have a plan that if somebody gets in the yellow zone, this is our plan. Anybody gets in the orange zone, this is our plan. Okay, you come back through this route, we're gonna pick you up there and we're wor rewarming you. So instead of waiting for making the plan, you know, building the plane as it flies, which is never a great idea, try to actually make these decisions in advance. Anybody in the yellow zone, this is where we meet up. Anybody in the orange zone, this is what we do. Anybody in the red zone, this is what we do. And it just makes it very efficient in terms of dealing with these types of, of concerns and accidents.

I think we can't emphasize enough that. You can't just brush off cold and say, I'm gonna just get grit through it. I mean, this is not a time to, to just ignore that because the next part of this conversation that I wanna focus on are what are the cognitive impacts of cold? What are the dexterity impacts of cold that then could lead to even greater risk or injury? So maybe, if you don't mind jumping into the cognitive risks to start out with, I think that would be a really good place to expand on.

 

Yeah. So, so what's interesting with the cognitive ones is that they become very gray to a certain extent, right? Cognition is, is a zone where, when do I realize I'm making the bad decisions or when do I realize that I'm not doing the right thing? So, to me, cognition, especially when it comes to monitoring, it is a team effort, right? It's a team effort. Like if, if you realize, if you see somebody. You say something like, if you realize some per a person's not really making the right decision, you kind of, you kind of say something. So this is under normal conditions to me. This is a big deal in the cold. You just multiply that effect, right? I end up with more stress. There's more things I need to worry about. I need to worry about slipping. I need to worry about walking through the snow, getting to where I want to get, uh, worry about, you know, even holding on to cold objects, knowing that I'm gonna be cooling down my hands. You got all these things that are in addition, which, uh, you know, your brain is already full of having to do the job. That if it wouldn't be cold, it would still be challenging. Now you're adding cold on top of it and cold is a multiplier. Like it's a huge multiplier because again, you need to worry about wind, you need to worry, worry about conditions changing. You need to worry about all this stuff. You need to worry about where other people are as you're going through this. So it's hard to look at specifically what is the effect of the cold temperature on your condition, because the other part that we have, and depending on who it is, and it's okay to express it, you can be scared of heat and overheating and heat damage, just like the same way you can be scared of cold. Cold is terrifying. Cold is not something that should be ignored. Animals don't, don't ignore it. And animals have tremendous self-awareness and they will not make certain decisions not to expose themselves to the cold. One thing I've learned, again, working up north, they will not go out if they think there's gonna be an issue, they will not go out again with crews working, this is your job, but just keep in mind. Most people that have a choice that understand cold will not put themselves at risk like this. So you are putting yourself at risk and you are pushing the limits when you get into these cold conditions and your body knows it. So even that effect alone, without even looking at the effects of as I'm cooling down, as my hands are cold, my feet are cold, my capacity to make decision is being affected, just compound everything around it and you realize how difficult it is to operate in cold conditions.

 

Do you, would you say that we know that like pain can impact somebody's decision making and it can cloud judgment. People make riskier decisions when they're in pain. I mean, the discomfort of being cold and the elements, you know, pounding your face, you got, you know, snow blowing in your face. I mean, is, are those also distractions that would cloud somebody's judgment in their ability to make a safe decision?

Yeah, big time. And I'm just gonna throw something that's not scientifically based, but I'm just gonna throw it at you guys. 'cause I know a lot of people will associate with this when you have cold feet, I, I can deal with cold hands fairly well. Like, I know I can put 'em in places that are warmish and I can warm them up, right? There's a few things I can do to deal with cold hands when my feet are cold and numb and I'm feeling them geter. Ander, that's pretty awful feeling. It's all you can think about. And all you think about is actually your feet and your whole body's concentrating on my numb feet. And the feet are almost like becoming hard. And you're looking at it going, okay, am I getting frostbite? And constantly you're getting all these signals and, uh, dealing with cold by the way, I'm gonna situate something that can help people identify where they are. We have, uh, a nauseous receptors, which is basically detecting cold temperatures. They work at about 15 degrees Celsius, which is about 60 Fahrenheit, so they're gonna work down to 15. But the ones that kick in afterwards, 'cause we got two sets, are nauseous receptors. And as you know, nauseous receptors are used throughout the body to tell you that it frigging hurts. Mm-hmm. So there's, they're, they're basically pain detectors. And these ones kick in in the cold, which is, you don't get that in the heat, but you do get in on the cold side. And when these ones kick in. It will be pain and you will feel that pain. And the colder it gets, the more you're gonna feel that pain. You can learn to ignore pain 'cause we've all done it. You know, you ignore pain, you make believe it doesn't exist. But the reason is your body's telling you this. And again, that self-awareness piece where we have a choice with the brain, the, the, the mind body connection. I can decide to ignore it and just cut it off at the neck level and just ignore my body. I can try to do that and as, as you say, maybe some people are able to do it, but most people, the only thing you're gonna be thinking about. Uh, as the, the, the pain at their feet. Feet are amazing for this. They're one of the best sensors we have. They will tell you a lot of stuff, and, uh, you, that's the only thing going into your head. So any decisions you need to make will pass through your feet, which is gonna be pretty, uh, it can be a pretty bad decision.

