Dr Mark Harper Banner

My guest today is a consultant anesthetist at Brighton and Sussex University Hospital who, accidentally and via unrelated routes, has developed an interest in the negative effect of getting cold during surgical operations and the positive effects of cold water swimming. With his new book out CHILL, he shares his journey into the amazing impact cold water swimming has had on him, and others with anxiety and depression, PTSD, migraines, autoimmune disease, and more. Mark shares a step-by-step explanation of how to get started swimming and what you need to do before and after you get into the chilly water. He also shares that it doesn’t need to be icy cold to gain so many benefits from a weekly swim. His passion is infectious. Enjoy.

Listen to the episode here:

[podcast_subscribe id=”5950″]

Key Topics:

Brave the Chill: Cold Water Immersion for Depression & Anxiety, with Dr. Mark Harper

At that point, I thought, “Maybe we could use cold water swimming as a treatment for depression.”

“When I come out of the water, I feel alive, alert, and have a sense of euphoria and achievement. The act of taking a pill is never going to give you that and that’s what you get from the swim.”

My guest is Mark Harper. Mark is a consultant anesthesiologist at Brighton and Sussex University Hospital. After he became an anesthesiologist and was in school, he was trying to study the negative effects of getting cold during surgical operations. I don’t know if you’ve ever come out of surgery and you can be freezing cold. They give you those shiny blankets but inadvertently and unrelated, this brought him to the positive effects of cold water swimming.

He has a new book out called Chill. He shares his journey into cold water swimming, and the amazing impact it not only had on him, but on others, people with anxiety and depression, PTSD, migraines, autoimmune disease, and so much more. If you think, “This is for me. I can take this on once a week,” he also breaks down for us with a step-by-step explanation of how to get started swimming in cold water. Maybe it feels intimidating, but he makes it achievable and it doesn’t have to be ice water.

He’s saying, “Everything under 68 degrees, you can get a lot of benefits from. If you can get in there once a week, there’s a community aspect.” He breaks it all down. He is passionate about swimming and there are over 7 million people in England alone that are doing this. We’ve all heard of this with Wim Hof and everybody’s icing and doing Qi and this is another way to support ourselves and our well-being. I hope you’ll enjoy it.

Dr. Mark Harper, thank you, and welcome to the show. I’m excited about your book, Chill. We could all use a little more of that. It comes out on July 12th, 2022. Maybe you could share your journey from being a doctor of anesthesiology to this other new additional part of your life. You were compelled enough to write a book. I always think people are committed to something when they write a book so maybe you could share your journey.

It’s a bit of a long and winding journey, which goes back to going skiing. I was in the middle of my specialist training as an anesthesiologist and I decided to take six months off and go and work in the ski resort. It was nothing anesthetic. I was just guiding people around the mountains enjoying the snow. Before I went, my program director rang me and said, “You should apply for this job.” I said, “That’d be nice but I’m going skiing instead.” He said, “You’re not going to advance in your career very much,” in the nicest possible way. He was a great guy.

Ironically, nothing has had more effect on my career than that. Off the back of that and started organizing a meeting in that French ski resort. The first time we held the meeting, I thought, “I’ve got to find a subject that is relevant.” I thought, “Hypothermia. That’s a relevant subject.” From that, I went on to research hypothermia during surgery. Getting cold is always bad for you. Exposing yourself to that cold, that’s what we’re talking about here. Getting cold, no. When you get cold during an operation, that’s bad for you because you’ll have more complications. It increases the stress on the system and you get more complications.

While I was researching this, I started coming across articles about cold adaptation and how people adapted to cold water swimming. I looked at it and was like, “In my patients, I want to reduce the stress response.” We all need a stress response. Evolutionarily, it keeps us alive but we don’t want too much of that stress response. What I want to do is reduce the stress response in my patients.

Although you don’t feel anything, when you have an operation, your body reacts as if it’s still having this massive insult. You get all those things like inflammation and things like this that go crazy. I thought, “With the cold stress response, that’s the same as the surgical stress response. If you adapt to the cold, that gives you a reduction in the stress response which would be good for my surgical patients.” That remains only theoretical. I published a theoretical paper on it.

[bctt tweet=”Taking that chance, getting through that challenge and getting out, that’s what’s good for you.”]

