Carbon Dioxide For Hikers And Mountaineers

In this episode, we explore the idea of carbon dioxide tolerance training for hikers and mountaineers.

You will learn:

• What carbon dioxide tolerance training is (and the theories on why it can be beneficial for exercise performance)
• The potential benefits of carbon dioxide tolerance training for hikers and mountaineers
• Can carbon dioxide tolerance training help with high-altitude acclimatisation, reduce the risk of altitude sickness or improve high altitude exercise performance?
• How to test and track carbon dioxide tolerance
• A few training approaches that can help improve carbon dioxide tolerance (and my opinion on their application for hikers and mountaineers) 

What Is Carbon Dioxide (CO₂) Tolerance Training and Is It Beneficial For Hikers and Mountaineers?

​Mentioned In The Episode: 

Breath Hold Training For Hikers And Mountaineers 

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Episode Transcript:

[0:00] Right, hello, hello, ladies and gentlemen. So in today's episode,

[0:03] we are going to be talking about carbon dioxide for hikers and mountaineers. And we're going to be diving into this subject, which is becoming a little bit more and more popular. And we see more blogs and videos and people talking about this particular thing and just explore it, give you a bit of context, what it's all about and how it may relate to mountaineers. Now, you may have seen this subject come up because it has been getting really, really, really more popular in the last probably be two years in the hiking and mountaineering community. And you may have come across people talking about carbon dioxide tolerance training or chemo sensitivity or something like that. Now, to be clear from the get-go, and just want to talk you through my intentions for this episode, I don't think training yourself doing this carbon dioxide tolerance is the worst type of training in the world. I think it's a pretty interesting subject, and I think it may be useful for some people in specific circumstances. And this episode is not designed to kind of trash this area of training or anything like that, but I am going to be critical of it because I truly do think there's just a lot of hyperbole around this type of training out there. And a lot of the people who are talking about this online are just taking it a bit too of a step far.

[1:17] And it's kind of turning this thing where it could be pretty cool, and they're saying it's the best thing since sliced bread or whatever it may be. And I think it is important to have a bit of a counter argument out there, a bit more context, a bit more nuanced to all of this. Why? Well, as I said in a previous episode, this is something I'm going to be doing this year as the whole concept of AI summaries is a big thing. And when you type in something to Google or chat, GBT, whatever it may be, it spits you out answers. the way these things work is they'll essentially look at all the available information online and just kind of take the average of what that is and summarize it and say that's right. And if every single person online, the only people who are talking about this is saying, hey, this is the best thing since sliced bread and it does all of these, that's the only information out there.

[2:05] Well, when these AI things are taking all that data, it skews it a little bit more. So today we're just giving a bit more context, a little bit more nuance as we get into things.

[2:15] Now, admittedly, this is a very, very niche subject, but if you are interested in breathing training, which I know a lot of hikers and mountaineers are, you may have come across this before.

[2:24] And the tricky thing here is, yeah, just because I guess it's new and exciting, the people who are learning about this, teaching about this, coaching about this, they're all really, really, really, really positive about it, which is cool. But again, a lot of what people are saying is a bit hyperbolic. And I don't think there's anyone really giving a more balanced view in the hiking community or the mountaining community that I've seen. So essentially what we're going to be diving into today, we're just going to explain what, it's all about. Why are we talking about carbon dioxide? What is carbon dioxide tolerance? What is chemosensitivity? Why carbon dioxide tolerance training is recommended to many hikers and high-attitude adventurers? How to develop and go about this type of carbon dioxide tolerance? And just explore this in a little bit more detail. So let's start with the basics. What is it? What are we talking about here? Now, carbon dioxide, most people are pretty aware, it's part of our breathing cycle. When we breathe in, we breathe in oxygen. When we breathe out, we breathe out carbon dioxide. Now, for long people, people didn't really care about carbon dioxide. Most people focused on the oxygen, said, look, this is what we need to fuel our muscles, yada, yada, yada.

[3:30] More recently, people have begun to explore the relationship of carbon dioxide with our breathing, with our performance, with our health, and all of this. And essentially, the understanding now is carbon dioxide isn't just a waste product, isn't just something that's a waste product as part of our breathing. It's not just something we breathe out, and that's really all that happens. But it actually does impact and plays a pretty significant role in our breathing cycle. And it plays a big role in regards to our breathing rates and our desire to breathe. And essentially, what tends to happen is as carbohydrates, as carbon dioxide in the body builds up, this will trigger our breathing to get a bit quicker. And we'll start breathing, breathing, breathing, breathing, breathing to try and get rid of that carbon dioxide.