Yeah, that's a great point. And that concept, uh, the nociceptors, which are the pain sensitive, uh, receptors that we have, there's this whole, um, theory called reation, which basically means that the input that's coming in and going up to your brain, your brain is what interprets the pain. And then it sends out a response. So like, if you touch a hot stove or something like that, uh, the messages go up to your brain, your brain sends messages to your muscles, you pull your arm away to avoid that. But we also know that. When there's a chronic stimulus of pain, what it starts to do is it starts to impact the motor cortex in our muscle's, ability to react in a coordinated fashion. We lose, uh, you know, strength or we can't activate those muscles at the same degree. And so let's maybe talk about how it's very important point, because I know if you ever walked with numb feet Yeah. Painful feet. It doesn't work. Yeah, yeah. Or have you ever tried to do a complex, precise task, like, you know, put a screw in, uh, to something and you're working at an awkward angle and your hands are cold and you keep dropping it and it's, so maybe explain how cold can be a safety risk for people who are doing like high energy or high risk work.

Well it is, and I'll give you an example. 'cause I, again, I, I may, maybe I have trauma, like, uh, this seems very trauma informed, uh, as you're saying these things. I got all that cold risks that I faced over the years and one of them, uh, we're basically on a sled up north and we get an issue and we need to pull out the wrench. And it was, it was minus, probably minus 30 Celsius. Like it was freezing. Like it was unbelievable. And you got these big myths and that's all we had. It was, were the big myths. So what do you think happens to the myths when you pick up that wrench? It's been kind of exposed to minus 30 for the last eight hours and you see the sun coming down and you pull out that W ranch. So the MIT just flies off. You go, screw it, I'm just gonna use my mit. And it's literally like holding a piece of fire. Like it was ridiculous. And, but you need to use it. You have no choice and you're kind of going at it, and you're going, and your whole body's telling you what are, are you stupid? Like what are you doing? So the amount of energy it takes you just to ignore, and it's exactly what you're describing. The amount of energy that it takes to ignore this is humongous. And that's what people, when it comes to cognition are dealing with cold. So there's a few things that occur to you as your hands cool down. You lose sensitivity at your fingers, your dexterity goes down. So I can't feel it as, as much. Plus I got these pain receptors that are sending stuff to my brain and telling me, drop that thing. Like this is ridiculous. It took us an hour to fix it. We just kept dropping the wrench, like we cannot get anywhere with that frigging wrench. And we're, we're wrapping it, trying to, but then your hand is exposed and we can hold it with the mit 'cause we couldn't get enough precision with it. Like, oh my God, like this was again, the risk associated with this. And just think about changing a tire by a roadside. You know, at these types of temperatures, and you gotta hold on to the, the wrench as you're, uh, uh, as, as you're trying to get the tire off and every single step of the way your body's telling you, what are you doing here? Like, this is such a bad decision. So I mean, the risks are humongous, like the risks are humongous.

So this is something we've been trying to address, is making sure there's equipment that people will keep on. 'cause it does affect dexterity. I've been doing some work with the US military, uh, US Army. They've been looking at trying to get gloves that have high good dexterity, good grip, but can still protect you from cold and frostbite. This is not readily available, by the way. So this is a big issue. A lot of them are bunching up, not very comfortable, um, and a lot of people are complaining about them. So when we complain, we just take it off. So. I think there's a, there's a big layer there in terms of complexity of how do you learn to function by keeping your dexterity, reducing the risk of cold, and be able to not affect your decision making. Like there's a lot of things going on and I think it is part of training should incorporate some of these factors.

