Summary

In this episode of the Athletes Compass podcast, hosts Paul Warloski, Marjaana Rakai, and Dr. Paul Laursen address a listener question about the benefits of heat and altitude training for race preparation. They discuss how heat acclimation can improve cardiovascular function and lower heart rate during exercise, similar to altitude training. The hosts explore whether heat training can substitute for altitude training and offer practical advice on how to incorporate heat acclimation and respiratory muscle training into a routine. Nutritional strategies, including the potential benefits of ketone supplements, are also covered to help athletes prepare for high-altitude races.

Key Episode Takeaways

• Heat Acclimation Benefits: Increases plasma volume, lowers core temperature, and reduces heart rate for given exercise intensity.
• Crossover Benefits: Heat training can offer some of the same adaptations as altitude training, such as increased blood volume.
• Practical Heat Training Tips: Use saunas, hot tubs, or exercise in hot environments to induce sweat and physiological changes.
• Nutritional Strategies: Ketone supplementation and keto diets may enhance performance at altitude by improving energy efficiency.
• Respiratory Muscle Training: Using devices like the Breathe Way Better bag can strengthen respiratory muscles and improve performance at altitude.
• Individual Responses: Both heat and altitude adaptations vary greatly between individuals; personal experimentation is essential.
• Training Advice: Athletes should try to get some high-altitude exposure before a race if possible, but heat training can be an effective alternative if not.

• Exercise & Sports: The Breath Factor | Steve Neal
• Paul Warloski - Endurance, Strength Training, Yoga
• Marjaana Rakai - Tired Mom Runs - Where fitness meets motherhood.

Hello and welcome to the Athletes Compass podcast where we navigate training, fitness and health for everyday athletes. Today we are tackling an intriguing listener question about the benefits of heat and altitude training.

We have a listener question from Robert from Tucson, Arizona. He's training for a race at 7 ,000 feet, which is just over 2 ,100 meters for us who don't operate in feet. While he's living at 3 ,000 feet or around 900 meters and utilizing some training sessions at hot temperatures to stimulate physiological changes to prepare him for the race day.

Race day is about eight weeks away less now that because we got this question about a week ago. So Paul, let's review some of the heat acclimation benefits we've discussed in the past episodes.

Okay, yes, heat acclimation benefits. So you know all about these MJ, because I'm reading some of your comments on on Athletica and you're talking about getting hot these days, right? And yeah, so you're doing these, you're out there, you're training in the heat of Texas. It's hot, it's humid. Very key Key first thing is you get hot. And that's the main stimulus that has to happen. When you get hot,

Yes.

your body has to counter that hotness with something, right? It's got to get rid of that heat. So you're holding onto heat and you got to get rid of it. And one of the ways it does that is by shedding blood and sweat to the periphery. So blood flow goes to the periphery, to the skin, and sweat also goes to the periphery.

So ultimately you can kind of see what happens is that we're requiring more water on our system, right? And when you require more water, it leeches that from all over the body. And acutely you get this reduction in the amount of water that's in your bloodstream. That's called your plasma. So your plasma volume goes down acutely. And the kickback is that...

Sorry, you hemo concentrate, but the kickback is that you hemo dilute. So you're all of a sudden there's more water now, increase in plasma volume that happens in your bloodstream. And that makes exercise feel easier the next time you sweat more, more blood goes to the periphery and you have a larger stroke volume. You have more blood in your overall cardiovascular compartment.

Your core temperature is now lower after heat acclimating, got a bigger sweat rate, and your skin temperature will be cooler as well. So all these things wind up making exercising the heat feel easier. So I think that was the first question. Is that right?

That's right. And so I've noticed that my heart rate is lower. I almost... Yeah. Yeah.

yes, that was a big one. So I said your stroke volume was higher, but of course your heart rate is lower for a given exercise intensity. That's an important one. So thanks, MJ.

Yeah, so when you're running along, we don't know anything about stroke volume per se, but we noticed that, my heart rate is a little bit lower than it used to be. And I think I mentioned a couple of weeks ago, last week on Athletica after one of these sessions, I'm like, my heart rate is really low. Am I overtraining or what's happening? But it didn't even occur to me that my heat adaptation is actually working.