[4:14] That tends to kind of be kind of what's going on now this leads into why carbon dioxide tolerance is recommended for hikers and mountaineers and why people talk about carbon dioxide so much for hikers and mountaineers well there's two real main reasons why people often recommend this or say it's beneficial to think about this and train this number one as we sort of said our breathing is driven primarily by our carbon dioxide levels as we exercise so we're hiking we're climbing whatever may be, carbon dioxide builds up. So therefore, our breathing gets a bit quicker.

[4:48] Now, for some people out there, they are a bit sensitive to this process. They are a little bit sensitive to this carbon dioxide. So what can happen is we can just start doing a small amount of exercise and all of a sudden our breathing gets really, really quick. And there are a lot of hikers and mountaineers out there that realize, hey, the second I'm kind of happy walking along on the flat, the second I hit an incline, I get really, really, really out of breath. So people say, well, it may be because of this. It may be because you're sensitive to carbon dioxide, and that trigger and reflex to breathe quicker is coming on for you a little bit quicker. So the idea here is if you can train yourself to better tolerate carbon dioxide in the body, to reduce our body's sensitivity to it building up, we can therefore exercise more.

[5:36] Accumulate more carbon dioxide before our breathing ramps up quickly. So therefore, we can move quicker, we can do harder things before the breathing becomes an issue, which obviously sounds pretty good.

[5:47] Now, the other sort of side effect of this, of what people kind of talk about, gets a little bit more sciencey, is they talk about this thing called the Boer effect, if I said that right, B-O-H-R effect. And essentially, it's all about how carbon dioxide can affect our hemoglobin's affinity for oxygen. Now, hemoglobin is what carries our oxygen in our body. And essentially, what this whole thing is, is when carbohydrate, carbohydrates, I keep on saying this, when carbon dioxide is higher in the body.

[6:21] Hemoglobin will actually release more oxygen to our tissues.

[6:26] So it carries a bunch of oxygen. If carbon dioxide is lower, it won't release quite as much. If it's higher, it'll release more. So therefore, our tissues, our muscles get more oxygen, which is pretty cool. So therefore, the thought process is if we can train our body to tolerate carbon dioxide more, if we can hold onto that carbon dioxide a little bit more before we have to breathe it off, this will therefore help our hemoglobin release more oxygen to our muscles and therefore help us with exercise, which sounds pretty good as well. And that's kind of the theory those two things reducing us getting breathless really quickly helping us get more oxygen to those working muscles sounds pretty cool and in theory that makes sense because if we can sustain a higher level of exercise before our breathing starts to get out of control or at least starts to get uncomfortable that's a good thing that's a good thing in regards to comfort that's a good thing in regards to enjoyment that's a good thing in regards to performance and if we can get more oxygen out of the actual oxygen we're breathing meaning more of that oxygen we're breathing in gets to the working muscles, that's probably a good thing as well.

[7:30] So in theory, that all makes sense. And looking at real world performance, if we're like, you know, getting out of the theory and saying, how does this apply? It seems relatively safe to say that people who perform better at endurance performance, so, exercise that you're doing for long periods of time, hiking, mountaineering, whatever it may be, it's relatively safe to say that people who perform better here have a lower sensitivity to carbon dioxide, have a better tolerance to carbon dioxide. There isn't a huge amount of studies that look at this directly. There's still a lot of question marks around it, but it's relatively safe to say that.

[8:07] This is where people kind of go off the rails a little bit with this in regards to how they talk about this, how they present it, how they sort of share this with the world. Because the next step in the conversation, people say, okay, Better tolerance, carbon dioxide will do these two things. And the next step in the conversation is people saying that, okay, if we want to improve our carbon dioxide tolerance, we need to do this specific type of training, which will improve that. And therefore that will automatically improve our hiking, our mountaineering, our endurance performance, our performance and attitude or whatever may be. But it isn't quite as simple as that. And this is what a lot of people, I don't know whether they just don't communicate so well, whatever it may be, because there is a link between these two things. There's a link between our sensitivity to carbon dioxide and endurance performance, but it doesn't mean that this is causing the performance. There's a link, but there doesn't seem to be any evidence to say, hey, this is because of this. There's probably a dozen, two dozen, three dozen different things that are going on simultaneously.

