#PTonICE Daily Show – Friday, July 14th, 2023 – It’s a deep burn: heat-based recovery

In today’s episode of the PT on ICE Daily Show, Fitness Athlete division leader Alan Fredendall defines heat-based recovery including hot tubs, whirlpools, and saunas. Take a listen to learn how to discuss cold plunging with your patients or athletes.

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00:00 INTRO
What’s up everybody? Before we get rolling, I’d love to share a bit about Jane, the practice management software that we love and use here at ICE who are also our show sponsor. Jane knows that collecting new patient info, their consent and signatures can be a time consuming process, but with their automated forms, it does not have to be. With Jane, you can assign intake forms to specific treatments or practitioners, and Jane takes care of sending the correct form out to your patients. Save even more time by requesting a credit card on file through your intake forms with the help of Jane Payments, their integrated PCI compliant payment solution. Conveniently, Jane will actually prompt your patients to fill out their intake form 24 hours before their appointment if they have not done so already. If you’re looking to streamline your intake form collection, head over to jane.app slash physical therapy, book a one-on-one demo with a member of the Jane team. They’ll be able to show you the features I just mentioned and answer any other questions you may have. Don’t forget, if you do sign up, use the code ICEPT1MO for a one month grace period applied to your new account. Thanks everybody. Enjoy the show.

All right. Good morning, team. Welcome to the PT on ICE Daily Show. Happy Friday morning. Hope your Friday’s off to a great start live here on YouTube and Instagram, everywhere you get your podcasts. My name is Alan. I’m happy to be your host today. Currently have the pleasure of serving as the chief operating officer here at ICE and a lead faculty in our fitness athlete division here on Fitness Athlete Friday. We consider it the best start day of the week. We talk all things CrossFit, Power Lifting, Olympic Weightlifting, endurance athletes, running, swimming, cycling, all that sort of thing. So if you’re interested in working with the recreationally active patient or client, Fridays are for you. We’re going to talk all things heat based recovery today. We spent two weeks ago talking about cold based recovery. So it’ll be a nice change of pace on the opposite side of the spectrum. Before we get started today, first of all, I want to say big thanks to our friends at FIRE, Foraging Youth Resilience for having Jeff, our CEO, and myself out this week to their annual camp outside of Boulder, Colorado. Huge fun getting to know a lot of the kids, the campers, as well as a great network of coaches, games athletes, all sorts of wonderful people from the CrossFit space coming together to help support FIRE. It was great to meet everybody out there. If you want to learn more about FIRE, you can read more on their website. We’re big supporters of FIRE here at ICE. So you’ll continue to see us have more opportunities to help get involved with FIRE and support FIRE as time goes on. Some courses coming your way from us in the fitness athlete division. If you’re looking to catch us out on the road for clinical management in the fitness athlete live, that’s our two day live seminar. Your next chance will be September 9th and 10th. That’s going to be out in Bismarck, North Dakota with Mitch Babcock. And then you can catch the same month at the end of September, September 30th and October 1st out on the west coast. Zach Long, aka The Barbell Physio, will be out in Newark, California. That’s in the Bay Area of California. And then online, our clinical management fitness athlete essential foundations, our eight week online entry level course into the clinical management fitness athlete curriculum. That will start September 11th. That’s taught by myself, Mitch Babcock, Kelly Benfee and Guillermo Contreras. And then the next week after our level two online course, clinical management fitness athlete advanced concepts start September 17th. So you can learn all about that at ptenice.com. That’s where everything lives that you want to know about ice. So today’s topic, heat based recovery. We have talked about cold based recovery, specifically two weeks ago here on fitness athlete Friday. We talked everything regarding cold plunges and cold based recovery. We’re going to go to the opposite side of the spectrum now and talk about heat based recovery. So the big summary from if you didn’t catch us two weeks ago, the big summary from cold plunging is that we really want to avoid it after exercise. It seems to really have an effect on that post exercise inflammation effect that we want to build strength, build hypertrophy. It does have some benefits, but we mainly want to avoid it after exercise. You’re going to see a recurring theme here with heat based recovery. But I do want to start by first of all, defining what is heat based recovery, talking about the differences between things like hot tub or whirlpool. Differences between you may have questions about infrared versus traditional sauna. And then I want to talk about some of the research supporting the use of heat based recovery, but also the application of it both in the clinic. And when you’re discussing these topics in the clinic or the gym with your patients or athletes. So let’s start first by defining it. What is heat based recovery? We have a couple different types. The first is what we’ll call hot water immersion. This is basically the opposite of cold water immersion or cold plunging. This is where you get in a hot tub or a hot bath or a whirlpool machine, some sort of hot water immersion. Now defining temperatures here is really important. We did that two weeks ago with cold water immersion. Really