That is interesting. Before we leave there, one of the scariest things about getting surgery is being put under. They’re talking about controlled death. For a lot of people, that’s one of the scarier elements of it. I’ve never heard of somebody who’s in that part of the practice thinking way ahead. For example, if you’re having orthopedic surgery, a lot of times, your doctor might say, “Let’s get that muscle as strong as we can before you come in and we do this surgery so your rehab is better,” and things like that. As a young person, I’m curious about how you were thinking. Were you able to have access to patients weeks prior? Were you thinking, “I’m going to be able to talk to patients weeks before surgery.”

That’s what we do and there is a broader movement now towards what’s called Prehabilitation. It’s like what you’re saying. It’s getting your cell fit and healthy before. What we want to do is reduce that inflammatory response and no one’s done this yet. We do have clinics now where the patients come in 2, 3, and 4 weeks before surgery, and so we do have access to them. However, no one has taken on my theory to try it out in practice yet.

Where you live you might be ahead of where we are a little bit in the States, as far as connecting all the elements to health, healing, and such. I’m curious. Besides the movements, do you add the other components of health? Do you talk about an anti-inflammatory diet or anything like that to the patients prior to coming in? It’s like what you said, is that still not widely adopted yet?

Unfortunately, it’s still not been widely adopted. There are a few things. In fact, the things that are done are not drug-related but they’re things like how you have a drink before you have. You have a sports drink before you start and things like this to get your sugar levels up before you start so there are a few things that are not anti-inflammatory at all.

What you were seeing was a lot of patients after surgery. I’ve experienced that after surgery you do get cold.

People expect pain after surgery. People sometimes might expect to be a bit sick after surgery but a thing that people don’t expect is being cold. That’s one of the worst feelings. I’ve spoken to many patients about this and the worst thing is, is this unexpected shivering and being cold afterward.

In this theory of yours, this led you to think about ways or what environments or elements people could do to get that adaptation. What was that journey like?

That was that part of the journey. The next stage of the journey is my journey to look at mental health. I’m an anesthesiologist. I use drugs. I put people to sleep. I don’t talk to them. I don’t deal with their mental health except in that quick interaction so it’s an important interaction, but it’s not a long interaction I have with them before they go off to sleep.

That came about because I’m a swimmer. I grew up swimming. That’s my exercise. How I keep fit is by swimming in the pool but then I was complaining in my mid-30s. I started what you call attending in Brighton as a consultant and anesthetist. I was complaining to an old friend of mine, “The swimming pool shut for two weeks. I’m going to be bored. I don’t like it.” He said, “Go and join the sea swimming group.” I didn’t realize the club had a sea swimming group. I said, “When did they swim?” “7:00.” “When?” He said, “All year-round.” “Really?” I was as shocked as anyone.

That first time, two weeks in the summer, top of the temperature at twenty degrees about 68 Fahrenheit wasn’t cold at all but I still remember after my first swim. It was probably a kilometer and a half swim. It was nothing particularly much. I was walking up the beach and thinking, “I feel good.” I was amazed. I wasn’t expecting that.

A few years later, I read an article in a newspaper. What this did was it linked inflammation with depression. It described depression as maybe an allergic reaction. Knowing my stuff now from what we call Perioperative Hypothermia, one of the main reasons or theories that it would work for my surgical patients was that it reduces your levels of inflammation.

You want inflammation. It’s the first line of defense but you don’t want too much of it. You want it in the good physiological zone, not the bad pathological zone. I feel so good when I go for a swim. That’s why those two weeks have become more than twenty years. I thought, “If you can adapt patients here and you reduce their inflammation through cold water adaptation and depression is linked to inflammation, maybe we could use cold water swimming as a treatment for depression.”

How do you pitch this to somebody?

I’ll tell you the story. The way this came about and after that was that I met this guy, Professor Mike Tipton. He’s a great guy and a good friend of mine now. The first time I met him, I pitched this idea to him. He is the guy who’d been doing all the studies on cold adaptation. He is the guru of cold adaptation and he’s a physiologist. I pitched this idea to him and he said, “That’s interesting. I had not thought about that but I liked that.”

