Cold Plunge Myths: Short Exposure Does Not Mean Low Risk — Part 2

Natalie Hood continues her conversation with Dewey Case of the Council for the Model Aquatic Health Code, separating cold-plunge science from wellness-industry hype.

Cold plunges may be popular, but cold water changes chemical reaction rates, sanitizer performance, testing accuracy, and the body’s physiological response. Being young, athletic, or highly experienced around water does not make anyone immune to blood-sugar crashes, loss of consciousness, drowning, or other emergencies.

Natalie and Dewey discuss why cold-water samples should be allowed to warm before testing, why commercial plunges should strongly consider supplemental treatment such as UV, ozone, or advanced oxidation, and why a quick pre-entry rinse can remove a surprising amount of contamination before it enters a very small body of water.

They also address the biggest myth of all: because someone only spends a few minutes in a cold plunge, the risk must be low. The exposure may be short, but the risks are not necessarily smaller—they are simply different.

Topics discussed include:

• Why even healthy, conditioned athletes can experience emergencies
• The dangers of using a cold plunge, pool, or spa alone
• How cold temperatures affect water-testing reactions
• Why cold samples should be capped and warmed before testing
• Reduced sanitizer reaction rates in cold water
• Why small water volume and heavy bather loads create greater risk
• The value of UV, ozone, and advanced oxidation
• Sweat, ammonia, urea, dirt, and everything else bathers drag into the water
• Why pre-entry showers matter
• How a simple rinse can substantially reduce contaminants
• Why short exposure does not automatically mean low risk
• The importance of supervision, maintenance, testing, and operator diligence

The takeaway is simple: be diligent. Know what the water is doing, test it regularly, maintain the vessel properly, and never assume that experience or physical fitness makes someone bulletproof.

Download the Cold Water Venue Guidance from the Council for the Model Aquatic Health Code.

Natalie also shares an update on her Tennessee Triple Crown Open Water Swim Challenge. She will swim more than 21 miles across three open-water marathon events to benefit Every Child a Swimmer through her fundraiser, She Swims So They Can.

Special thanks to campaign sponsors Revved Up Apparel, H2Flow Controls, Tenjam, and Talking Pools Podcast.

Transcript

SPEAKER_06 0:53

Before we get into today's episode, I want to take a moment to recognize the incredible companies supporting my Tennessee Triple Crown Open Water Swim Challenge, benefiting every child a swimmer. First, I'd like to thank Revip Apparel, the official apparel sponsor of the campaign, and H2 Flow Controls. Thank you both for believing in the mission and helping making this possible. This week, I'd also like to give a very special shout out to two more amazing sponsors who have joined the journey. Thank you to Talking Pulls Podcast for supporting not only this fundraiser, but for also providing an incredible platform to share the mission with the aquatics industry, your support and encouragement, being more than you know, and I'm truly grateful to be a part of the Talking Pools family. I'd also like to thank Tenjam for coming on board as a sponsor. Your commitment to supporting water safety and helping every child a swimmer, provide life-saving swim lessons is greatly appreciated. Thank you for believing in this cause and for being a part of this journey. I also want to say a heartfelt thank you to everyone who has already visited the public donation page, made a contribution, and left such kind and encouraging messages. It's truly meant the world to me, and I sincerely appreciate every one of you. Your support and encouragement continue to motivate me as I prepare for these swims. As many of you know, I'll be swimming more than 21 miles across three open water swim marathons to raise money for every child to swimmer through my fundraiser. She swims so they can. Donations will be accepted through October 3rd following my final marathon. And for those asking, my swims are September 13th, September 20th, and October 3rd. And if your company would like to become a sponsor or if you have any questions about the campaign, you can reach out to me directly at nhood at thegritgame.com. You can also visit my Facebook or Instagram pages to learn more about the fundraiser, make a donation, or purchase the official fundraising apparel. And if sponsoring or donating isn't possible, sharing the fundraiser is just as meaningful. Every dollar helps, every share makes a difference, and together we can help ensure more children have the opportunity to learn this life-saving skill. Now let's jump into today's episode.