Absolutely. And even just thinking about PPE, you know, I think that this says a lot about why we should treat people like industrial athletes. 'cause industrial athletes, they use equipment that professional athletes are gonna use to be able to perform in those demanding conditions. I think that those are some of the cool opportunities and construction utility work of how do we take what we're doing with professional athletes, bring those same concepts because they are a performance, um, you know, people.

Let's talk about, um, the risks associated with musculoskeletal injuries. Uh, when it comes to cold exposure, I think that that's something that a lot of people don't understand that they are at higher risk, but when your blood is going away from your extremities, going to your core, that means that your, your muscles don't have the same level of blood supply. Tendons are not, um, quite as responsive. So there is definitely that risk, uh, for an injury. And you mentioned slips, trips, and falls increase as well because of, uh, less coordination. But how do, how do musculoskeletal injuries fit into cold risk?

Yeah. So I mean, the obvious one is slipping. I mean, the, the, the, the obvious one is, is, is basically, you know, um, traumatic injury where you're gonna bang yourself. So that's what people mainly focus on. But there's all these extra injuries that can occur just as, you know, from not even be able to sense fully the signals coming from the periphery. So even just this, when you think about walking, for example, where, where suddenly even walking becomes maybe wobbly, you know, a bit penguin like, and you're not moving your limbs the same way as you would be moving them normally. And, um. Which could create with time strain on your body. So there's another one that, that occurs that we tend to ignore. Uh, let's say neck pain. Uh, for example. So we were doing scans and uh, so I worked with brown fat, uh, back, sorry. In uh, 2010 there was a big fat about looking at the presence of brown fat, which is a heating type of organ in bodies and that allows, uh, the body to rewarm and mammals have it and everything everybody was, was a bit obsessed by it. And then it allowed me to see within a body how bodies responded to cold, which was pretty tremendous and was pretty amazing. 'cause obviously I actually less interested by the brown fat than seeing what muscle responses were occurring. So longest Coli, for example, is tremendously stimulated in the cold. I was amazed by it. Longest coli, the muscle in the front of your neck. Yep. Which is funny when you think about it. 'cause where does it hurt most when you're exposed to cold? And you could see it like very, very clearly. We're using, uh, a way of seeing muscle activation and you could really see these muscles fully activated. Sooz was fully activated like on your hips, which is when you're sitting down in your cold, your hips hurt. Yeah. Big time. And you get that strain, constant strain. So even the neck pain that you would get when you talk about musculoskeletal injuries is that constant contraction and increase in muscle tone that occurs from your muscles trying to protect from that heat loss. And I'm just constantly contracted and I could, I could get tremendous neck pain just from, just from that.

The part that I don't know as much about is what would be the effect on less blood flow, let's say on tendons, uh, muscles if they're active. We'll be fairly fine, but as soon as they stop the blood flow will, will kind of get away from that muscle. We also know, um, and that comes from swimmers, so again, doesn't really apply, but I wonder to what extent it could apply. Nerves are affected by temperature, which means that the speed at which these nerves operate, but also the functionality of the nerves. So one of them is called when you're swimming in cold water crab hand. Mm-hmm. Where you're basically cooling down nerves within your forearm. Uh, and these nerves will actually create a hand that will become inefficient at swimming. Right. Crab hand. So one of my students, uh, Laura Goodwin crossed the English Channel. She's from, uh, Raleigh, North Carolina. And, uh, so she was, she crossed the English Channel a few years back and we were talking about that. Effect that you get from cooling temperatures on the capacity to function. So again, I don't know how any of these would be permanent or could create to what level It could create musculoskeletal injuries, but I do know that it would modify your way of doing certain things. Sure. Right. Which would affect your biomechanics and the way your body's coordinating compensation, all that. And then you end up with compensation.