important to note that at least from the research, we have specific temperature ranges that we’re discussing with all of these modalities. And we’re also assuming that you have your whole body immersed in something like a sauna. Or that if you’re in hot water, for example, a hot tub or a hot bath, you’re immersed at least up to the level of your neck. A lot of what we’re going to talk about doesn’t apply to you if you’re somebody that just sticks your your foot in the hot tub. Or doesn’t otherwise get fully immersed in whatever modality you’re using. So two different types of hot water immersion, hot tub or hot bath. When we’re at home and we run a bath, when we look at what is the temperature of what the average human being might consider quote-unquote hot. A hot bath is right around 100 degrees Fahrenheit. And that your average hot tub is not too different. A hot tub that you might get into is going to be somewhere between 100 to 110 degrees Fahrenheit. But now when we look at this from a research perspective, it’s usually tightly controlled and it’s usually tightly controlled a little bit hotter. So when they look at hot tub whirlpool type immersion in the research, they’re looking specifically at a temperature range of about 110 to about 120 degrees Fahrenheit. So if you’re somebody that really hates a hot bath, if you run a hot bath and you wait for it to cool down a lot, then just know this is going to be on the upper end of your temperature comfort. Why this matters is that when we add that that circulating bubble component to a whirlpool, to a hot tub, it seems with the water continuously moving that it makes that hot water immersion just a little bit more tolerable and therefore they bump the temperature up a little bit. Again, 110 to 120 degrees Fahrenheit. And again, immersion in a hot tub whirlpool up to the level of the neck. Now duration is really important. We talked about that with cold plunging. That if you’re somebody that gets in for a minute, you probably don’t have to worry about the positive or the negative effects because you’re really not doing it. The same is true here. When we look at hot water immersion, when we talked two weeks ago, we talked about humans have a really great tolerance for heat at rest. We can sit outside 70, 80, 90, maybe even 100 degrees, especially if we’re in some shade and we can be okay. We don’t have a great tolerance for cold at rest. And we see this carry over into hot water immersion that because we’re so much more tolerant to heat, we see duration for hot water immersion a lot higher. We often see duration 15 to 30 minutes in a whirlpool in a hot tub. Maybe you’ve been at a hotel or a resort or something. You’ve seen that sign. We’ve all seen that sign on the hot tub. You know, don’t stay in here too long. Max time 20 minutes, 30 minutes. That tends to be our tolerance for hot water immersion. So somewhere between 15 to 30 minutes, but definitely longer than what we’re used to seeing with cold water exposure where the general recommendation usually never exceeds 10 minutes. Now getting into sauna, temperatures are going to go up. We’re no longer actually sitting in water. We’re usually sitting in a room that is either steam heated or dry heated. Those also have different temperature parameters when we look specifically at how they’re studied in the research. Traditional sauna, whether it’s dry or a steam sauna, is a lot hotter. 150 to up to 220 degrees Fahrenheit. Infrared sauna is going to be lower, 120 to 140 degrees Fahrenheit. And again, the duration for sauna is going to be higher, a lot like hot water immersion. Somewhere between 30, maybe even to a 90 minute dose, and that’s going to be mostly for infrared sauna. That would be really tough to do in a traditional sauna. So that’s how we define hot water immersion and also what we would call just sauna, sauna protocol, traditional or infrared. Now the research. I want to share a couple of different papers with you as we get into talking about what does the research support? What does it not support? Talking back to hot water immersion. So again, our hot tub or our whirlpool protocols. A great paper from 2022, the Journal of Sports Science. More and more Gamino and colleagues, pardon me butchering that, looking at hot water immersion. They took folks and they had them sit in a whirlpool for 15 minutes at 110 degrees Fahrenheit. They also had another group sit in a cold plunge at 50 degrees Fahrenheit and they compared outcomes on the quadriceps muscle. They wanted to look at specifically the contractile properties of the muscle itself and found that the group sitting in the hot water after exercise had increased contract properties of the quadricep muscle compared to the folks who did cold water immersion and compared to the folks who did nothing, who sat at a room temperature room. So the the effects of hot water immersion appear to have a more beneficial effect on our muscle and we’ll get more into that as we get more into the research. My next paper, really old. I love some of these old papers that just show how long we’ve been studying this stuff. Francisco and colleagues back from 1985, so before I was even alive, Journal of Applied Physiology. Looking at the use of hot water immersion and comparing it to basically an active recovery protocol. So two groups of subjects, one group exercising at 60% of their VO2 max. So essentially an active recovery spin on a cycle or a really really really low slow jog, something like that. To a group that did an hour in a whirlpool at 105 to 110 degrees Fahrenheit. And then they did a crossover here. So they took both groups and then flipped them a couple of days later and had them repeat the same thing. What they found in the group who sat in the hot tub for 60 minutes is they had an almost identical cardiovascular change. So they had an increase in their cardiovascular output