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SPEAKER_06 7:13

Dewey, welcome back to the Talk and Pools podcast.

SPEAKER_01 7:17

We now join part two of our two-part Coldwater Mythbusting plunge episode with Dewey Case of the Council for the Model Aquatic Health Code in progress.

SPEAKER_08 7:38

Anyone using it can wind up in a situation where they need some assistance to get out or someone to intervene. And it may not even be the cold water necessarily. So let's say again, you wake up, you do your HIIT training, drop, get into cold plunge, you're uh you ate a salad last night, or you're cutting for a bodybuilding competition. And so you're cutting period where you're trying to shed that sub Q body fat and make your muscles pop, and you're not eating carbohydrates. In there, don't want to go back. So you work out, you get in the cold plunge, and while you're in the cold plunge, guess what? Your blood sugar crashes. Yep. So that's not an impact of the cold plunge, and it's a normally healthy person. But it's just an example of how, you know, these things can be situational. And a lot of that is because, yes, we are talking about health conscious individuals. We are talking about those that are typically going to be in better physical shape. Right. But we all know athletes, we all know people that you know they're in extreme physical shape, they they are healthy, but because they skip breakfast, they pass out. Yeah. Now when you go back to the rehab aspect, here's the thing that is interesting, because I do want to loop back around to that. It's interesting in that A, they're highly supervised for one. Yes, that is true. I just thought it interesting. I was like, whoa. Yeah. Well, what the data shows is that uh so when you have someone who's you know coming in, they're on their hold, they're detoxing, they're coming off of whatever uh their particular, you know, substance was that they were abusing, right, immersion in a in a cold plunge has been shown to release dopamine, lower depression, increase mood, help with sleep, and have significant psychological impact.

SPEAKER_06 9:40

Okay. Yeah. I take back what I said. I okay. Okay. I I was reading that and I was just like, I have to I have to bring this up to do it. But okay. In that case, I am for that then. Okay. Very cool. So definitely cold plunges aren't one size fits all. So just be careful, you know, just be careful. And as you said, definitely make sure you have someone with you. Um, same thing as when you're swimming, have someone with you. I mean, you have to be safe.

SPEAKER_08 10:09

Same thing, Natalie, as in a spa. Yes. Right? You don't swim alone because anyone can drown. And any, you know, good lord, look at Fran Krippin back in 2010 or so. International top 10 open water swimmer. Yes. Overheat and drowned in Dubai.

SPEAKER_06 10:25

Well, I mean, I'll tell you, I'm I'm a darn good swimmer, but just in this training alone that I'm doing for the Triple Crown, Tennessee, for the the fundraiser for every child of swimmer, I'll tell you, a couple weeks back, I uh I I went, oh, I must have been 40 meters. I hadn't taken a breath. And it dawned on me, I had I had taken in so much air that my my system just was starting to shut down. And I stopped mid-pool and I stood up and the lifeguards were staring at me and they were like, wait, what's she doing? And I was doing a very long swim that day. And I think I had, I think I'd gone, I don't know, maybe I think that was like a 10,000 meter swim for me that day. And I was at my second point, so I was about, I don't know, 6,500 meters in. And I stopped mid-swim and I went, oh, we're done today. Yeah. That shouldn't be happening. And it just, I was, you know, in my own zone and just kept going. And I was like, wait a second, why aren't I breathing? Why don't I want a breath? And I stood up and I wasn't out of breath or anything. But then when I got out of the pool, I was like, oh, we're done. We're we are done. We're done. So you always have to have someone around you. And I actually didn't know.