So one thing I've noticed with cold, even personally, uh, when you're out in the cold for a long time, especially in a static position, let, let's say on a sled and you're kind of zooming through, you will get these very, very intense hip pains. Okay. Is it just from being in that position and constantly fighting the sled? 'cause again, these are not perfect trails. You're going through the boreal forest, you're bouncing around, could be related to that, but your neck hurts. Like everything hurts. And we don't, uh, again, not because of helmets, 'cause a lot of people did not wear helmets, but you basically end up in a situation where you get that constant neck pain, Trapezus is being affected. All that tension that it can accumulates from kind of squeezing in. So again, these are factors even though we wouldn't call them as traumatic injuries, like, you know, tearing or whatever, these are still injuries that to me, are compounding with time. Absolutely. As I'm going through this, and I'm sure you, you've seen a lot of people with, again, back pain that are related to bad muscle tension or overcompensation.

 

Absolutely. And. I wonder too if dehydration plays a role in that as well, because I think a lot of people don't have as strong of a thirst reflex in cold conditions. But like you said, we're losing a ton of heat from our mouth and from the respiration. And with that also comes a loss of water. But what role does, uh, yeah, does dehydration play in cold injuries?

So always see dehydration or hydration as, as blood flow. Mm-hmm. Right? It allows blood to flow. So if I'm dehydrated, the first place that's gonna dehydrate is gonna be away from the core. So I'm just compounding the effect of, of the fact that I'm f fully vaso constricted, but I also have thicker blood. Right. I end up in this situation. So there, there's something interesting, uh, and I know everybody knows about this, but I, well, yeah, they, they know about the effect of cold. As soon as I get into the cold, I want to pee right. One thing that occurs, it's called diuresis, which is increased. As soon as the blood goes into the core, my blood pressure flies up. When my blood pressure flies up, I got mechanisms using the kidneys to get rid of that extra fluid. So you're gonna have a big piss once you, you're exposed to the cold. It happens in cold water quite a bit. It's more obvious in cold water. But even as you're exposed to cold and you get that vaginal constriction, you will get rid of some of the water. So you can lose, like, quite a bit of water, just even through urine. And then you're, you're sweating, so you're not gonna get this in the heat because you're vasodilated. So you don't get that loss of water, but you will get it in the cold. So again, not only am I losing through the means that you're expressing, like with the, you know, breathing, uh, into cold air.

And I'm just gonna add something to this because again, cold air is multiple levels more difficult in terms of, of, of water loss. But essentially you're gonna pee more water. So what I wanted to say, and we all know this, colder air is drier, warmer air is more humid. And we remember with evaporation, evaporation works with the delta in relative pressure, uh, relative humidity, which means the colder the air, the more water I'm losing. Hmm. Right? Because my evaporation rate is actually, I, I can lose quite a bit of, of, and you can see it as, as you're breathing, you can see that that water vapor, but my capacity, again, I can't saturate it as much, but it is creating that dryness big time. And I can see that I, that I'm losing in warmer conditions. If it's more saturated, if it, the air is warm and dry, it's perfect for us. 'cause warm and dry allows us to lose quite a bit to the environment in colder air. I'm gonna get all that, that cold air coming in. But I'm also saturating whatever I can saturate from that cold air. So you gotta remember that there's a lot of processes that are occurring there that, that do affect your, uh, your water loss. So you do need to drink. You don't feel as thirsty. You will dry the membranes by the way, the, all the, the mucus in your mouth, 'cause it is dry air coming in your nose is gonna become dry. Very important to protect from that dryness. So you would tend to put a, uh, balaclava on so you can actually order a buff. I, I like to use a buff. I put a buff, uh, all the time to be able to just cover and ke can kind of keep that more humid. So it will freeze with time. So you do need to change it once in a while. But this is something very important to remember too, like your respiratory system is very affected by this.

Yeah, that's a really good point. Um, one of the questions I'm sure we're gonna get, uh, relates to Rayons syndrome. And maybe you could speak to that real quick and explain to the audience what that is. 'cause over the course of practice, I saw a lot of patients that had rays and every time it was cold, that was really, um, fired up.