A couple of months later, he was contacted by a television doctor, Chris van Tulleken, who had this idea about doing a program, The Doctor Who Gave Up Drugs. He said, “Is there anything that we can use cold water for?” He said, “It’s funny that you should say that because I’ve met this guy who thinks you could use it for depression.” The pitch went out and they tried to find it hard to find a patient with depression who is willing to come on TV. This was Sarah. She was 24 at the time. She’s been on antidepressants since she was sixteen. Her father committed suicide, her brother died of an overdose and she was a single mom but she was determined not to let her daughter grow up with seeing her mum take pills. It was pitched to her by the BBC and Chris van Tulleken.

Dr. Mark Harper Photo 1

Dr. Mark Harper – We know that going outside is good for you. We know it as blue water therapy. A view of water has an additional effect.

We’ve had an icing practice at our house for more than eight years. It’s three minutes in the ice and we always joke that you’re happy to be alive when you get out. There’s hormone regulation and maybe an order of importance. You’re under threat, and to your point, your body adapts. All of a sudden, certain things go right out the window and you’re in the present and these things. Getting people into cold is so interesting because there is so much negative talk around cold like, “Don’t get a cold.” “Watch out. You’re going to be cold.”

What’s important is when you get introduced to this, at least from our point of view, I see that in your book, Chill, you talk about this where it’s getting people to understand that it’s an okay threat and it is going to be cold and you can survive it. How do you propose? I know Sarah was motivated by her own experience and then with her daughter, but what is your way of coaching or making the transition for somebody who’s going to do this for the first time easier?

The bottom line is you’ve got to go in with it being clear. You don’t have to be in for too long. It doesn’t have to be too cold and you don’t have to do it that often to have a good effect. With everything, it’s honesty. I remember when I was a junior doctor having to give patients bad news. I worked in intensive care. Their father or their loved one was dying. I was always honest. I was always open. The number of times people came back to me saying, “Thank you so much. We appreciate that.” It’s a horrible business but that’s what they did. It’s going in and it’s preparing them for, “Yes, it’s going to be a hard experience.”

Even after more than twenty years, I still hate getting into the cold. I hate getting into it. I know what’s on the other side and that’s why I do it. It’s saying, “This is going to be a bit like a panic attack because you start hyperventilating.” You’ve got to realize this is it. You won’t be able to control your breath but a little later, it doesn’t take long. A minute or so you stay in that little bit longer and your breathing will come back under your control. That’s part of it. It’s part of this challenge. You overcome the challenges. You say, “That was so scary.” That scariness is enhanced by hyperventilation and the seeming panic attack. Go and stand on that lot that bit longer and you will see it pass.

You said that it has a metaphorical component to it when you face these things that are ultimately positive, but uncomfortable. This isn’t damaging, it’s not an argument with a loved one. It’s not a bottle of whiskey. It’s uncomfortable, but it’s ultimately supportive. When we face those, it’s a practice that we learned how to lean into other things that are uncomfortable in the things in our regular life, whether it’s uncomfortable conversations with a loved one or something at work.

It supports that skill a little bit and we wouldn’t necessarily draw the line from, “I go cold water swimming,” to, “I lean into things or try new things that make me uncomfortable or speak my mind,” or even things like that but it’s a practice that helps. You take Sarah but she went more frequently in the beginning. In your book, you’re talking about how even once a week is wildly beneficial. How does that work? Is it like, “Try to do it more often in the beginning.” How does that work?

We had to do it all in one go with Sarah because we were filming it for the BBC and that was it. What we did was on the first day we went into the pool. Mike in Portsmouth has got these extreme environment labs. It’s an amazing place. You can adjust the oxygen levels, the temperature, the humidity, and all these things. You’ve got an endless pool there. We took her in and adapted there for over a day. That was interesting as well because, after the second time, she said that she didn’t want to go back in. We said, “That’s fine. Just take your time. It doesn’t matter.”

This is coming back to your earlier point about how you pitch it to someone. You’re honest about it. She said, “I’ll go back in one more time, eventually.” We let her do her thing. No force at all as you went back in. She was like, “This is good.” She enjoyed it. Something we should take in is that, for the first time you are ready for, “I’m doing it.”