SPEAKER_08 11:39

Well, that was definitely you know, that's a great story. And I've I've got another story I'll share similar to that. You know, we we get in this mindset, it won't happen to me. And that's exactly what happened. That happens to other people. I have we know I know someone who is relatively well known in the equal in the aquatics industry that uh decided to have uh an adult beverage in a spa and they passed out. Yeah. And they fell out of the spa. Right? And this is someone, thankfully, they fell out and not in. Well, that's someone who's well versed on aquatic safety. So that's a cautionary tale for everyone, right? No matter if you're in a coal plunge, specifically for this conversation or a pool or a spa, you're not immune to mother nature and physiological responses.

SPEAKER_06 12:31

No, you're not. I mean, you're exactly I never thought it could happen to me. And it took me a few days to get out of my head because the next day, when I finally got back, well, not the next day, I took a day off, but when I finally got back in the pool and I started swimming, it was then in my head and I was so focused on my breathing. I was like, Am I breathing too much? Am I taking in too much air? Am I pushing enough air out? And finally, I was like, Natalie, cool it, you've been swimming for years, and then I'm back out of my head, but you're absolutely right. It can happen to you, so don't think it can't.

SPEAKER_00 12:58

Yep.

SPEAKER_06 12:58

So you got to be careful. But well, another one is kind of moving along is that testing cold plunge water is no different than testing a swimming pool. And looking at the guidance, it recommends warming the sample before using mini test kits because cold temperatures can affect accuracy.

SPEAKER_08 13:19

Yeah. Yeah. It's uh we spent a lot of time talking about that. And we actually, um, they're not CMAC sponsors. They didn't, uh they didn't sponsor, you know, any of this work, but they were a resource. Yeah. So we actually consulted with Taylor, uh, Taylor Technologies. Uh-huh. And, you know, got, you know, confirmation from, you know, one of the largest, if not the largest, you know, test kit manufacturers in the US.

SPEAKER_06 13:47

Yeah.

SPEAKER_08 13:48

You know, them Lamont Halen test are the big three. But, you know, we got confirmation that yes, at temperatures that low, you know, the and it's really the reaction. It all goes back to this metabolism. Right. The water so the water temp is so low it slows all of the reactions, so you don't get an appropriate reading. So they recommended warming it.

SPEAKER_06 14:11

Wow. I love it though. I love it. No, and I didn't see, did they I I don't remember, did it say what to warm it to or what degree? Up above 60. Above 50. Okay. Very cool.

SPEAKER_08 14:25

I love it. Which is really, you know, so if you're a pool tech, you know, take the sample, set it off, don't set it in the sun, because I need to change the the parameters. Right. Take the sample, set it off to the side, and let it get to room 10, it won't take long. It only takes, you know, a few minutes. Yeah. Ten minutes max. That's not gonna significantly change the water chemistry. So I I I know I was kind of talking with Rudy about this, and he suggested capping the water to prevent off-gassing and chemistry changes there.

SPEAKER_06 14:55

Yeah, there you go.

SPEAKER_08 14:57

That's a good consideration to think of too. Yeah, but definitely let it come up to room 10. Hold it in your hands for the the comparator vial, hold it in your hands for three to five minutes, let it go. Then test, and then you'll have a pretty accurate, you know, testing. Very cool.

SPEAKER_06 15:14

I know it, love it, love it.

SPEAKER_08 15:16

Yeah.

SPEAKER_06 15:17

Well, another one. And it's easy.

SPEAKER_00 15:18

The thing is, none of it's it's hard.

SPEAKER_06 15:21

Yeah, and that's what's so great about it. It's easy. Yeah. And it's there. And this beautiful guidance. I love it. It's awesome. So another one is that, um, and this one I really like. It's commercial cold plunges don't need secondary treatment. And the guidance recommends strongly considering supplemental treatment like UV, ozone, or advanced oxidation. Can you explain a little why that recommendation made its way into the document?

SPEAKER_08 15:51

So one is because of the nature of it, because it's a small volume of water that's volatile, you know, largely the committee decided to treat this as an increased risk vineyard. Okay. Meaning that because of and and to kind of cut that into a a simple sentence, because of the dynamics of this body of water, there's a higher likelihood of illness.