and their mean arterial pressure, which just kind of tells us that there is a cardiovascular demand on the body when you are exposed to heat that mimics low-level active aerobic recovery type exercise. So what does that tell us? That tells us that first of all if we are looking for a recovery day that a longer hot water immersion or maybe a sauna can be a viable option in place of a recovery workout that we’re going to get some increased cardiac output. Our heart rate is going to elevate. We know being exposed to heat we’re definitely going to sweat. That’s going to come on board no matter what. But we’re going to see blood pressure changes as well. That tells us we’re kind of getting a flushing pumping effect when we’re exposed to heat specifically in this study hot water immersion compared to if we went to the gym and just spun on our bike or went for maybe a really long walk or a really slow jog or just some sort of active recovery exercise that they appear about equal. Which is great if that’s what we want. If we’re trying to limit cardiovascular load, if we’re trying to limit volume on our body then we need to be mindful that a longer duration hot water experience can have that effect on us. So it appears to be about an equal effect, which is nice. The next study here, Borg and colleagues from 2020, the International Journal of Sports Physiology and Performance, looked at hot water immersion versus cold water immersion versus control. Specifically they had these folks do these modalities after cycling in what they called hot weather, 75 degrees Fahrenheit. So they went for a long bike ride in the heat and they came back. They threw one group in cold water immersion in the cold plunge. They threw one group in hot water immersion, a whirlpool, and one group just sat at room temperature. And they found that those exposed to the hot water immersion were more likely to report that the session they had just performed, the cycling session in the heat, was easier. And they also had a lower cardiovascular response to those who had a cold water immersion. So it seems like when we’re cooling down we want to choose heat as it’s easier on our body, easier on a cardiovascular system than finishing a hot workout in the heat. It sounds great. We’ve all had those workouts. I just had one two weeks ago where we literally want to stick our head in the sink, which is exactly what I just did, and just cool down our head. That seems like what we want to do, but we know that can have sort of a shocking effect on the body compared to if we ease ourselves out of the heat with maybe not exactly what we just did in the heat, but we choose something that’s going to feel temperature neutral compared to what we just did, which was a really tough workout in the heat. Heat exposure after exercise, especially in the heat, seems to have a beneficial effect as we’re trying to cool back down to baseline. Now switching gears and looking at the sauna research. So this is just as popular as everybody wants to know about cold plunges. Everybody wants to know about sauna protocols. If you listen to anything about Andrew Huberman, you have been blasted with more information than maybe you’ve ever wanted to know about the sauna. But I want to pick just a couple papers here looking at sauna exposure, specifically after exercise. So Bezoglav and colleagues 2021 International Journal of Environmental Research and Public Health. This is a great study. This doesn’t actually research anything on sauna protocols itself. I love this study. This is basically a patient expectation, an athlete expectation of what athletes expect will help them recover and what they actually choose when they are performing their recovery. And it’s just really important to know this paper in the back of your head. That 97% of athletes surveyed use sauna as their number one choice for recovery. So that’s really important for us to know. We have to be able to speak intelligently about good, bad pros, cons about sauna with our athletes knowing that 97% of them are thinking I’m not feeling great. I’m feeling banged up. I am going to choose sauna as my number one recovery protocol. And we know this from physical therapy research. Massage is also popular. Not surprising. It’s popular with athletes. 87% of athletes choose massage as their secondary recovery protocol. And then 80% choose taking a nap, third. So in that order, sauna, massage, and napping. So that’s a really important paper to know. Miro and colleagues from 2015 in Springer Plus. This is an online open access journal. Looked at comparing folks doing infrared sauna, traditional sauna, after performing either hypertrophy focused resistance training for 60 minutes or endurance training. So they basically wanted to create a bunch of muscular damage and then have folks either get in an infrared sauna or traditional sauna. This study also had a crossover design. So the objective outcome here was a counter movement jump test and then also effects on the cardiovascular system. So that traditional sauna was performed at 122 degrees Fahrenheit for 30 minutes. The traditional sauna was performed at 70 degrees Fahrenheit for 30 minutes. And again, both groups exercise really hard for an hour. The traditional sauna group saw a reduction in performance on the counter movement jump after sauna protocol compared to the group using the infrared sauna. The traditional sauna group also had a significant spike in their heart rate. About 30 to 40 more beats per minute resting while sitting in the traditional sauna than the group sitting in the infrared sauna. So again, like we talked about a couple papers ago with environmental exposure, it seems like using sauna, specifically a really hot traditional sauna after exercise, seems to have a negative impact on our system. Of it’s just too much heat load, it’s too much cardiovascular load. It can lead to