Mm -hmm.

As it should. So at any given, at the, you know, zone two workouts, we're like, my heart rate is super low. And typically coming from overtraining, like I'm like, am I, am I overreaching here? But it's, I think it's the heat acclimation that is working.

Yeah.

Sure. Yeah, remember that it can be either, right? So yeah, this is where a little bit of heart rate variability monitoring can help us getting in touch with your feel, knowing more of the context of how hard you're training this stuff. But absolutely, that is one of the, yeah, the key things is that your heart rate is lower for a given exercise intensity. So that's a biggie and we can all monitor that. Yeah.

Mm -hmm.

So the question our listener had was, are there crossover benefits from heat training or acclimation compared to hypoxia training with altitude training? Can you do one with the other?

Yes, this is a great little question, an interesting thought experiment. So a couple things, just first of all, we just mentioned first of all that in an acute heat situation, you might know from your sports science, we sometimes talk about training load and you can see your training load in Athletica, right? You've got like a load number.

Now that's usually measured as an external training load. And that's measured from your power or your pace, right, relative to your threshold. And what you get in either an altitude or a heat exposure is you get a higher internal training load. So your heart rate is higher for a given external workload, pace or power.

And in either hot conditions or in altitude conditions where the partial pressure of oxygen is lower, right? And where, you know, you're having to, you're having, there's less oxygen per breath ultimately. So the heart has to beat faster to move that blood around a little bit quicker. Either way, you've got that internal to external ratio is kind of curved. So there's the similarities between your.

between your altitude and your heat. Now to the question is, if I've got a race at altitude, but I can't get to altitude, could I use heat as a bit of a tool to prepare myself for altitude? And the answer winds up being yes. The reason is with that, we went through the different adaptations that happen with the heat. You've got that

HEMODILUTION, all right? Remember we learned that we've got that increase in plasma volume. That's the fundamental thing. So your kidney is all of a sudden retaining all this sodium and more water floods into the cardiovascular kind of compartment. And it winds up tricking the body to say, we're HEMODILUTE here. We're actually in the hot condition. It's looking to the body.

like we don't have many red blood cells present because there's more water relative to the red blood cell mass. So what does the body do? The kidneys do, they secrete more erythropoietin and you might've heard of EPO, erythropoietin. So you get actually a kickback and you get your bone marrow, it starts to react to that EPO and produce more red blood cells. So you get a combination, you get more red blood cells.

you

an increase in hemoglobin mass, and you still get that increased plasma volume too. So your overall blood volume expands even just, and I'm just talking in the heat condition. And that's a very similar adaptation that you also get in the altitude, the hypoxic exposure too. So the answer simply is yes.

you

Is it as effective as specifically going to altitude? Probably no, right? And there's some nuances here. But in terms of bridging the gap, because if we've got a race at altitude, 2 ,000 meters, that's going to be tough, right? If anyone's done that before, going from sea level up to 2 ,000, that's solid. I will do that here in Revelstoke. Top of Mount Revelstoke is actually

Thank you.

1900 meters. So I totally know what that feels like. I'll go from, I'm here at 500 meters right now at my house. And that's, I love that. It's one of my favorite rides. I'll go up to 2000, you know, close to 2000. And yeah, you start to feel it at the end. And if I've got a race up there without any prior exposure, that's tough on the body. So it's good to have either types of preparation, either, you know, some sort of a heat acclimation.

or ideally some time at that altitude to prepare for it. Because there's, yeah, we can talk more about some of the adaptations and challenges with just with altitude.

We're all about giving advice for everyday athletes. So can we talk about like what kind of, how much of heat acclimation would Robert want to do and for how long?

Yeah, I think it would be anything he can get his hands on in the practical sort of situations. Like, what could I do to get hot in my workout to get some of those adaptations? And you're an expert at this one, MJ, where you've got lots of different things you've done in the past, things like going into a sauna potentially.

after your workout or into a hot tub after your workout or training in the heat of the day, which I know you're doing right now over in Texas to prepare for Worlds. Any way you can get hot in your exercise to induce more sweat is probably going to be a good thing. What do you think?