 

So Raynauds is basically an aggravated, um. An aggravated vasoconstriction where it's a severe vasoconstriction that will occur when you get into the cold and it generally occurs. It could be your fingertips. You're gonna see becoming, your fingertips are gonna become almost white. This is not a frostbite 'cause it doesn't occur in freezing conditions. It's just cold conditions. And wherever Reynolds is, uh, having an effect will basically end. So you can see it very, very clearly. You can see it on your toes. So Reynolds is an aggravated vasoconstriction. It can be painful for some people. It's not painful. But for some people it would be painful, I think as you move on through the stages, unless I'm mistaken. But as you move on through the stages, you probably get less and less pain 'cause you're probably affecting through that lack of blood flow, you're probably affecting what's happening on the skin surface. So, but Reynolds is basically your, your hand is given up. Uh, you're in a situation where you're. You have no more blood going into these areas and you're fully exposed to these conditions. So your chances of getting frost by it, your chances of aggravating are much, much, much higher. What we don't know is what is actually causing it. There seems to be some genetics to Reynolds to a certain extent, but some people develop it. When I was doing cold water diving, a lot of the women that were diving at Reynolds, uh, men seemed to have it less, but that was very impressive for me to see. Like a lot of the women that were doing the cold water diving said, I never had this and now I kinda developed it. So Reynolds seems to be something that if it's not coming from a genetic origin, that is something that you can create through increased vasoconstriction. And it's probably a way of your body saying, okay, I gotta protect myself 'cause you're exposing me to the cold all the time.

So just one more thing to think about too. 'cause your fingers will literally, they call it waxy appearance and it, it literally looks like a white candle. Like it just has a, a weird texture and appearance to it, but something to watch for and may be something that people want to see their doctor about. If, if that's, uh, something that they've experienced in the cold. A hundred percent. I, I think one thing is if you have Reynolds, you need to document it. You need to look at the, is it gonna get worse? You know, talking about that baselining. One thing we're putting together right now is arctic readiness assessments, which is basically looking at these, this damage in the periphery and to be able to, to see what's gonna happen when people come back from cold conditions. So for me, if you have Reynolds, you do need, and that's what I told people last week as they were wanting to go into ice water. When I saw a few people with trench foot, I said, you need to document this. These things need to be documented. 'cause again, it affects dexterity too, like that waxy thing. And you barely, you're barely able to manipulate and you got a lot of issues, uh, you know, doing even fine motor skills.

Absolutely. Well, speaking of the cold weather checklist, what are some things that people can take away from this conversation that they can put into practice so that they can either start preparing their body to handle cold better, they can be prepared when they know that the conditions are gonna be cold, so that they have a good pack list. Uh, what are just some real practical takeaways?

 

So, one thing, and, and we can even share this, I'd be happy to share it. It's kind of the model that we've, that, uh, I've helped, uh, people from science to perform to create, which a lot of them are soldiers, like they, they work with in the military. And what we did to make it very practical is we created a triangle. And this triangle at the base is your basic body needs. So you need to worry about. Do I? Am I sleeping well? Am I eating well? Am I dehydrated? Am I overly stressed? Do I have any type of injuries? This is basically what my body needs from the get go. So we start with this. This is my bottom line, and this applies to many, many different things.

The other component is what I call adaptability. And adaptability is something you train, you train for. It's a little bit like we were saying, trying to use gloves in cold conditions and manipulate stuff in cold conditions. You need to practice these things. So this is what I call adaptability, and again, it comes from soldiers where adaptability is your capacity to operate in any condition without risks or reducing the amount of potential risks, and, uh, understanding fully what is going on, knowing what to do. And this is a tremendous. This is extremely important to develop, and this is something that sometimes we don't take the time to do it, but to me, I have my basic needs. I, I meet them. I still need to learn how to operate in these conditions.

The other part, uh, so the other part would be self-awareness. And we don't like to talk about this, right? A lot of people think they're tougher than self-awareness. Just remind yourself that some of the toughest animals on earth are tremendously self-aware, and this is why they survive. Self-awareness is your capacity to detect what is going on. It's your mind. It's your mind. Essentially, your bo your body's needs is your body. Adaptability is the environment and your self-awareness is your mind. And your mind is actually the glue for all of this. It means that on a regular basis you need to check with your sensors, your body's sensors, which is exactly what animals are using. You know what's amazing with animals is you got something, people call it instinct. Well we could call it intuition. It depends how much level of consciousness you wanna give animals. 'cause I do think animals also have intuition. So, but some people call it instinct, but that instinct can only be developed if you're fully self-aware. If you're just doing things and disconnecting your head from your body, you're gonna get in trouble.