[9:15] There seems to be a link between those two things, but there isn't any evidence that I've seen that if you do a specific training for carbon dioxide tolerance, that therefore you'll improve your endurance. I'll say that again. There isn't any direct evidence that I've seen that if you actually go through specific carbon dioxide tolerance training, it will therefore improve your endurance.

[9:39] Rather, what the evidence shows, or at least the stuff that is available at the moment, is they look at people, they look at a bunch of different people, and they say, okay, out of 50 people or whatever it may be, hypothetically, 10 people are super, super, super endurance fit. 10 people are kind of endurance fit. Some people are average fit. Some people are very, very poor fit. And they've kind of said that, okay, the people who are super, super fit, There tends to be people who have better tolerance to this. That's kind of how they're looking at it. Not so much if you do specific training, you will improve your endurance performance, but more people at the end who are better, more fit kind of have this tolerance, which is interesting. And it is very, very important in this context because it suggests that something in normal endurance training, something people are doing to become better at endurance sports and better at endurance performance will improve carbon dioxide tolerance.

[10:37] So something in a normal training program that they're doing will improve this. Now, one study looked at this, and admittedly a pretty small study, and it's only one study, so you can obviously take this at a grain of salt. But they theorized that this may come from endurance athletes. Just having repeated exposure to high rates of breathing occurred during exercise. So when you're doing like harder exercise and you're breathing heavier and you're just doing this more and more and more. And they theorized that just because they're practicing this, they're doing this, the body is adapted to better sustain these high outputs for a long time. So they did some specific breathing training, which simulated this. So they essentially got, I think it was like people did 30 minutes of maintaining very, very high ventilation, where they were just breathing quite heavily for 30 minutes and did that for a long period of time in a very specific technique, whatever it may be. And they saw improvements in sensitivity, which is only one study. It's immediately small, but it kind of makes sense. If you're exposed to something, if you're doing something and you challenge the body in a progressive way, it'll probably get better at doing that thing. So with all that being said, you might be like, okay, Ron, yeah, cool. What does this mean? Well, when you hear people start talking about, hey, how you should replace your cardio with breathing training and it will see you with great results, or saying that cardio won't improve your breathing or won't improve your tolerance to carbon dioxide or won't improve this or won't improve your breathlessness.

[12:00] Yeah, maybe take that with a bit of a grain of salt. Because I would sort of argue on the other way that there doesn't seem to be much evidence to show, at least that I've seen, that doing specific direct breathing training will improve these things, but rather the evidence points something's in endurance training is helping with this.

[12:20] To some degree. So yeah, it's interesting. Not to say, again, this type of stuff is bad. I'm not ragging on the carbon dioxide training at all, and we're going to be exploring that in a little bit, but it seems like just normal endurance training improves this in one way or another.

[12:36] And in all honesty, even though a lot of hikers and mountaineers out there do some training, they're active, they get out on the trail, they do some stuff in the week, whatever it may be, very, very, very few people are really following an effective, structured, progressive endurance training program. Very, very, very few people are kind of covering their bases of low-intensity exercise, high sustained stuff, progressing it over time, and this and that. And realistically, sometimes people just kind of get obsessed about these little things and they miss the ground basis of just following a good training program. Because not only will that potentially improve this specific thing,

[13:11] but it'll have so many other carrier effects as well. So if you're interested in this subject, I would probably say that's your first place to start.

[13:20] So next up, what about high attitude? How does that relate? Well, obviously high attitude, a lot of hikers, mountaineers going up there. Obviously high attitude affects our breathing. We go up to high altitude, our breathing increases as part of acclimatization. As we acclimatize, the breathing kind of steadies a little bit more. It is generally accepted that kind of maintaining a relatively slow, steady breathing rate when you go up to high altitude is going to be beneficial for your blood oxygen saturation, as opposed to getting really, really, really hyperventilation all the time. A bit of hyperventilation and quicker breathing is important for acclimatization, but you know not getting completely out of control so it's generally accepted if you can do slower breathing rates it's probably going to keep that blood oxygen saturation a little bit better, so again it kind of makes sense that developing your ability to keep your breathing steady reducing your sensitivity to carbon dioxide which will ramp up your breathing that that will be useful but then again this is kind of where people sometimes just go a little bit too far and get carried away with promoting this type of training because they all sort of say that okay.