The second time, that’s the worst. On the third time, you begin to get the hang of it but this seems to work. We did that for over a day and then the next day we went out and swam with her in a lake. This is the same even if you do it every week. Once a week, I reckon, is enough. Some of the cold water adaptation programs that have been used experimentally do take this approach. If you do it once a week, the second time is probably going to be the worst, but so it’s a matter of sticking with it. One of the key things I try to get across is you stick with it. You do it and say, “I’m going to do it six times.” If you don’t like it after that, you’re not going to like it.

[bctt tweet=”It’s safe for most people as long as you follow a few simple rules and the rules are common sense.”]

I don’t want to say a toolkit but you’re giving people a bathing cap and knowing your exit. You take away some of the other barriers. Do you suggest a bright color cap because of keeping the heat so people can see you? What exactly are the things that you like for people to have?

The hat is for both of those things. One, you’re easily visible and that’s great and the other thing is you do lose heat through your head. Interestingly, there’s a classic thing that you lose 95% of your heat through the head but that comes from a study where people were in full immersion suits, the only part that was exposed was the neck and the face but you do lose proportionately more heat from your head.

That figure is a myth, but you do proportionately lose more heat so that’s a good thing to have because you don’t want to lose it. Putting your face in the water is important. We can come on to why that is later. For the rest of the kit, it’s about making it as good as it can be. You have to expose yourself to that challenge but when the water is below ten degrees, I find it so cold and my hands and my feet, that I wear gloves and shoes and I’m sure you get the benefit. because basically, you’re putting your body in, that’s what’s giving you that strong reaction. It’s not the pain, it’s not getting into ice. You don’t have to get into ice.

I do that too. I’ll be honest with you. I do a lot of icing and sometimes my hands will be the thing that gets me out of there quicker. I worked my feet into it and they adjusted very well. There have been suggestions that maybe it’s circulation. You improve your circulation so that burning diminishes. I don’t know if you ever find this but sometimes on some days, when it’s cloudier or it’s later and I’m tired, my tolerance is less. I want to remind people when they experiment. I’d love to hear what your feelings are.

Earlier, when we have a little more energy and we have a physical tolerance, it does make it a little easier but also the things that will get you out, for me, if it’s my hands, there are days where I slide my hands out from sitting in the ice. I go, “The thing that is going to trip me up right now is my hands,” and I slide them out. If it’s too cold for you at that moment, it’s putting booties on. If you’ve had a stressful day, it can go either way. This cold therapy can either help put it in perspective and sometimes you don’t have it. If you’ve gotten beaten up by your day, going into the cold feels more intolerable.

You’re right. Temperature regulation goes down when we’re tired. It’s one of the first things to go so it’s not good to go. The other thing is, I stress about going in when you’re warm. The right thing first thing in the morning is if I go in at 7:00 which I normally do before work because that’s great. That means I feel good for the rest of the day.

I have so much energy for the day but on occasion, I’ll go a bit later, and even going at 9:00 feels so much easier. As you say, as you go through the day, you become tired and more tired. Towards the end of the day, it’s going to get more difficult. Cloud again. Sun has a disproportionate effect. I haven’t got the science to back this up but for me having a bit of sun makes such a difference even if the temperature is the same.

I don’t know what that is but I sit in the nice tub in a gray sky. It’s a lot harder. I’m setting this table because if someone is intrigued by this, and I would encourage people to try this, your book is easy to read. I read it in a bit of time. What I’m saying is to also set yourself up if you can at least the initial times for success. Maybe being with somebody makes you feel calm and not agitated. Have these tools and have the right things on. A little sun wouldn’t be the worst and don’t do it after a long day.

I also loved the story where you talked about when bathing suits were created and that’s when people started to swim. I never thought about that. You think, “People have always been swimming.” The case is unless maybe you were working in the water or fishing, I don’t know why you would swim. You talked about how the creation of swimsuits got people in the water. Martha Gunn was almost an original lifeguard. Maybe you could share about Martha Gunn.

Dr. Mark Harper Photo 2

Dr. Mark Harper – Get your face in the water because that stimulates the vagus nerve. It reduces your inflammation directly.

This shows that what I’m doing isn’t original. What I’m doing is adding a bit of science to things but all this was done in the mid-eighteenth century in Brighton. That’s where I live now. There’s a guy called Richard Russell, who was known as Dr. Brighton and he built this thing up here. For the next 150 years, maybe longer, it was a massive thing, all this the spa treatments, the bathing, and things like this. The way he got people in and the way people went into the water with these people called Dippers. Martha Gunn was one of the most famous dippers. The future King George IV came and had his daughter. The story goes that when she was still a baby, she dipped in the sea in Brighton, and that was it.