So I think for me, one of the major takeaways is you do need, of course, have the right protective equipment. You need to know to have a very good plan. You need to understand the effect of temperature, the effect on thermo regulation and all these things that we've talked about. But the part that is key is to develop a self-awareness of six sense of you understanding. And the Norwegians call it embracing the cold. So at the NATO Excellence Center for Arctic operations, the one of the commanding officers, I was in Arlington at a NATO meeting with him and he said, soldiers must must learn to embrace the cold, which means that you become one with what's going on around you. And this is something to me that is beyond just figuring out the checklist for basic needs, the checklist for, okay, this is my equipment and everything. The other part is developing that sixth sense that you almost know what's coming. I'm looking, and this is again, working up Norman Natives. They did have that sixth sense. Some days we're hunting and then the next day we're not going. And you go. Why am I not going? They go, uh, no, it's not good day today. And you have no idea why. And then it starts snowing and you go, holy crap. We would've been caught up in that zone with, and we wouldn't be able to see, we would've frozen probably. So the guys were able to make decisions, which I don't know how they made it. I don't need to know. The only thing is that it kept us, uh, it kept us safe. So I think that part which is the mind is not something we should underplay and it's something we should thrive towards and not just thrive through going through a checklist and saying, okay, I got all of this done, which is super important about my, my basic body needs, and looking at my training. But I wanna develop these skills. And I think as a leader, you wanna develop these skills for people that are coming through and teach them how to develop these skills. Failing to plan is planning to fail, right? And I mean, if you do not have a plan when you're approaching cold weather, it can, it can get bad quick. Um, yeah. Know that for sure. You put emphasis on it in the heat, right where we're gonna go, okay, we've got water. We're gonna take water every hour. We've got all this planned for heat. 'cause we're traumatized and we're scared of heat. I fully understand it. It is tremendously dangerous. As you start hitting these super high temperatures, you are in danger big time. But we should do exactly the same thing for cold and, uh, so cold is a big deal.

The other thing that, that happens in cold that people probably don't know. So in the military they do talk about this quite a bit. It's called the golden hour. So if anything happens, Dr. Uh, you know, traumatic injury, very important injury in the heat, you do have that golden hour, which is an hour that, you know, you, you have room to maneuver in the cold, especially at, in arctic conditions, you do not have that time. You don't have that time, which means that anything has to be planned to the.to be able to save somebody's life. That's how, that's how extreme cold can be. You do not have that time and anybody trying to help out can actually themselves get injured by cold. So even on the medic side, trying to face these cold conditions, there's so many challenges, so many, so many things can go wrong compared to what happens in the heat. That you gotta be super careful and tremendously well planned. That that was a great summary of the safety related to cold.

Let's now shift gears and talk about how we might be able to leverage cold, uh, for recovery. So, I know a lot of people, they may have an injury and so they put ice on a sore knee or you know, cold plunging has become pretty popular. It's something that I do at least once a week. I'd love to talk through what the science says about using cold as a modality.

 

So, and again, you can correct me 'cause I think you actually, your knowledge in this is even greater than mine when it comes to injury. Um. Inflammation is actually protective. Like inflammation is not a bad thing. We don't like it 'cause you know, it kind of reduces range of motion. And we do put on the, when the traumatic injury occurs, you do put ice on it to try to reduce some of the pain, but also kind of get that inflammation and swelling away. A lot of the approaches chronically is to go towards heat and increase blood flow, right? Absolutely. So for me, absolutely. Yeah. So for me, that whole concept of, you know, putting ice and leaving ice and all this stuff does work to a certain extent to deal with what we're talking about in the first few minutes of that injury. But chronically, you do want to promote blood flow to that region to be able to, to, to allow tissues to, to repair. So that's one factor.

So now people say if it works for local, it must work for the whole body. So why just put my elbow in when I could throw my whole body into the ice water and it's gonna fix it all? So research says that it's not convincing at all, that it's improving the inflammation response at the whole body level. So there seems to be, I've seen 10, uh, to 10 F alpha changes. Like there seems to be some improvements in anti-inflammatory markers. But again, what is the actual effect of this? Uh, very hard to say. Like, I don't know if you know, if it really makes that much of a difference. And most of the work that I've seen was not in ice water, it was actually in warmer temperatures. So again, we gotta be careful when we talk about ice water. It's the most extreme. But there's all this range of water temperature below 31 degrees Celsius, uh, which is 80 Fahrenheit, I think below 31 degrees Celsius. Uh, we're thermo neutral at 31, which means anything below this is cold. There's that whole range. You know, again, we don't have data for that whole range and we don't know what that whole range does to inflammation. We're obsessed with ice water, so, but in ice water it's not convincing at all. So, so we're not sure about the inflammation response.

