In this episode-inspired deep dive, I share what Janessa and I actually felt and discussed while moving between a 144 degree sauna and a 55 degree cold plunge, and break down what the research really says about inflammation, mood, immunity, and practical safety so you can decide if this therapy fits your wellness journey.
Sitting in a 144 Degree Sauna, Staring at a 55 Degree Tub
When we hit record for this podcast episode, Janessa and I were already 10 minutes into a 144 degree sauna.
Across from us sat a 55 degree cold plunge.
We set a five‑minute timer, agreed that rock‑paper‑scissors would decide who had to get in first, and promised ourselves we would keep talking about the science even while one of us was shivering.
Spoiler: Janessa lost.
You can actually hear it in the audio when she climbs into the cold water. Her voice tightens, her breathing changes, and she says, “I can feel everything just kind of lock up.” That “lock up” feeling is something many people experience the first time they try cold plunge.
But here is the key question we wanted to answer in this episode and in this article:
> Is cold plunge and sauna just a trendy challenge, or is there real, measurable benefit for your body and mind?
As a physical therapy clinic, we don’t want to offer something just because it is popular. We want to know:
- What does the research actually say?
- Where are the gaps in the science?
- How can we use this safely and meaningfully for our patients?
That is what this article is about.
I will walk you through the same topics Janessa and I covered while swapping between heat and ice: inflammation, mood, immunity, and how sauna fits in. I will also share what it actually felt like in the moment.
Why a Physical Therapy Clinic Cares About Cold Plunge and Sauna
At Align Therapy, we help a lot of people with scoliosis, chronic back pain, posture issues, and long‑term spine health.
Our core tools will always be education, targeted exercise, and movement retraining. But over the last few years, more and more patients have been asking about:
- Cold plunge
- Ice baths
- Infrared sauna
- Hot/cold contrast sessions
I am not interested in fads. I am interested in anything that can safely support recovery, resilience, better sleep, and improved mood for our patients.
So before we started offering cold plunge and sauna in the clinic, we did what physical therapists do:
- Reviewed the research
- Tested it on ourselves
- Paid attention to how real people felt and functioned afterward
One big caveat up front:
- Most cold plunge and sauna studies use small sample sizes.
- Many are short term.
- There is still a lot we do not know about long‑term effects in different medical conditions.
So think of cold plunge and sauna as promising tools, not magic solutions.
In Europe, many commercial‑grade cold plunge and sauna systems are CE marked, meaning they meet specific safety and performance standards. Whatever setup you use, make sure it meets relevant safety standards and that you are supervised or educated on safe use.
A Quick Word on the Science (Without the Hype)
Janessa came into this podcast with several papers pulled up on her phone.
A few big themes showed up across the research:
- Cold water immersion can change inflammatory markers and recovery after intense exercise.
- Repeated cold exposure may influence mood and symptoms of depression in some people.
- Some studies suggest potential effects on the immune system, but findings are mixed.
- Heat (sauna) appears to support circulation, relaxation, and possibly cardiovascular health when used safely.
But almost every paper we looked at had the same limitations:
- Small numbers of participants
- Short follow‑up windows
- Narrow groups (for example, only young male athletes)
So if you have read bold claims like “Cold plunges cure depression” or “You will never get sick again,” take those with a very large grain of salt.
Now, let’s break down each major area we talked about in the sauna.
Inflammation and Recovery: Are Ice Baths Really Anti‑inflammatory?
We started with inflammation, because that is what most people think of when they see athletes drop into an ice bath after a game.
What one study on athletes found
Janessa shared a study by Leeder and colleagues that compared professional athletes who recovered with post‑exercise cold water immersion vs those who recovered without it.
They looked at blood markers like:
- Creatine kinase (a marker associated with muscle damage)
- C‑reactive protein (a general inflammation marker)
- Oxidative stress markers
In that study, the athletes who used cold water immersion after a sprint workout showed:
- Better recovery 24 hours after exercise
- Lower creatine kinase levels, suggesting less muscle damage
That lines up with what many athletes report: they feel less sore and more ready to go the next day.
From a PT perspective, that is interesting, especially for people who train hard or are in rehab and trying to manage soreness between sessions.
The surprising study that showed more inflammation
But then Janessa mentioned another study that caught both of us off guard.