[14:28] Increasing our carbon dioxide tolerance will reduce our risk of altitude sickness. It'll speed up acclimatization. It'll improve blood oxygen saturation. It'll enhance your performance. And they'll say all of these things, but there isn't any really direct evidence to show any of this is true. Like, yes, and this is kind of what people do. They will use a logic chain saying that, look, if you do this training and you improve your carbon dioxide tolerance, you will therefore maintain a slower, steadier breathing when you're at high altitude, which will therefore, it might maintain higher blood oxygen saturation, which therefore may increase, reduce the risk of attitude sickness. And logically you can go through all of those steps and like, yeah, that goes into one, goes into the other. And I get it. That makes sense. But high attitude, it's not simple. And we really can't make assumptions like this, or even these chains of logic, they just don't work with high attitude. Because if you put this into perspective, you could do literally the exact same thing with improving your fitness. Logically, you could look at the same chain of events. You could say, if you improve your aerobic fitness, you will maintain slower and steadier breathing because you're not out of shape as much and you're slower and steadier and going a little bit better. You will therefore maintain your higher blood oxygen saturations and therefore you would reduce your risk of attitude sickness. You could use that exact chain of logic of just improving your fitness.

[15:48] But there is no evidence to show, and this has been looked at a lot, to show that increased fitness will directly affect your risk of altitude sickness. The logic doesn't always hold up with high altitude. So we do need to be intentional here. And when we're talking about this, there just needs nuance. So if anyone's just trying to say, hey, this is going to be a direct thing, which will dramatically make a difference to your risk of altitude sickness. And they kind of use that hyperbolic language. You need to take it as a grain of salt. Again, I don't think it's a bad thing. It probably will help you or whatever it may be. but we just need to be careful about how we communicate this.

[16:25] So with that all being said, now we have a little bit of context, a little bit of nuance. What if you are interested in this topic? What if you're like, okay, cool, Rowan, that makes sense to me, but this interests me. I want to do this. This appeals to me. Maybe I'm already doing a good endurance plan. I'm confident I'm covering that base. I'm confident I'm getting all the benefits from just good, solid endurance training. And I want to do something extra. And I want to get into this. What if that's you? Well, let's talk about it. And we'll just get into talking about specific testing and specific training. So first up, if you are looking at this type of thing, usually the first place people start is doing a little bit of testing, getting a little bit of insight into cards to what their carbon dioxide tolerance is like, whether it is really good, really poor, something that needs to be improved on, or whatever it may be. So typically when people are talking about this, they will talk about two different tests that I've seen.

[17:18] They'll talk about the BOLT score, which we've done a previous episode on, and they talk about the carbon dioxide tolerance test. Now, the BOLT score, just a quick recap on that. This is a really, really simple thing where you're kind of doing like a breath hold to judge or get a score from this. How you do it, you're just kind of sitting down, you take a normal breath in, normal breath out. On the exhale, you're just going to hold your nose and you're just going to literally time how long you can hold your breath. But we're not doing a max test here where you do literally as long as you can, but you time the number of seconds you feel until it feels the first desire to breathe or the first stresses of your body urging you to breathe. So you hold your breath after the exhale until you first want to breathe again. And then however many seconds you do that, that's your score.

[18:09] And we've done a whole episode talking about this before, but it's basically, you know, people kind of give you pass, fail grades, whatever it may be. I don't particularly love that, but that's that test. Now, the next one is the carbon dioxide tolerance test, which is relatively similar. So, essentially, this one, what you're going to do is just take a few breaths. On like the third or fourth exhale, you're going to basically take a really, really, really big breath in, nice and full, nice and deep. You're going to start a timer and essentially just begin a really, really, really slow exhale through your nose. And you just do as slow as you can. And essentially, you just keep on exhaling as slowly as you can until your lungs are completely empty. So you've got nothing left. Then once your lungs are empty, you stop the timer, and that's kind of your score. So these are two things that people will often say online, say, hey, these are good tests for this. You know, are these tests perfect? No. Is there a huge amount of evidence to support them as like really accurate predictors of saying, hey, if you score low on this, your carbon dioxide tolerance is rubbish, whatever it may be. No, you know, there's a little bit debate on that or whatever it may be, but they're good enough. They kind of do the job. And, you know, for most people that don't have access to labs or proper testing, whatever it may be, these are probably as good as you can get.