The immune response was the other one that people brought up. So the immune response, you gotta be careful about the immune response 'cause it does respond to stress. Also, ice water is a tremendous stress. So again, people have looked at changes in white blood cells and say, white blood cells change. So it must be good for you. Well, no, generally you respond to infections. You know, when, so the best way would be to infect somebody, which ethically is not their best way to do research. So we don't really have a good feel for the effects of on, on the immune system. And again, why do we need to talk about ice water When we could talk about, you know, water that is more comfortable, which is still cold and still having an effect, but not to the extreme of creating a, a tremendous stress.

So. On the biological side for the positive. We do get a release of endorphins. We get a release of dopamine, which is again, very good pain reduction, feel good hormones, uh, activation through catecholamine. So catecholamines are gonna increase my arousal. And I'm, you know, it's kind of taking a shot of caffeine and I'm feeling awesome about it. So that is clear that it's occurring with, with cold water, psychologically. This is, I think, where the benefits lie in my mind, which is, uh, when I go into cold water, it kind of makes me feel good. And I've always asked people this, and it was funny, I was giving a workshop, uh, to special forces in Switzerland and I said, what's the most important thing about cold? 'cause they're do, they're doing it for after exercise. And I thought they were all gonna say recovery, muscle recovery, right? And they go, 'cause it feels good. And I go, man, perfect answer. Now, at the end of the day, do I need to know what it does? Uh, on the recovery side, by the way, the literature seems to be convincing that it reduces blood flow and it's actually not promoting proper recovery of muscles. So there's nothing proving that it actually improves the recovery of muscles. People have been using it and saying it, but again, it's not based on anything that is supported right now. Um, so these are the effects.

Some of the other effects, again, I don't know if you eyes dip or cold dip with other people, like you go with buddies or friends. Yeah. So there's kind of that social aspect of it being in a nice climate. So the, the green blue effect is tremendously important. Like it makes me feel good sense of belonging, sense of community. For me, this is all positive on the risk side. Again, we forget about the risk of if I do this every single day, I will develop non freezing cool injuries. And I've seen it multiple times in people. A lot of these, uh, Wim h instructors that, uh, think that they can defy nature, uh, mother nature will kick your ass. Yeah. So at the end of the day, you end up in a situation where you will develop non freezing cold injuries, uh, systematically from these repeated exposures. Uh, so there is that risk.

 

As you also know, especially in ice water, it is a vagal shock. It is changing blood pressure tremendously. There is a risk of cardiac arrest. So every time we've done stuff, when I was doing it in Finland with soldiers, the had medics, uh, in place the had, uh, defibrillators in place just in case there was fibrillation and people would end up, uh, in cardiac arrest. And also if anybody has cardiac issues, not, not the best idea to jump in ice water. So, and you look at a lot of these gurus that are putting people in water and putting people in ice water, no formal training, how to deal with any type of these extreme conditions. So again, what I say to people is there, the only perfect guru in this is you. If it doesn't, uh, when we used to land planes, if it doesn't feel right, sound right, or we're not down by the first or the runway, I'm gonna put full power and stay in the air. Same thing. Doesn't feel right or something doesn't. You look at it and you go, something's off here. Don't do it. It's as simple as that. I'm sure you would give the same advice for training. You know, if it, if it's hurting, yeah. You might not be the right exercise right now for you. So, so for me, these things, but it became a bit of a fad right now. And I would say social media has created a hype that is immense. I thank Wim H for the, all the interest that he brought to cold and to cold water. This has been tremendous for my career and I thank him deeply for this. I think he's an amazing man. What he's been able to do, how he's developed this, um, I think some people have taken it face value and when you say two minutes in ice, water is good, people will do 20 minutes 'cause they think it's 10 times better. Uh, that's not how physiology works at all. And you know, the initial idea, even within the Wim Hoff world was two minutes for me. We stick within that two minutes, we go through the cold shock, we regain control. Of her body, which is regaining control of a very, very high stress and our very nervous system through breathing. Amazing work done by this group. You know, teaching people how to regain control. You do your two minutes, anything else is taking you to hypothermia and there's no real benefits once you come out of the water.