Swimsuits had to develop. They weren’t swimsuits as we’d think about them now, but that’s when they started to be developed. They get these carriages drawn into the water and they go in one end of the carriage and the other into the water and then come back out again. You have people like Martha Gunn pulling them and making sure they can because people couldn’t swim. They didn’t know what swimming was.

A lot of people maybe don’t have access. You were saying, in England, it’s something like over 7 million people are doing versions of this or at least are doing cold water swims.

It’s incredible how it’s taken off over the last few years.

If people are sitting in Ohio, let’s say, and they’re landlocked, cold showers, Wim Hof talks a lot about cold showers, 30 seconds, a few minutes, and things like that. There are a lot of benefits to that. I would like you to expand a little bit about the benefits of being in the sea, being in a natural body of water, but also touch upon some of the other ways people can get these benefits of being in the cold it can be available.

To understand how to get the benefits of the cold, you need to understand how it works in a way. There are two aspects to the effect this challenge has. The first is how cold the water is and how cold the environment is. You can use cryo chambers, but they’re air so they have to be so much colder because air doesn’t hold as much heat and therefore it doesn’t take away as much heat as quickly as you. That’s why they have to be so cold. The other is the rate of cooling and water takes heat away from you very quickly. What you want to think about is a shower. That probably isn’t as cold as cold water, but it is colder than normal and it doesn’t cool you down as quickly as if you’re totally immersed in cold water, but a cold bath that’s going to be more effective.

A cold bath with a load of ice cubes in, that’s going to be even more effective. You can use these other things. To me, the sea gives it. It’s the waves. It depends on where you are. Where I am in Norway, there are no waves. None at all. Where I’m in Brighton, there are amazing waves and it adds something to it. It’s a bit more of a challenge. You have to think about it. It takes you out of your thoughts, out of all that rubbish going on in your head to think, “There are waves. I need to get in there,” or whatever. That adds something but overall, that’s a relatively minor difference to say going into a river, a lake, or something like that. It’s still outside and we know that going outside is good for you. We know that is.

We know that blue therapy, the view of water, has an additional effect. When we do this thing, if you have a bath or a shower, maybe you do it with someone, I don’t think it’s that much fun though if it’s a cold shower. Getting out and doing it with a group of people makes a massive difference. One, it reduces social isolation which we know is good for you. Two, it encourages you to go back, if you’re with a group of people. In some of the courses we’ve run, and these are for people with clinical anxiety and depression, one of the things they get back to us and say is, “On some days, I didn’t want to go but I couldn’t let the rest of the group down.”

I don’t care who we are. We all need these. I say this all the time. Out of all the systems in place to help us be successful, it’s that accountability and that encouragement. There’s something so powerful about connecting with people around something that ultimately is good for everybody. Also, someone being there for your victory too, “You’ve got this today,” and there’s a beauty exchange and you talk a lot about the importance of the socialization part of this component, which I appreciate. It isn’t about, “Adaptation and inflammation,” but it is talking about revisiting, going into nature, and talking about blue therapy and connecting that community. No one can imagine all of the reasons why people are feeling what they’re feeling, but it seems like a lot of the same things can help whatever it is.

Without a doubt. You talk about how we got all these tools and you talked about how you need as many tools as you can in your toolbox, whether it’s nutrition, this, that, and the other. What you’d get with cold water swimming or outdoor swimming specifically, is a pretty well-packed toolbox. It’s not everything. It’s not a miracle cure but it’s a pretty good toolbox, you’ve got there to be starting with.

[bctt tweet=”To understand how to get the benefits of the cold, you need to understand how it works, in a way.”]

Out of curiosity. My husband and I were talking about the challenge in waves and walking on sand or rocks. There are all kinds of grounding and beautiful things that happen to you. Do we know if there’s any difference between being in salt water versus fresh or ice baths or is it like, “Cold is cold. Whatever you have access to or whatever tickles your fancy, do that.”