both negative performance outcomes, but also negative physiological outcomes. Supporting that, Skorsky and colleagues from 2019 International Journal of Sports Physiology and Performance. This group was looking specifically at performance. They had swimmers perform 4×50 meter sprints. I don’t know anything about swimming. I assume that’s a tough thing to do to do 4×50 sprints. Afterwards, the swimmers were either put in a group where they sat passively at room temperature. For 25 minutes or they did three eight minute rounds in the sauna, a traditional sauna at 185 degrees Fahrenheit. And then they had those athletes come in the next day and repeat the 4×50 swim performance. All of the subjects who used the traditional sauna after the sauna reported a stressful experience, both physically and mentally. And then the next day all of them had impaired performance when they went to repeat the 4×50 swims compared to the group that sat at control. They obviously did not report sitting at room temperature as a stressful experience. And they all performed better at the 4×50 than the sauna group. So it appears that longer duration, hotter traditional sauna seems to have a more negative impact on recovery. So what does this tell us? What does all this research tell us? How can we apply this with our patients, with our athletes, when they’re asking questions about sauna? Maybe they’re already using a sauna protocol. So as we talked about two weeks ago, cold water immersion, cold plunging appears to have a really negative impact on performance and recovery when used directly after exercise. Compared to hot water immersion, whirlpool, hot tub used after exercise. And it also really seems to affect our ability to adapt to the heat. So the takeaway here is that if we’re just finishing exercise, maybe traditional sauna, especially for a longer duration, especially for a higher heat duration, is maybe not the modality of choice. Just like a cold plunge is maybe not the modality of choice. Which is not to say we can’t use heat as recovery modality. But if we’re thinking we just finished training, we should look towards that hot tub. We should look towards that whirlpool. We should maybe look towards that active recovery. And we should save a really long, hot traditional sauna or a cold plunge for maybe before training earlier in the day. Or what we don’t have research on yet is what is that window? How much time difference between training and using a really hot sauna or using a cold plunge is still going to allow us to feel better recovery wise but not have those negative effects on performance. We don’t know that yet. But for now what we can recommend is stay away from that cold plunge. Stay away from that really hot, long duration traditional sauna about right after training. Give yourself a gap. Again, we don’t know how long. Or do it earlier in the day sometime before you actually start your exercise protocol. We do know that both hot water immersion and infrared sauna offer cardiovascular effects that are similar to active recovery. So if we really are not feeling like exercising today, if we’re really feeling like we need a day off, we can still have some positive health benefits from going and getting in the sauna. Especially something like an infrared sauna or sitting in a hot tub for maybe 10 to 30 minutes. But we really need to consider avoiding that long duration traditional sauna. It appears to have a big effect on our cardiovascular system. It’s adding a training load. It’s adding a heat load to our body that’s going to cause our body to need to adapt to that stress. So big term takeaways. There’s no shortcut, right? What we’re seeing in the research with both cold water immersion and hot water immersion, there’s no shortcut here. We need to allow the body’s natural inflammatory response to the exercise that we just did occur if we want to reap the benefits of that occurring. Yes, these things can help us feel less sore. Yes, they can help us feel less fatigued. But if we use them too much, they do seem to have a long-term detrimental effect on our performance. Which kind of defeats the purpose of going in and doing a hard workout, a long run, a long bike, a long CrossFit session, a long weightlifting session, whatever you’re doing. If we chronically use these things, yes, we might feel better. But we need to be concerned that maybe we’re leaving something on the table as far as strength, as far as hypertrophy when we use these kind of extreme temperature modalities, cold plunging, really really hot sauna. I could imagine that one study that showed a really detrimental effect was only 185 degrees. Some traditional sauna protocols in the 200s. I know Jeff Moore does the sauna at 205 degrees, I think for 15 minutes, which is even more of a heat load than 185 degrees. So just be aware of that and understand how to speak about these things with your patients and athletes because they’re going to have questions about it. Remember that paper? 97% of people look to sauna is the first choice for a recovery modality and then massage and then taking a nap. So 97% of people could use probably more education on sauna because we know they’re thinking about using it. So I hope this was helpful. We have an entire week in clinical management fitness athlete essential foundations dedicated to this now. We talk all things nutrition, sleep, we talk cold water immersion, hot water immersion. We also talk about compression therapy. So things like massage, massage guns, cupping, all that sort of thing. We discuss all of that research that your athletes, your patients want to know about when they come into the clinic and ask about recovering from exercise. So I hope you have a wonderful Friday. I hope you have a fantastic weekend. Thank you for joining us. Have a good day. Bye everybody.

22:33 OUTRO
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