In this one, cold water immersion at 45 to 60 degrees Fahrenheit actually showed a significant increase in inflammatory markers right after getting out, and up to one hour afterward.
Wait… what?
Isn’t cold supposed to decrease inflammation?
This is where physiology gets fun.
When you sit in 55 degree water like we did:
- Your blood vessels constrict.
- Blood is shunted away from the arms and legs toward your vital organs.
- Your body recognizes this as a stressor and activates a fight‑or‑flight response.
When you get out of the cold plunge, your body suddenly needs to re‑warm you:
- Blood vessels open back up.
- Blood flow increases to the skin and muscles.
- You may see a temporary spike in inflammatory markers as part of that response.
So depending on when you measure inflammation (immediately vs 24 hours later) you might see very different numbers.
What this means for real people
If you are using cold plunge purely to “kill inflammation,” the science is not as clear or consistent as Instagram makes it sound.
What we can say with reasonable confidence is:
- Cold water immersion can help some people feel less sore and more recovered the next day.
- There are both pro‑inflammatory and anti‑inflammatory phases to the response.
- We still need larger, longer‑term studies.
In our clinic, we do not present cold plunge as an anti‑inflammatory cure. We see it more as a recovery and resilience tool that can complement good training, adequate sleep, and smart load management.
Mood, Stress, and That Post‑Plunge High
When I drop into the cold plunge, I feel an almost immediate mood shift.
At first, it is pure shock. My breath catches, my heart rate jumps, and my brain says, “Get out.” If I stay, focus on slow breathing, and ride out that first minute, something interesting happens:
- My breathing settles.
- My heart rate gradually slows.
- My brain gets very focused.
- When I get out, I feel clearer and more energized.
That is my personal experience. But what does the research say?
A case report on severe postpartum depression
Janessa talked about a case report of a woman with severe postpartum depression who wanted to get off her medication.
Under medical supervision, she began using regular cold water immersion. Over time, she was able to taper off her medication and maintain her mood with continued cold exposure.
This is one person.
We cannot generalize a single case report to everyone, and this absolutely does not mean cold plunge replaces therapy or medication.
But it raises an important idea: cold exposure may have antidepressant‑like effects for some people.
One hypothesis is that intense stimulation of cold receptors in the skin sends a strong signal to the brain that triggers:
- Release of norepinephrine and other neurotransmitters
- Activation of parts of the brain involved in mood regulation
Some authors have suggested that this may contribute to improved mood, motivation, and even decreased pain sensitivity.
Controlled stress in an overly comfortable world
Janessa made a point in the sauna that really stuck with me.
Most of us live around 70 degrees all the time.
If we are cold, we turn up the heat or put on a jacket. If we are hot, we turn on the AC. We have very little environmental stress in our daily lives.
Instead, our stress is mostly:
- Work stress
- Family and relationship stress
- Financial and social stress
Those stressors are often ongoing and hard to control.
Cold plunge is different. It is a stress you choose:
- You know it will be cold.
- You decide how long you will stay in.
- You know there is a clear end point.
This kind of controlled physical stress can:
- Train your nervous system to handle discomfort.
- Build a sense of mental toughness and confidence.
- Give you a healthy way to practice moving through fight‑or‑flight and back into calm.
For many of my patients who struggle with anxiety, chronic pain, or feeling “stuck,” that experience of “I did something hard and I was okay” can be powerful.
Again, cold plunge is not a stand‑alone treatment for mental health conditions, but it can be one tool in a bigger, professionally guided plan.
Immune System: Can Cold Plunges Help You Get Sick Less Often?
As a parent and a clinician, the idea of getting sick less often is very appealing.
You might have seen posts claiming that cold plunges “boost your immune system” or “prevent colds.” Janessa dug into this, and what she found was interesting, but not simple.
The 29% finding
In one study she reviewed, participants used repeated cold water immersion several times per week for a period of time.
Researchers looked at:
- How often participants got sick
- Certain immune‑related markers in the blood
The headline result Janessa shared in the sauna was this:
> About 29% of the participants showed a long‑term reduction in sickness.
Not “29% fewer colds overall,” but 29% of the people ended up getting sick less often over time.
That means:
- Some people seemed to get a genuine immune benefit.
- Others did not show much difference.