Yeah, I, I've noticed that when I do it like several times a week, I've started to feel the acclimation before I would do maybe occasional heat run, but I didn't like notice any, you know, remarkable, adaptation to the heat. And even though like I am sitting and watching baseball in the heat, the passive

It just doesn't hit me the same way as running an hour in the heat. It's a totally different effect in my opinion. So yeah, I'm running about 60 minutes. I did 90 minutes the other day. That was maybe a little too much. It takes a lot out of me. But I can start to see that I'm getting...

Thank you.

Thank you.

better at it. I can't say that I really enjoy it too much yet, but I'm getting better at it.

That's good. So what you're saying is the pass of sitting there watching the baseball games isn't really as effective as actually getting out there and training in the heat. The two are totally, in your opinion, they're totally different.

Thank you.

Mm -hmm.

Totally different, yeah.

There you go. Okay, so that's that's pretty key. You got to get moving in there. I'm reflecting on Cindy Maloney, who's a you know, a longtime Athletica user and Ironman Kona Champion in my view She's prepared for it with a lot of passive training actually in the heat Sorry in in the cold of Revelstoke here, and then she would go into like the sauna

Thank you.

Thank you.

after she did some of her training sessions, whether it be a swim session straight into the sauna after that. I know there's another Athletica user, Brett McFedrin, who heads in after, sometimes he'll just be out for a long run and knowing he's gonna go travel someplace, he'll come straight into the sauna at the pool and I'll see him in there and ask him when he's up to see how he's doing. I said, ⁓ did you swim? No, I just went for a run and I'm here now. So it's like.

These are little tricks and stuff that you can do. So you can prolong the warmth that you get and then by sitting passively in a sauna thereafter. But I think in those contexts, they've got the activity in them first. Whereas sitting at the baseball game, you probably haven't trained beforehand. True? So maybe, Marjaana in your, I don't know if the context would ever work, but if you could ever potentially get to that baseball game, train, then sit at the baseball game in the heat. That might be the best.

Thank you.

Yeah.

Thank you.

You

you

Yay! That sounds lovely. Is there, for Robert, he's already not really high up, living, you know, like around 900 meters. Is there a possibility that he's like partially acclimatized to altitude? Compared to Steven. Yeah.

Yeah, 900's not bad. Is it 900 meters or feet that he's at?

900 meters, sorry, was 3000.

Yeah, 900 meters isn't bad. It'd definitely be partially acclimated at 900 meters for sure. It's not a bad training altitude actually. It's kind of in the, like 1500 tends to be around the threshold for like doing some sort of a, some place where you'd get the classic altitude adaptations, which you just go over basically is, you know, you do get that.

you know, a reduction in the amount of oxygen, a partial pressure of oxygen that you're breathing in. So your, your saturation of oxygen in your bloodstream, you might see, I've seen those in the hospital where you actually wear like a, an oximeter on your finger, or these are even now in our, you know, in our watches, we can actually see a lot of these, these, the saturation is actually sitting there. So that saturation of, of oxygen to hemoglobin is lowered.

And you'll see there's a counter. There's a couple different things that the body tends to do to counter that. One is to breathe a little bit faster. And then the other one is to induce, is to release EPO, as we mentioned, erythropoietin, where there's a kickback and a production of red blood cells to counter that as well. So hemo -concentration from the more red blood cells to counter that.

to the altitude, because that's where it gets really hard. You can kind of hang out at L1, L2 doing it at altitude, but it's where you're really breathing hard that it gets altitude. You really sort of feel it. And yeah, if you can kind of get used to that hyperventilation, you know you're going to have to breathe a lot harder. Yeah, if you can do that beforehand, that's the earlier the better kind of thing.

So he's, he's set up pretty well already partially acclimatized to the altitude. And then if he keeps doing like a few weeks of heat adaptation training, he should be ready to go racing in a few weeks.