[19:25] Probably the best way I would say if you're using these assessments, I don't really like when people sort of say, hey, these things, you score this and you've got poor or bad or good or pass or fail, because these things, they're not massively scientifically validated. There isn't like clear cut evidence saying, yes, these are very, very accurate predictors. And if you score this, this is a very clear sign saying you're poor or whatever it may be. I don't really like that. But instead, it's more, I would recommend using them as a measure of progress. Where basically, if you're interested in this type of training, you do one of these or both of these to start. Then you do whatever practice, whatever training you want for three or four weeks, then test it again. See if it's improved. Then do your training for three or four weeks, test it again, and use it as kind of a measure of improvement as opposed to like a pass-fail thing. I know other people would sort of like argue that, but that's kind of how I would more lean towards it.

[20:22] Now, next step, once you've tested, then you might be like, okay, how am I going to improve this? What can I do to improve this and train this? Well, there's four things that are commonly recommend.

[20:31] I'll kind of talk you through them from most simple to most complicated. Most simple and first place most people probably want to start is doing nose breathing. So essentially breathing in and out through your nose. The idea behind this is when we're breathing in and out through our nose, it kind of slows down our breathing a little bit. And in this context, we'll create a little bit of extra carbon dioxide buildup. So therefore the body will get used to this. It'll better learn better to tolerate it. It'll get less sensitive, this and all that. So you may start doing nose breathing just at rest, just doing around the home. You may start applying it to someone just walking around the local neighborhood. You may start applying it to load a pack walking or hiking or whatever it may be. I often talk about nose breathing for my hikers. I love this. I use this with most of my hikers, not specifically for this reason, but for a bunch of other things like more of a measure of intensity. So this is a really, really simple thing. I would sort of say two thumbs up, I like it, and go right ahead. Only thing to be clear with this type of thing, and a lot of people miss this with the nose breathing stuff, this is for low intensity, sometimes moderate intensity exercise. If you're doing interval training or high intensity stuff, don't worry about this. It's not really sustainable. It's not really doable. This is gentle, lower intensity, walking, easy hiking, whatever it may be. That in itself, very simple, but it can begin this journey of building up a little bit of carbon dioxide and helping you feel a bit more comfortable.

[21:57] The next step, and this isn't really like a progression, you can kind of do this at the same time, is doing what they call the breathe light exercise, which anyone who's talking about this stuff talks about this. This is a really, really, really simple exercise or simple process where you're just intentionally slowing your breathing down. So going a little bit slower than you would kind of naturally feel. The idea behind this is you may just be sitting, you can do this exercising or whatever, like while you're walking, but essentially what we're doing is we're slowing our breathing down, focusing on diaphragmic breathing, feeling like our belly's going in and out. And we're kind of thinking of small, shallow breaths. So we're not having big, deep breaths or whatever it may be, but relatively small, shallow breaths. Aiming to be slow, aiming for relaxed, and then kind of aiming, you know, if you were timing this over the minute, we would be looking at anywhere from six to 12 breaths per minute. So quite very slow. And obviously that's a bit of variation, but that's what we like. And what we're chasing here is as we're doing this breathing, we're chasing getting a slight urge to breathe. They call it air hunger.

[23:04] The slight urge to breathe. And you're like, I kind of want to speed up my breathing. But what you're doing is you're resisting that urge to breathe more, and you're kind of just managing that. And you may start this just standing around or sitting down. Then you may apply it to walking around the home. Then you could apply it to walking around the local neighborhood. Then you could apply it to hack walking and hiking. And again, this is kind of good stuff for low intensity, moderate exercise, but I wouldn't really say this is higher intensity. So we've got our two things. If you want to like specific video instructions and someone explain that a little bit better, just go into YouTube, type in Breathe Alive. There's a bunch of people pop up and that's easy enough. So, they're two simple ones. The next level to this, and this is one that some people would build up to, is doing breath hold training. Now, in all honesty, I'm very so-so on this.