A separate randomized trial on regular cold showers in adults found that those who finished with cold water had a significant reduction in self‑reported sick days from work, even though they did not report fewer total illnesses. In other words, when they did get sick, it seemed to affect their ability to function a bit less.
How might cold exposure influence immunity?
Scientists are still figuring this out, but a few theories include:
- Short, intense cold exposure acts as a hormetic stressor – a small, manageable stress that encourages the body to adapt and become more resilient.
- Activation of the sympathetic nervous system (fight‑or‑flight) may temporarily increase certain immune cells in the bloodstream.
- Repeated exposure could train the immune and nervous systems to respond more efficiently.
In our conversation, I mentioned that when you shock the system, your body may naturally ramp up its protective responses. That fits with what some of these studies are seeing.
But again, this is not guaranteed for everyone, and we do not yet know exactly who is most likely to benefit.
Cold plunge should be viewed as one small piece of a much bigger immunity picture that still depends heavily on:
- Sleep
- Nutrition
- Movement
- Stress management
How Sauna Fits In: Heat, Heart, and Recovery
While cold plunge often steals the spotlight, the sauna we were sitting in matters too.
Our sauna during the episode was at 144 degrees, which is on the moderate side, especially for an infrared sauna.
What happens to your body in that environment?
- Blood vessels dilate, especially near the skin.
- Heart rate increases in a way that is similar to light to moderate exercise.
- You start to sweat, which helps regulate temperature.
Several large observational studies from Finland, where sauna bathing is part of the culture, have found associations between regular sauna use and:
- Lower risk of certain cardiovascular events
- Lower all‑cause mortality
These results are encouraging, but they do not prove that sauna alone causes those benefits. People who use saunas regularly may also have other healthy habits.
From a practical standpoint, in the clinic I see sauna as a way to:
- Promote relaxation and down‑shift the nervous system
- Gently increase circulation
- Warm up stiff joints and muscles before movement
- Pair heat with breath work and mindfulness
When you combine sauna with cold plunge, you are essentially asking your blood vessels to open and close repeatedly. Many people describe this as feeling like a “pump” for the circulatory system.
What It Feels Like: From Teeth Chattering to Calm Focus
If you listen to the episode, you can hear a story playing out in real time.
Janessa gets into the 55 degree plunge and immediately says she feels everything “lock up.” That is a classic first‑minute response:
- Muscles tighten.
- Breathing gets fast and shallow.
- The brain goes into “get me out” mode.
As she stays in and focuses on breathing, you can hear her voice gradually relax. Her sentences get smoother. She even starts reading directly from a study while sitting in the cold.
When it was my turn, my experience was similar.
The first 30 to 60 seconds are the hardest. Then, as my breathing slows, I can feel my heart rate start to come down. By the time I get out, I feel alert and calm at the same time.
One thing many people do not realize is that getting out can feel almost as intense as getting in.
- The air on your wet skin feels extra cold.
- Shivering often kicks in.
- Your body is working hard behind the scenes to normalize your temperature.
Some experts suggest that ending your session on cold and letting your body re‑warm itself may be part of the benefit. That re‑warming period might drive some of the circulatory and metabolic changes we discussed earlier.
Who Might Benefit From Cold Plunge and Sauna?
Here are some of the groups I see potentially benefiting when it is done safely and as part of a bigger plan:
- Active adults who want support with recovery between workouts
- People with high stress who need structured ways to train their nervous system
- Desk workers who feel stiff, foggy, and run‑down
- Patients with chronic pain who are working with us to gently retrain how their nervous system processes sensation
- Adults with mood challenges (alongside appropriate medical and psychological care)
Cold plunge and sauna are not right for everyone.
You should talk with your healthcare provider first, especially if you have:
- Heart disease or a history of heart rhythm problems
- Uncontrolled high blood pressure
- Significant circulation problems
- Peripheral neuropathy or reduced sensation
- Raynaud’s phenomenon
- A history of fainting or severe dizziness
- Are pregnant or may be pregnant
And this one is important: we do not recommend cold plunges for young children.
In the podcast, we joked about putting our kids in the plunge so they would stop bringing home colds from school, but the research is not there, and their bodies respond differently to extreme temperatures.