Totally, yeah. And there's other things he can do too, right? Like we've talked on the training science podcast, we had Steve Neal, who's an expert in the respiratory function and respiratory muscle training. And one of the ones that I love is the Breathe Way Better bag from Isocapnic. And basically you're putting like a, you've got basically a metronome. There's Paul's got one, fantastic.

you

You know, you can basically just, you know, you enhance your breathing muscles ultimately to, you know, kind of counter that, the challenges that your respiratory apparatus are going to experience for high intensity exercise at altitude. So that's another great one to do. Paula, you've got experience with Breathe Way Better. Tell me what you've learned with it.

Yeah, the only thing that I've used it for about a year and it helps me breathe more into my belly as opposed to just chest breathing. And it helps me more with the kind of using the full capacity of my lungs. And I haven't noticed necessarily a training benefit.

but I'm not sure I would notice it. I'm not sure that there's, I'm going to be sensitive enough. I have asthma and I do know that the asthma has been less. So maybe there's a correlation there, but I do like using it.

Yeah, what winds up happening sometimes is there's this at high intensity exercise and especially under altitude sort of situations, you get this, there's this reflex. It's got a fancy name called the Metabo reflex. And it basically, there's something that's going on, you know, in the, you know, in your brain that is, and through these different afferents, nerves, receptors that are down here that are kind of curbing.

your fatigue response. And ultimately it's linked to the respiration. And if your respiratory muscles are fatiguing, they actually go and inhibit the whole system. They go back and inhibit the muscular system. So what we think probably is going on when you do work with Breathe Way Better's or an associated respiratory muscle training apparatus is you're improving the muscular endurance and the...

Also the muscular strength of the respiratory muscles. Think of your respiratory muscles, diaphragm, intercostals, as just like a separate kind of person or a separate muscular kind of group. And when those are strong and not fatiguing, they allow an enhanced ventilation of your lungs, right? So that there's no

Because imagine if you're all of a sudden, you're not able to ventilate your lungs. Well, that's that's like the key one of the key things that's that's inhibiting our ability to saturate the blood with oxygen so you want to you can and this is kind of a bit of training that you can do just like key declamation is The respiratory muscle training is something that you can also do Just while you're watching TV or or listening to a podcast, right? Like it's just whatever it's

It's not that taxing of a thing to kind of go and do, but you're isolating the respiratory muscles and you're specifically working on that aspect that you know is going to come, right? Like you know that there's going to be a pinch point in this altitude race where you can actually prepare for it specifically with a respiratory training device. And of course also heat.

So there are counters we can do when we know we have some of these other environmental challenges in a race ahead of us.

Well, that brings me to a question about altitude acclimation and racing. I have a, one of my athletes from the Midwest, from Madison is racing in Leadville, which is obviously at altitude. There's theories about going up the day before and leaving at that. There's theories about several weeks prior. I mean, that's not really feasible for him. What would you recommend him doing at this stage?

you know, to, to prepare for that kind of a race.

Yeah, I think it's probably similar stuff. You know, our audience are everyday athletes, right? When I was working with the New Zealand Olympic program and we were, well, we use altitude all the time. We'd use it for just, even if there wasn't an event at altitude, we'd be using it to prepare for events at sea level.

magic ways that people kind of prepare. But when we're talking to everyday athletes, you do what you kind of have to do. You do what you can. In general, if it was an A event and you had some resource and you could afford to go there early and make a holiday out of it with the family, you'd go there a little bit earlier for sure. And that would be, and you'd be able to kind of train, just like when many people train in...

you

for Kona, they go to Kona 10 days or so beforehand and they get their heat acclimation that way. Same sort of thing with an altitude event like this. If you can go a little bit earlier and start to get used to that and do a couple of high intensity sessions in that altitude so you know what you're dealing with, then perfect, that's great. But the reality is it's the pocketbook and your logistics and your work environment is probably gonna dominate the decisions here. So therefore you're gonna probably do what you can.

arrive whenever, but do some of these, if you can, do some of these cheaper alternatives like the heat and like the respiratory muscle training aspects to get the benefits to prepare you appropriately for your event. So I don't know if I answered your question well there or not, Paul, but it was a roundabout way of saying that's what I would do.