SPEAKER_06 16:15

Makes sense. Yep.

SPEAKER_08 16:16

Small body, you know, the proportion of father to water is is is, you know, not uh it's definitely a skew. It's a lower proportional thing. So you don't get solution by dilution. Right. So considering an increased risk venue combined with the fact that we know that your traditional halogen-based sanitizers, chlorine, bromine, et cetera, slow down and become less, I won't say less effective, but less slow to react. Right. Made that decision to put secondary treatment systems on, you know, kind of a no-brainer. Because there's one thing about UV and ozone and AOP. They don't care what the water temp is. Right. That's true. Ozone's a gas. The gas goes in, mixes with the water, it just kills everything, right? Yeah, I'm becoming Natalie just as an aside, I'm becoming more of a fan of ozone because of its superior killing capacities over UV, but it has its own headaches. It does. Yeah. And and UV's still a good, good, good product. I'll take UV over nothing any day. Right. You know, that's kind of an interesting aside. But UV, as long as you have the right UV transmissivity, it doesn't care what the water temp is. That water temp doesn't change the ability of the UV C wavelength generated by that UV system to penetrate that body of water. Right. And then AOP is its own little beast with its hydroxyl radicals. That's right. Which again, they're not temperature dependent.

SPEAKER_06 17:48

Right. So it's just that that additional you know, protection.

unknown 17:52

Right?

SPEAKER_06 17:53

Yeah, additional protection.

SPEAKER_08 17:55

I mean You know, and and there's a big and here. So we go back to the environment these things are used in, right? Typically athletes. We've got the defensive line for uh Georgia Tech. They're going into their, they've got through their training, you know, the entire defensive line gets into their, I'm making this up. Their 10,000 gallon coal spot. Yes. You know, and uh they get out, they're sweaty, they have all that ammonia coming off their sweat, all that urea coming off their sweat, and that is known to impact water quality. Yes. Well, what's one of the biggest destructors for ammonia and urea and combined chlorine, your chlorin's secondary treatment systems.

SPEAKER_06 18:41

Yep, exactly. Yeah, well, not to mention all the dirt and whatever else they brought in from, you know, out there in practice.

SPEAKER_08 18:49

And cheek wash and everything else.

SPEAKER_06 18:51

Yeah, yeah, yeah.

SPEAKER_08 18:52

No, you know, a little bit of vomit on their shorts when they puke, you know, doing whatever the Georgia Tech defensive line would do in you know, in practice.

SPEAKER_06 19:01

Well, hey, and um the same thing can go for the the marathons or the triathlon people because it's a thing, especially when you ingest too much water.

SPEAKER_08 19:10

Or think about like the really specialty races, your Spartan, your Warrior Dash.

SPEAKER_06 19:14

Oh yeah, the Spartans.

SPEAKER_08 19:16

Think about those.

SPEAKER_06 19:17

Oh yeah. Uh that Spartan race, I I don't I still that one haunts me to this day.

SPEAKER_08 19:23

Yeah. When I when I was younger and fitter, my wife and I, Lisa, we did Warrior Dash. I have not done that one. Yeah, it was fun. Uh I don't I I'm assuming it's still a thing. We did it, we checked it off the list, okay. Yeah, but you know, at the end of the day, end of the race, we're muddy. We got mud in areas that we never thought we could get mud in. Yeah. And they're hosing us off with a fire hose.

SPEAKER_06 19:48

Yes. I did a tough mutter. I did the tough mutter many years ago, and it was kind of similar to that. But yeah, I actually I saw an ad the other day for it was like a tough mutter or something of, you know, I've done the Iron Man, I've done the Spartan, I've done the tough mutter, and it was something different. And at first I was like, I could do that. It was after my uh my three marathon swims, and I was like, I went to look into more information and I was like, nope, no, no, no, we're gonna take a break after the marathon swims. But it was kind of like that.