For me, I don’t know of any difference as such. There are those things that you talk about. Fundamentally, there’s no difference with the cold. It’s all the stuff around it. It is the waves so it’s not the saltwater or the freshwater as such, it’s the environment and that means community, as well as the physical environment.

There’s a big difference between anxiety, depression, feeling anxious, and being sad but in the book, you do talk also about people who have chronic pain, migraines, fibromyalgia, PTSD, and autoimmune disease. You guys have been exploring a lot of different ailments that people experienced that this seems to support.

That’s quite interesting because where we’ve come to this is from is in the first study we ran. We had Sarah long and it worked. Just as I was going along for a first swim and all that, I said to Chris, “What if this doesn’t work? My whole theory is blown out of the water.” He said, “Don’t worry. It always works on TV.” After that, we need to do it in real life so we ran these courses in a clinical study for people with diagnosed anxiety and or depression. We had 59 people through that.

You talk about fibromyalgia. There’s a guy there, Martin. He came along because he was anxious. He has been a lifelong worrier who suffered from clinical anxiety. He came along to try and sort out his anxiety but he suffers from fibromyalgia. Coincidentally, he noticed that the symptoms of fibromyalgia got better. He comes out with a wonderful comment, which is, “When I come out of the water, I feel alert, alive, and have a sense of euphoria and achievement. The act of taking a pill is never going to give you that. That’s what you get from the swim.”

We’ve seen a lot of these other conditions being improved by cold water swimming, but most of this has come off the back of a complete coincidence. Beth was the one who had migraines. She was having 28 migraines a month. Just imagine. According to the World Health Organization, that is as bad as being paraplegic when you have migraines as she had. She read about being out in nature and thought, “How can I be out in nature? I can’t lie inside all day.” She and her now-husband said, “Let’s try swimming in the sea for 100 days and make a film about it.” She’s a filmmaker. Coincidentally, she noticed the migraines were getting better. It didn’t fix it but enabled her to get back to school and finish her PhD, which she had to give up.

You talked a little bit about Mike Morris creating The Chill Therapy. People have been doing it. In your book, you mentioned how philosophers are always drawn to the sea. I always find it amazing that we’re so smart now and we live in such a modern way that we’ve forgotten so many basic ways to support ourselves. It’s as simple as being with one another in an uncomfortable environment. We do an ice tub so that’s 32 degrees but 68 degrees would be a lot more fun. Is there one that’s a sweet spot where you’re going, “We’re getting a lot of extra benefits, but it’s not so brutally cold.” Is it 50 degrees? Is there some temperature that is showing up as a great number for you when you guys are doing this?

We haven’t done the studies in the clinical studies we’ve been doing, but they’re too sweet spots you can think about. In the range of 10 to 14 degrees centigrade, that is probably where you get your maximum adaptation. We see we don’t see any more adaptation below ten degrees. Maybe you get more of a physiological effect, but not so much. The vast majority comes by the time we get to ten. Of course, it feels a lot colder and it feels a lot more brutal but also, at 20 degrees or 68 Fahrenheit, you’re getting maximum vasoconstriction. In other words, your body, and your vessels don’t constrict any more than that.

What this shows us is that even at twenty degrees, you’re having a strong physiological reaction so something is happening. That’s the other sweet spot, 15 to 20, where you know below twenty is good. Certainly, from my own experience, it goes a bit above twenty and I love it, but it’s not quite as good and that’s not brutally cold at all. Maybe you’re getting 60% to 70% of effect between 15 and 20 and that’s a pretty good amount and you’re getting at 80, 90, possibly even more effect between 10 and 15 degrees centigrade.

We have people come and do these experiences. Because you talked about breathing, I do want to remind people that we have them concentrate on slowing down the inhales and the exhales because you get this involuntary thing where it’s almost like hyperventilation. You can even see it on their face, their mouth, and everything. That has been helpful to get people to slow it all down and give them something else to think about other than it’s cold. Yes, it is cold. On average, how long are you swimming in the sea? Are you doing it 5 or 6 days a week? Are you doing it that often?

Dr. Mark Harper Photo 3

Dr. Mark Harper – It’s not the saltwater or freshwater as such, it’s the environment. That means community as well as the physical environment.