No, I mean, what you're talking about is if it's feasible, you know, that he can go up to altitude early, but if it's not, then we have a couple of alternatives here that we've been talking about with the heat acclimation and the respiratory training that might give him some similar benefits.

Yep. Yeah, you got it.

What about nutritional, like iron intake as we're doing heat acclimation or altitude? Is there any like increased requirement as we're...

I'm so glad you asked that question. I don't even know if it was on the run sheet, but there is a huge nutritional component that very few people are aware of. And it actually relates to ketones. And we've talked before about ketones, ketone supplementations, all these sorts of things. It turns out that's actually why ketone supplements were invented originally. They were invented by

a DARPA initiative. DARPA is like the military grade research arm in the United States. They, along with Kieran Clark of Oxford, invented the ketone supplements. Delta G is one. There's a few that own the patent to be able to give these. It was invented specifically for extreme environments, including altitude, including underwater.

territory, what do you call it? Environments where, you know, and probably heat as well, but the ketones are energetic compounds, substrates, like your carbohydrate, like your glucose, like your fatty acids, but they're more energetic and you get more ATP, the energy molecule per unit of substrate. And you wind up thinking clearer.

in these extreme environments, you get less altitude sickness, which is a common ailment that happens when we go to altitude. And it's just because the whole system runs better. So that is actually another thing that I know personally works is when I become keto adapted before I go to an altitude event. Peter Tia did a fantastic blog about this when, you know, it was in the earlier days, but I'm sure it's still on his record.

And when he was first experimenting with ketogenic diets, when he was a cyclist, he noticed when he went to an altitude training camp, just how good he felt and how he really, he hardly had to kind of supplement anymore. And I noticed the same sort of thing when I could just, you know, it just, I wasn't fazed. And same with other athletes that I've dealt with as well. When they go to these altitude,

locations and they are more keto adapted than not, they tend to be really good at altitude. It just goes with fitness too, right? When you are a fitter athlete, you're more fat adapted and you just have more resources available for dealing with any sort of environmental insult, whether it be heat or altitude. So yeah, nutritional, there's lots of different, any ways you can

curb your nutrition in a healthy way to have your liver cranking out more ketones. If you're unfamiliar with what ketones are, have a listen to our podcast that we did on ketones and keto adaptation.

So again, practical advice. How would a pulse athlete use ketones when he goes to the race?

Yeah, and that's a tough one, right? Like, you know, I'm not going to throw out advice because it's not my athlete. And these sorts of things you want to pilot beforehand. And you know, you want to be, you know, keto adaptation, honestly, it can take up to, you know, a year for certain people, right? In terms of getting there. It takes some individuals, they can get there within a month, no problem.

Mm -hmm.

but others takes a lot longer. So it's, there's that individual effect. And then the, the supplements too are very individual also, right? And so you would almost want to run, you know, a, a pilot project yourself and never want to do this. Don't make the same mistake I did with one of my athletes where we, we used ketone supplements in a important race and it absolutely ruined him. So,

There's very much an individual response. There's a dose response. But it's one thing that you could kind of tinker with. It's just with knowledge the fact that there is a mechanism by which these might be assisting your performance in an extreme environment. But yeah, just...

Mm -hmm.

These are long term projects, so I can't really make a recommendation if I'm honest and truthful.

So if he has time.

Yeah. Yeah. So if he's got time, he could have a little side project to figure out if key tones work for him.

I'm sorry.

Yeah, absolutely. But it was me, like I'm so, you know, very experienced with going through these phases of, you know, of being keto adapted as you are MJ. So it's like, yeah, I would, I would say, okay, now we're going to get, we're going to get really fat adapted for this because of XYZ, right? And do some key, key sessions up there, but yeah.

Mm -hmm. Mm -hmm.

So one of the things that I'm hearing is that altitude training and preparing to race at altitude are two different elements of training. Is that accurate? I mean, there are commonalities, but they're different.