[23:56] I personally don't think many people need to be doing this. I don't really incorporate it for my people, but it can be an option for this. Essentially, breath hold training in its most simple term is essentially practicing holding your breath after an exhale. So essentially, you may be sitting around, you may be walking, you may be exercising, and essentially you breathe out, you hold your breath. This can go from anything from mild where you just do it and you feel first urges, hold on a few seconds and then relax. Some people do this like very, very intense or whatever it may be. And the idea behind this is essentially we are holding our breath, letting that carbon dioxide build up because we can't breathe it out. And if we're applying this into exercise, we are building up more and more and more and more and more.

[24:41] Does it work for carbon dioxide tolerance? Probably. But I don't really like it in the sense that I think a lot of people kind of get, no, I'll rephrase that. I don't like dedicated training time to this in the sense of saying today, I'm going to do one of my sessions and it's going to be breath hold training. I'm going to go do a walk and this is going to be the focus. I'm going to hop on the treadmill, do sprints. This is going to be the focus or whatever it may be. I think there's just so many better ways of applying your time and effort in your training than this. I don't mind this is if you incorporate this, I guess, a bit more casually into other things you're doing. So for example, if you're just walking around the neighborhood, maybe you do like walk the dog every day. You could do some of this while you're walking the dog. You could do this while around the grocery store. You could do this at home. You could do this when you're just doing like your pack walking sessions or whatever it may be. So if you layer on top of something you're already doing, I wouldn't say I quite like this. I don't mind this, but I wouldn't personally do dedicated sessions to this. If you were doing higher intensity sports, maybe, where you really, really need to build up that ability to perform when you don't really have breath, maybe.

[25:53] Maybe, but for hikers, mountaineers, probably not. Now, some people might argue that perfectly fine. That's my opinion. The final thing that a lot of people recommend for this type of training is using an elevation mask. So if you haven't seen these before, they're kind of like gas mask-y things you put on during exercise, and it basically puts resistance for your breathing, while you're exercising. Now, a lot of people used to talk called these like attitude masks. You've seen marketed them. They have nothing to do with attitude. They're called elevation masks now, and one way people use these is for this carbon dioxide tolerance training. Now essentially the way this works is it just restricts the breathing so it makes things tough and then essentially because there's a little bit of space between your mouth or your nose and.

[26:37] The nozzle if that's the word carbon dioxide kind of builds up in that space so when you're breathing you kind of get a little bit more of it. Some people will use this during light exercise and they'll just like walk around wearing it or cycle wearing it. Some people will do this when intervals and they'll wear it when they're doing like sprints or intervals on a bike or on a treadmill. Some people incorporate this with breath holds as well and kind of go a step further. Personally, I don't really like these and I would never really use them for anyone. In all honesty, they're super uncomfortable. I've used them personally like quite a bit training for other sports, but they're just super uncomfortable and most people don't want to be hating their training. There is the small amount of people who love the feeling, but it really, really sucks. On top of that is if you're doing it, say, during an interval session, it's going to reduce your ability to actually perform in that interval session. I would much prefer if someone was doing high intensity interval training just to really focus on that, then rather worrying about the mask. It may be much more relevant for like higher intensity sports where you have to be working in a very high output, or maybe your oxygen is getting restricted or something like that. But again, for hikers and mountaineers, you know, not so much. The only time I would really recommend this is if there's someone who's like.

[27:57] Hey i'm aware that i get really really out of breath very quickly and what happens is not so much as just a physical thing but mentally i really struggle with this and i notice as soon as my breathing starts to increase i start like really getting anxious about it and therefore my breathing gets worse and worse worse because i'm thinking about it i'm stressing about it whatever may be so in that situation there could be the argument that using this as a tool to try and practice gentle, moderate movement with this and get mental exposure to that type of thing in a controllable way so we can teach the body and mind that this isn't too stressful. I could see that. Obviously, you have to be very delicate if someone's dealing with anxiety or something with this type of stuff. But for CO2 tolerance, I don't love it. Again, I know a lot of people argue this. I know a lot of people do it, but it's not something I'd ever recommend.

[28:49] So with that being said, I think I've probably said enough on this. I've been talking for half an hour on this topic. Just to summarize, carbon dioxide tolerance, chemo sensitivity.