It varies. It depends on where I’m working. If I’ve worked for half a year in Norway and if I’m working during the winter, it is quite difficult. Sometimes it’s frozen so it’s a bit too much to do. Sometimes I will swim 4 or 5 times a week and that’s great but you don’t have to be in long. What I say to you is to go in long enough to get control over your breathing again. You know how it is. You go in and in that first base you go, “Ah,” and then it gets better.

It’s interesting. I took a load of school kids. I took my son’s class. They’re 16 or 17-year-olds. We did a day of experiments on the sympathetic and the parasympathetic nervous system and we took them for a swim. It’s great because they go in and of course, I tell them all that they’re going to hyperventilate but stay in. They go in, I heard lots of noise and within a minute or so you hear the calm descend upon them, and the laughing and giggling come.

It’s all so much smoother so I would say you do not have to be that long. If you’re in long enough and you get past that initial shock, then that’s long enough because you don’t want to be in so long that you become hypothermic. The pool getting cold is not good for you. Taking that challenge, getting through that challenge, and getting out, that’s what’s good for you.

You are adamant about when people get out that they get dry right away and get into something warm. Something that we try to practice here when we can and it’s different if you’re coming out. Let’s say that it’s winter where you are. You’re in the Scandinavian country so you’re going to be coming out in cold. Something else that we try to practice is when we come out trying to warm ourselves up on our own so that we become more efficient on either side of the spectrum because we do couple the sauna with ice.

My husband will go on the ice first. I don’t enjoy that. I’m not going to lie, I like going into the sauna and then going into the ice but what we try to do is have a little gap in between so that the body has to work a little bit to either cool itself down or warm itself up to maybe become more efficient at that because you are in nature, you are saying, “When you get out, get warm and get dry.” That’s important.

Get out of the wind. The thing is, it depends on how long you’ve been in the water because you can get cold quickly. Once you’re out of the water, it isn’t over. You’ve got your core, which your body’s good at maintaining temperature with but that periphery is like a storage heater or a storage cooler. If that’s all super cold, your body is going to seep into your system. That cold will conduct into the core and you can become cold quickly. It exacerbates being caught in the wind and that layer of cold water on your skin will take a lot of heat out of your body so that’s why it’s important to do it.

It’s good to be warm when you go in. This is why you need to be warm when you go in. Your storage heater is a storage heater. It’s got lots of warmth to give back to you. Whereas if you’re going cold, it hasn’t. The best way to warm up either before or afterward is internally from the inside out. That’s using your muscles so it’s doing your own thing. It’s exercising.

It’s interesting because there’s one study that showed that if you warm up passively so you got a heater or something like that before you go into the water, you cooled down quicker than if you hadn’t warmed up at all. Whereas if you warm up from the inside out, you warm down. If you’ve been in a sauna and you’re warm all the way through, that’s not a problem. It’s when you get a bit cold, warm on the outside, cold in the next bit, and warm in the middle. That’s the problem.

I appreciate you bringing up breathing in using breathing techniques to ramp up or warm up before you go in. I thought that was important. You talk a little bit in the book about cold shock proteins. We hear a lot and there are a lot more studies on heat shock proteins. Besides the inflammation, is there anything else about the cold shock proteins maybe for dementia or things like that?

This is early work. They did a study where they took people who swam regularly in an outdoor swimming pool through the winter in London and they had a control group. This is fantastic. There was a control group. While they were swimming in the water, the control group was doing Tai Chi on the side of the pool. They measured their cold shock proteins.

The importance of cold shock protein is they’re what rebuilds the neurons and the synapses in hibernating animals when they wake up. What we lose in dementia is the number of synapses and so they did show that these were built up in the cold people compared to those doing Tai Chi. It’s going to be good. How good it is and whether it stays off dementia is a study that I can’t see in any way how you’re going to do it, but it’s not a positive thing.

For me, I don’t always need everything to be wrapped in a bow and I do appreciate science but those stories or tales can be inspiring. It’s seeing where things lean towards. People who wait for all the science, that’s a lot of time sometimes because of all those studies. You said that you have a son. Have you ever had a period of time where you didn’t get into the water? You seem like a naturally happy and healthy person but I was curious if you’ve had gaps in your life where you didn’t get to go into the sea.