SPEAKER_08 20:21

But but that's why secondary treatment is so important on these.

SPEAKER_06 20:26

Yeah, definitely for those cold water venues, you know, as we're still learning more. So this one, again, this was I you can I can scream it from the rooftops, but again, I don't know if people are gonna listen. Pre-entry showers aren't necessary. Obviously, we know how let me throw my pen down. Yeah, we we obviously let's let's just get about it. I mean, off you gotta rinse off, you gotta rinse off. Are people gonna rinse off? No, but you gotta shower. I don't know why people don't think this is a thing. They're just like, oh, it it doesn't really matter, you know, it's even if it's just me, but just shower. Come on, people.

SPEAKER_08 21:03

You know, that's it's interesting. And and we know that showering, a full-body soap shower, wash your butt crack, you know, we wash your pits. We know that that is best practice for every bit of wreck water, foot featured feature, you know, man-made, filtered, treated wrecked water you can get into. Whether it's a lagoon, a spa, a cold plunge, yeah, a 50-meter pool. We know that's best practice. It's interesting because if you go to Europe, ever nobody walks on the pool deck with their shoes for one, right? Especially if you get into Germany, France, Austria, and even England to a certain degree, they don't walk on the their street shoes on the pool deck. They all shower before they get in. Period. Like if you go to hop into a 50 meter in Germany without showering, like you're gonna have Hans is going to come out and drag me to the shower, you know, while Fritz and Greta are staring you down because you're a lazy American who doesn't care.

SPEAKER_06 22:13

Yeah. It's a care, it's normal.

SPEAKER_08 22:16

Yeah. It's normal. And the interesting thing, and I've I've spent a lot of time trying to think about what the difference is. The difference is in America, we go, I am clean, I'm not dirty, it's okay for me to use it. Right? In Europe, and I'm not saying Europe is I'm not getting to uh USA or Right, right, right, right. Yeah, yeah. But just from a cultural standpoint, in Europe the the mindset is I'm clean, but I want to make sure I'm clean enough. Right. And then they shower, then they get in. Yeah.

SPEAKER_06 22:55

No, you're absolutely right because that's what everyone here is saying. I mean, again, this morning, I did a long swim this morning. I told you before we got on, I ate my weight and pasta. I was moving a little slow, but I think I saw one person shower. One person shower. And I was just like, great. So I'm swimming with all of these dirty people. That's what I have in my mind when I'm, you know, getting water in between or taking a small snack, which I love when people stop and stare at me that I'm like, I have this like pack of snacks with me when I swim now. But um yet no one's swimming, but you're absolutely right. I'm just swimming with a done a bunch of dirty people. That's really what it is.

SPEAKER_08 23:33

And look, we us as Americans, it's part of our culture. We we just don't do it. You don't shower before every swim.

SPEAKER_06 23:41

Not every.

SPEAKER_08 23:44

We can go through the laundry list of folks that we know in the industry. They don't shower before they swim. It's a it's an American thing. But that doesn't mean that just because we don't do it in America, the data's wrong. We know from European data, scholarly articles, peer-reviewed, right? Not Joe Blow spouting off stuff he doesn't really understand. We know from data that just taking a simple rinse shower, not even soaked, removes 60% of contaminants from the body. Right. Right. That's huge.

SPEAKER_06 24:23

Well, and huge. No, you're right. I mean, I'll say I typically do very early morning workouts, but if I do an afternoon evening workout, you better believe I will be washing off before I get in that pool.

unknown 24:36

Yeah.

SPEAKER_06 24:36

Because I've c I've come in uh close counters with my children and uh they've been at school. So who knows what they've come against. But yeah, I mean, just just wash off. I will say though, going before we move to uh one of our last myths, is that at one point I talked about cologne guy. He was a thing, he always showed up, he wore cologne. I could taste him, um, which is kind of weird, gross to say. But I could take I could taste the cologne when he entered. He doesn't wear his cologne anymore, and he showers before he enters the pool. So, and he listens to this podcast. Um so thank you.