You gotta always have to remember that there will be an after drop as your blood flow will, as your, uh, vessels will vasodilate. Cold blood will rush in, right? And I'm gonna get that after drop. So always stay with people. Never let them kind of go back and do whatever. Stay with them. Have strategies to rewarm, uh, always work in a buddy system. Tremendously important. You don't do these things alone. But I think there's just like, we're thinking about safety with workers that, that, that whole fad is creating a safety, has created a safety risk that is tremendous. From lack of understanding and from people that have become experts in cold with no formal training.

Yeah, no, that's, those are all tremendous recommendations. My personal experience has been, again, not quite sure how it benefits me on a day-to-day basis, but psychologically, uh, I go with my wife. Um, we try to do one time a week, we live close to the Puget Sound, so the water temperature's about 48 degrees Fahrenheit and we. Generally shoot for like four to six minutes. We do breathing exercises, uh, while we're doing it. And then every time we finish, we're like, never regret doing it. We, we just always feel better. And so I, I, I think, you know, you're out in nature, you're looking out, and I find a tremendous benefit from that perspective. But from a physiological standpoint, uh, it's, it's hard for me to know what those benefits are, but it's, it's definitely become part of my weekly practice.

Yeah. And I mean, you know, I practice yoga, I practice meditation. I've done a lot of these practices. For me, it becomes a bit of a tool. Cold is a tool for training. It resets my nervous system, so it kind of creates that high stress. I regain control and it's almost like I feel way better afterwards, but even if I don't measure it, let's say I don't because we don't need, like Einstein used to say, not everything that can be measured should be measured. What difference does it make? What you just described to me is the essence of everything. Like the essence is you feel better. Do I believe in it? Yes. Do I think it could actually benefit some of the workers that work in cold weather tremendously. Again, it's, it's one tool amongst many other tools, and maybe it allows me to, when I face cold conditions, I know how to regulate myself. For me, I know it helped me quite a bit to regulate, like I can regulate much, much faster when I don't do it. It's almost like I need to retrain it and it, it, I think it's an amazing trainer for the mind. Do I need to know exactly what it does biologically? Do I need to know about the immune system? Do I need No, I, I don't need to know about this. So even though as a scientist I could measure it, what difference does it make? Maybe it means something else. Uh, something different to you and what difference does it make? I will say too, that I feel like I'm better able to handle colder weather.

Like it, it probably has helped me with that adaptation, but I think mentally it's helped me just from a grip perspective. It’s just one more tool in your tool belt where you can say, okay, I’ve done this hard thing and got through it. You are in control in that environment. You can get out whenever you want, go to your warm car, drive home, and it’s all about making the right decisions.

When you talk about acclimation to cold, there’s a very interesting study by Dr. I. Goma Gavic from Slovenia that showed heat acclimation actually increases blood flow to the periphery and is a better way of acclimatizing to cold than exposing yourself chronically to cold and creating damage. Sauna, for example, is a better method because it increases blood flow compared with being cold all the time. For me, it’s about finding that balance. Healthy bodies aren’t made to be linear. It’s not one thing that fixes everything. It’s the balance of multiple strategies together.

At the end of the day, it needs to feel right. Like exercise, if I’m not working towards performance or trying to perform at my best, why would I do something that really hurts my body? Making the wrong choice doesn’t help anyone.

The biggest mindset shift I’d share about cold exposure is this: you are the only expert on how your body reacts. You need to speak up when you’re being affected. You have the right to protect yourself and prevent injury. If you don’t say something, nobody can help you.

There are so many key takeaways here. People working outdoors often don’t know where to start or what to trust, and translating complex science into practical advice is what makes this guidance so valuable. If this episode helped you think differently about cold exposure, recovery, or performance, consider following the WorkReady Podcast on your favorite platform. These conversations give you the best from science and sports medicine to help you excel in the field.

We’re also continuing this discussion inside the WorkReady Community, diving deeper into cold exposure, recovery strategies, and performance. The community is free and a place to connect with peers and share best practices so everyone can stay safe and healthy on the job.

Until next time, remember you are worth investing in. Take care of yourself, take care of your people, and stay work ready. Thanks so much.