Guest Book


What I have done is absolutely prioritize getting into the sea. That’s my training. It’s either in the pool or in the sea. That is my number one priority. I can give up everything else and that’s fine. In the busiest times of my life, I get that. There are some days where I have a hard day and maybe it’s been hard at home and whatever. I’ve got to get my swimming. There hasn’t been that long period of time but I do notice it. I do notice when I have it and it’s not great. It’s more about how you can use it therapeutically.

One of the nurses that worked told me that she had a bad night at work. A child had died and that’s truly awful and it’s no one’s fault. There wasn’t anything that anyone could have done but it still feels awful. This was a night shift so 0she left work at 8:00 in the morning and said, “I need a swim.” She’s been convinced by me to start swimming. She went down, had a swim and she said, “That made all the difference.” The one side is you do notice it when you haven’t had the swim but the other thing is, you can realize, “I can use this. I have had a hard time. I am struggling to swim and that does help.”

That’s all I want to talk about. I want to talk about the things that are positive and that we know there’s no downside that can support us. If any of this seems appealing, people listen to things and think, “That’s something that would interest me.” They’re reminded that it’s available, and it’s out there. The book is called Chill, and it’s out on July 12th, 2022. I love the color. I love the blue. It’s so great. Mark, is there anything else that maybe I forgot or you feel is important that you want us that you want to share?

What I like to get across is to keep it simple. One, it’s safe for most people. For 99% of people, it’s probably safe as long as you follow a few simple rules, which are the rules I set out in the book and the rules are common sense. To come back to my comment from earlier, it doesn’t need to be too cold. It doesn’t need to be for too long and it doesn’t need to be too often. Once a week is fine. One thing we haven’t touched upon is also to get your face in the water because this stimulates the vagus nerve and that has a direct effect on your inflammatory system. It reduces your inflammation directly.

What you’re getting with adapting to cold is your baseline levels of stress and inflammation go down and your peaks of stress and inflammation go down so they’re more in that physiological good zone than in the bad pathological zone. That’s a long-term effect. With the face, every time you go in, that is having a positive effect in damping down that inflammation.

When you get into the water, you have to stay in long enough that you get your breath back and you’re past that bad bit. With your face, put it in for a few seconds. It’s not in and out. It’s a few seconds. Let that bad bit go past and then take it out. Roughly, it’s three minutes putting your face in three times. It’s your face, not your whole head. It’s just the face.

That’s a great reminder. If people want to find you or connect with you, where can they do that?

I’ve got basic social media skills, shall we say, but you can find me on Instagram or Twitter @WildSwimDoctor. Also, check out ChillUK.org which is the company that Mike and I set up to run these courses for people. Another great site is MentalHealthSwims.co.uk. They’re a group that I talk about in the book a bit who have set up meetups for people with mental health conditions who want to go and have a swim. It’s nothing formal. Go along and join a group of people.

When it’s cold, you might wear booties and gloves but are you literally in a speedo? Is that what you’re wearing?

Basically. That’s it. It’s getting your body in. That’s the key to it. That’s why I feel so good afterward.

Dr. Harper, thank you so much and I appreciate what you’re doing. The way you’re doing it, this idea, there’s a playfulness and a fun spirit around it. Thank you for your time.

Thank you very much for having me. I was so glad you totally got it. The playfulness and having fun. It’s fantastic to talk to you.

That wraps it up for this episode. Make sure to follow us on Spotify for free episodes and subscribe to the Gabby Reece show on Apple or wherever you get your podcasts. You can follow me at @GabbyReece on Instagram and Twitter. Aloha.


Subscribe to The Gabby Reece Show

[podcast_subscribe id=”5950″]

Resources mentioned:

About Dr. Mark Harper

Dr. Mark Harper Headshot

Mark Harper is a consultant anaesthetist at Brighton and Sussex University Hospitals who, accidentally and via quite unrelated routes, has developed an interest in the negative effects of getting cold during surgical operations and the positive effects of cold water swimming. His professional life and his PhD are based around keeping patients warm. However, his research increasingly involves immersing people (and himself) in cold water in collaboration with the Extreme Environments Laboratory at Portsmouth University. Other roles include being an expert advisor to NICE on a number of perioperative hypothermia guidelines, lead for the Kent, Surrey and Sussex CRN, Honorary Clinical Senior Lecturer at Brighton and Sussex Medical School and Honorary School Fellow at the University of Brighton.