SPEAKER_08 25:17

I appreciate not cologne guy on behalf of pool operators across the country. Props to you, my friend.

SPEAKER_06 25:24

Thank you. I appreciate not tasting your uh cologne, which would it probably smells great, just doesn't taste good when I'm swimming. So thank you, sir. Very much appreciate you. And if you beat me again in the next swimming yeah, don't anyways, it's on. Anyways, the the uh the last one we'll finish uh let's finish this this this one. I think it kind of really ties everything together, and it's um cold plunges are low risk because you're really only in them for a few minutes.

SPEAKER_08 25:53

No, I'm gonna burn some crap out of that one. I think this entire discussion we've had, you know, eliminates the idea that they're low risk. Right. But yes, in certain situations, if you're adequately supervised, if the water is adequately treated and maintained, if the vessel itself is adequately clean, and if you are healthy and not in a metabolic crisis, and not uh not have don't have metabolic syndrome, rather. Right. You know, there's not a significant risk. Right. But that's a that's a very, very far cry from saying they're low risks.

SPEAKER_06 26:33

Right. No, I would absolutely agree. I I mean short exposure, it it doesn't mean that it doesn't necessarily mean low risk. It just means the risks are different.

unknown 26:43

Absolutely.

SPEAKER_08 26:44

Just because you don't you don't get in the water and walk out with Ebola doesn't mean that it's a healthy situation.

SPEAKER_06 26:50

Right. I I mean risks are different, they're not smaller. I mean, and that's why this new guidance is such an important resource for our industry. I mean, I know I've already learned so much just in this episode, so I I can't thank you enough. Well, do we before we wrap up, if there was one message you'd like, you know, every owner, operator, designer, builder, inspector, or public health official to remember after reading this guidance, what would it be?

SPEAKER_08 27:18

Be diligent. Yep. Be diligent.

SPEAKER_06 27:22

That's it. I would agree. Be diligent.

SPEAKER_08 27:25

You know, we we try to we try to make these things, and we're both into industry. We can go into, I was working someone through a PowerPoint presentation yesterday, you know, Uber detailed about stuff that most pool operators never have to worry about. We can make this thing so complex sometimes that it's crazy, and I'm the world's worst about it. Because I love going into the nuance and the detail and the what-ifs and spending an hour talking about coal plunges versus reading a document in five minutes. Um I love that. But at the end of the day, you know, for any commercial pool operator, for any homeowner, just be diligent. Yeah. You don't need to spend hours on this stuff, but be diligent. Be aware, know what your water's doing, test it on a regular basis, do those small little habits that say, hey, this is a healthy body of water.

SPEAKER_06 28:23

Right.

SPEAKER_08 28:25

Be diligent. That's it.

SPEAKER_06 28:26

Yeah. Yeah. And, you know, I really appreciate this guidance because, again, it's not about discouraging cold water immersion. It's about helping the industry better understand it. And, you know, if you have not downloaded, I would definitely rec highly encourage you go and download it, read the new CMAC cold water venue guidance. You know, whether you're an operator, service professional, health official, manufacturer designer. There's definitely something in this document for everyone. Definitely. CMAC.org, and you can download it from the front page. Yep, cMAC.org. You got it. Well, Dewey, thank you again for spending time with us. It is always a pleasure to have you on and for you to share your expertise with us. I cannot thank you enough, my man. Anytime, Natalie.

SPEAKER_08 29:16

Always a pleasure to be here.

SPEAKER_06 29:18

Thank you. Thank you. Well, and to all of our listeners, thank you again for tuning in. Again, go and download that cold water venue guidance from cmac.org. And uh thank you for tuning in. Keep uh challenging those myths, keep getting educated and continue to make our industry better. Until next time, guys.