[28:59] Interesting subject. I don't think specific training for this is particularly necessary for most hikers and mountaineers. Because realistically, if you are following a smart, progressive training plan, you're probably going to improve this either way. And if you do struggle with breathlessness or want to improve your performance, I would sort of say the first places you always want to look is making sure you aren't doing this smart, progressive training plan. That you are doing some good, solid, long, steady state exercise, slowly progressing over time. Hiking, cycling, running, progressing that, having a good plan, getting your hours in. On top of that, somewhere in your training, having some higher intensity sustained efforts. Two minutes, three minutes, four minutes, five minutes, six minutes, seven minutes, eight minutes at a time where you're getting the intensity up a bit higher, getting that breathing up and pushing that higher, where you're teaching the body to deal with that, to sustain with it and feel a bit more comfortable with that. And maybe even, not everyone has to do it, but some small amounts of very, very, very high intensity. Every once in a while, do some sprints. Check up the intensity for 20, 30 seconds on a stationary bike. Absolutely max out your heart rate and then have a decent rest and do it again. Do that a few times. That again is going to be challenging the breathing, getting us up really, really, really, really, really, really high. And the body's like, I don't really like this. So I will create adaptations to better deal with this.

[30:26] Nailing that, because that is going to give us the best benefits as a hiker and mountaineer in a huge spread of things, as well as probably improve our sensitivity and tolerance to carbon dioxide. On top of that is if you struggle with breathlessness, one of the most valuable things you can learn is learning how to manage your pace and intensity going up hills. Most people, when they're struggling with this, they have no idea how to manage their pace. They have two speeds. They have, I'm climbing a hill and I'm stopping.

[31:01] But actually learning how to climb at an intensity which doesn't get you out of breath and practicing that and developing that, that in itself, without doing any specific breathing training, but just pacing training is amazing. You can see some dramatic improvements. And also on top of that is just getting exposed to some discomfort. And this will happen in that higher intensity stuff, but essentially just exposing the body in your training, not to things you're just completely comfortable with, but getting a little bit uncomfortable and sustaining that. So mentally, the body doesn't freak out and then just end up getting a little bit tough. That in itself is kind of where I would say everyone should start. That in itself is going to give so many benefits in so many different ways. And that in itself is just so valuable. On top of that, you can kind of layer on some really, really simple practical ways. Practice that nose breathing. When we're doing our long steady state stuff, when we're hiking, walking, pack walking, practice that. When we're practicing our pacing, when we're going up hills on the trail or going out steps of stairs on the trail, practice that nose breathing because that can help with that pacing. Really useful. Try that breathe light exercise. Practice it when you're walking, when you're pack walking on flat sections of the trail, when you're lying in bed, that can all be useful.

[32:13] And then if you did want to take this a step further and you're like, okay, cool, I'm doing all this stuff, but I kind of want to improve my breathing. I would sort of argue, as opposed to going down the route of breath holds or elevation masks, but going into specific respiratory muscle training, where essentially you're getting a particular device to train the inspiratory breathing muscles. It's essentially strength training for your breathing. And I've talked about this podcast previously, and I've done episodes on it. I am going to do another episode soon, diving into a bit more detail, but that's a method of training, which has huge potential benefit for hikers and mountaineers.

[32:50] But it doesn't really get talked about a huge amount. It doesn't really get plied amount. And I would sort of say there's much more evidence to that than some of these other things.

[32:57] And if you did want to use breath holds or elevation masks, then just use them as an addition. Just make sure they are the cherry on top of your training, which is the sundae. Don't use them to replace other training. Don't let these types of things impact your other training, meaning impact your desire, enjoyment, energy, recovery, whatever it may be. Use them as an addition in the truest sense of the word.

[33:20] So there we go. That's enough for me today. Giving a little bit of context to the whole concept of carbon dioxide and carbon dioxide tolerance and all of that. People who love this type of stuff, you may disagree with what I've said today. I really have tried to give context and be nuanced on all of this, but I know a lot of people are pretty gung-ho on it. If anyone's curious about this and just had follow-up questions, feel free to reach out any time. I hope that does make sense. And hopefully this will just kind of give a little bit more nuance and context to this discussion, which is a little bit one-sided when we look online. So with that being said, I'm going to wrap things up here. If anyone's interested in all of this and want to learn a little bit more or have follow-up questions, come join our community group. I'll leave a link for that in the show notes below. Free group talking about training for hiking, lots of people all around the world in there doing some really cool things. So if you're interested in learning a little bit more stuff, I'll pop a link for that in there. But aside from that, I hope you've enjoyed today. We'll talk to you soon. Bye.