Preparing, yeah, preparation versus the acute. Yeah, yeah, absolutely. Yeah, so, yeah, the preparation is, yeah, it's all, it's, exactly, like it's, well, it can be, right? Like you could go there to have your preparation, because principal specificity is ideal, but.

Mm -hmm.

Great.

Again, we were referring to the everyday athlete, probably doesn't have that luxury. And then we've got to do these other preparatory things to try to counter those. But yeah, on the day, yeah, well, we could talk about that. What about execution, right? On that actual day, you've got to be recognizing that your internal training load,

is gonna be higher, like your internal and external training load is gonna be a lot higher. So you're, again, hopefully you've prepared as best you can, but if you're at altitude, you've got a reduction in partial pressure of oxygen, heart rate's gonna be higher relative to the moving speed or power output. That's just the reality of it. So pace accordingly, right? This is why ketones work. There's a...

One of the things that also happens at altitude is there's an increase in carbohydrate requirement, actually. So you'd think, well, you're going to need to counter that with more carbohydrates. You could, but that's actually why ketones work too, because they blunt that need a little bit. You wind up becoming less or more equivalent in terms of your carbohydrate needs.

Yeah, you wind up because ketones are being produced. Yeah, you're not, the carb sources aren't being drawn as much out of you and you're more used to these being, you know, the mind, the brain is getting more of the energy that it kind of requires. So yeah. So yeah, I'm not sure, Paul. We're kind of all over those. These are really, these are challenging.

They are.

you know, the challenging kind of situations to optimize for, which is why they're so interesting from a an execution standpoint. You know, and you know, we like I've got the Dean current, current, as he's a book over here on the ultra marathon man and you know, like listening to you know, I think he's gone to Leadville and there's there's there's some crazy stuff that

that he's done up there as well. And yeah, it's just, yeah, it's not an easy task when we're at altitude. I think there's heat up there too, right? I think they have actually, Leadville's both heat and altitude. So it's a super extreme kind of race.

Mm -hmm.

And I think there's a lot of individual responses to altitudes adaptations as well.

Yeah, I mean, it's, yeah, you've got to be so fit and so strong for that, right? And all you've, you've, you've really have to tick all the different boxes from your, you've got to be an incredibly fit individual. You've got to have the strength endurance. You've got to have, you've got to be metabolically flexible. You still, you still need calories throughout the whole race too, right? So you've got to have your nutrition dialed.

and mentally you've got to be absolutely all over prepared for what that race is going to entail. So yeah, anyone, I just take my hat off to anyone doing those events. Super, super challenging. And yeah, you'll discover yourself out there, that's for sure.

Totally.

Yeah, the self -talk. I want to know. But yeah, what an adventure. Good on you.

you

Yeah, I'm working.

Totally. Yeah. Good luck. Good luck, Rob. Absolutely.

So let's look at what are the takeaways from this episode. So we rehashed and re -talked about some of the things we've talked about with the heat acclimation is that you become acclimated to the heat through repeated exposure and your heat and your heart and your blood change to meet the needs of the training. There are...

some commonalities between the adaptations of heat and altitude training, including increased blood volume and cardiac function. So there is some crossover in terms of if you can't get to altitude, you can do some heat training and you get some of that benefit. But there are some things that only come from altitude training, but heat training can sometimes help

that process, but it's all very individual. And the third thing is the nutritional component that we, there may be some benefit to the ketone supplementation. And I say maybe because that's something that you need to experiment with to see if it works for you. A ketone based or a keto diet may prepare you better for the event.

but it's something that you need to prepare for and be ready for and don't try anything the day before the race. That is the key. So Rob and for my athlete, John, you know, there's some work that we have to do to get you ready for your event. But that's all for this week. Thank you for listening and join us next week for the Athletes Compass podcast.

You can help us by asking your training questions in the comments and our social media, liking and sharing the podcast and giving us five star reviews. For Marjaana Rakai and Dr. Paul Laursen I am Paul Warloski and this has been the Athletes Compass podcast. Thank you for listening.