How Often, How Cold, How Hot? Practical Starting Points
One of the big practical questions we get in the clinic is:
> “How much cold plunge and sauna do I actually need to do?”
Most of the research showing benefits uses:
- Cold water temperatures around 50 to 59 degrees Fahrenheit
- 2 to 3 sessions per week
- A total of about 11 minutes of cold exposure per week, often divided into shorter intervals
For sauna, many of the Finnish studies looked at:
- Temperatures between 150 and 175 degrees Fahrenheit (traditional sauna)
- 2 to 4 sessions per week of 10 to 20 minutes
Our setup in the podcast was:
- Sauna at 144 degrees
- Cold plunge at 55 degrees
We deliberately started fairly moderate, with plans to gradually widen that gap as our bodies adapt.
A gentle starter structure we often recommend in‑clinic
This is not a prescription, just an example of a pattern that many of our patients tolerate well after being cleared by their provider:
- Begin with heat
5 to 10 minutes in the sauna to warm up, relax, and practice slow breathing. - Short cold exposure
30 to 60 seconds in the cold plunge at a moderate temperature like 55 to 59 degrees. - Back to heat
Another 5 to 10 minutes in the sauna, focusing again on breathing and relaxation. - Optional second cold
Another 1 to 2 minutes in the plunge if you feel comfortable.
Many people aim for 2 to 3 cycles like this, 2 to 3 times per week. Others prefer shorter, more frequent exposures.
The most important things are:
- Listen to your body. You should feel challenged, not overwhelmed.
- Never stay in so long that you feel confused, extremely drowsy, or numb.
- Have a plan to get warm and dry afterward.
Remember, the goal is not to win a toughness contest. The goal is to create manageable, repeatable stress that your body and mind adapt to over time.
Safety First: When Cold Plunge or Sauna May Not Be Right
Cold and heat therapies are powerful tools, and like any powerful tool, they require respect.
You should avoid or get specific medical clearance before using cold plunge or sauna if you:
- Have known heart disease, arrhythmias, or a history of cardiac events
- Have uncontrolled high blood pressure
- Have severe peripheral vascular disease
- Have open wounds or skin infections (for shared facilities)
- Are pregnant or immediately postpartum
- Are prone to fainting, seizures, or severe dizziness
- Have conditions that impair your ability to sense temperature
Practical safety tips:
- Do not use cold plunge or sauna alone the first few times.
- Get out immediately if you feel chest pain, severe shortness of breath, or sudden dizziness.
- Move slowly when standing up to avoid lightheadedness.
- Hydrate well before and after, especially when using the sauna.
- Avoid alcohol before or during sessions.
In Europe and many other regions, sauna and cold plunge systems designed for public or clinical use should be CE marked to show they meet safety requirements. At Align Therapy, we use professionally installed equipment and closely supervise how it is used.
How We Integrate Cold and Heat at Align Therapy
In our clinic, cold plunge and sauna are supplements, not the main event.
We start with your goals:
- Do you want to recover faster from workouts?
- Are you trying to manage stress and sleep better?
- Are you living with chronic back pain or scoliosis and looking for safe ways to support your body?
Then we build a plan that centers on:
- Education you can actually use in daily life
- Targeted exercises for your spine, posture, and movement
- Gradual exposure to activity and load
Cold plunge and sauna come in as tools to help:
- Calm or gently challenge your nervous system
- Support recovery between sessions
- Give you a structured way to practice breathing and resilience
If you are curious about how cold plunge and sauna fit into our broader wellness approach, you can learn more here: <a href=”https://info.aligntherapyutah.com/wellness-services”>https://info.aligntherapyutah.com/wellness-services</a>.
Ready to Experience It Yourself?
You do not have to figure all of this out on your own.
If you are between 30 and 60 (or beyond) and you are looking for a way to feel better, move with more confidence, and build real resilience, cold plunge and sauna might be worth exploring as part of a guided plan.
At Align Therapy in Lehi, we walk you through:
- How to start safely
- How to pair heat and cold with movement and breath
- How to listen to your body and progress at a pace that makes sense
If you are ready to try our supervised cold plunge and sauna and see how it feels in your own body, we would love to meet you.
You can Sign up for our cold plunge/sauna membership online or call us, and we will help you take the next step.
This article is for information only, not a substitute for professional advice.
