October 8, 2026 by Haley Hansen, PT, DPT
Steve Kerschke: Got about one minute. Laura, how’s the weather in Denver?
Laura: They say it feels like 12 degrees outside.
Steve Kerschke: So you haven’t been out?
Laura: I canceled my run this morning at 6:30. Thank you.
Steve Kerschke: Well, it feels like the mountains here. We’re getting a blizzard. I think I saw this morning it was going to be 11 inches.
Laura: Oh my gosh.
Steve Kerschke: Oh, nevermind. That changed, thankfully.
Laura: Yeah, it’s not snowing where Dawn is either. I just looked.
Steve Kerschke: It’s not?
Laura: No.
Steve Kerschke: Yeah, Dawn was bummed to miss. All right. Well, I know we have some folks still coming in today, but we’re going to go ahead and get started to stay on time. Welcome to today’s webinar. We are going to be talking about cryotherapy, heat therapy, and red light therapy and wellness and rehabilitation. I have Anna Schaffert, Claire Telin, and Laura. Welcome again as always. And before we jump in, we’ll do a little bit of housekeeping here. Just a quick reminder, those of you who are regular attendees to our webinar, thanks again for joining us. We always love seeing familiar names and appreciate all your feedback and participation. If you’re new to QLI, new to our webinars, we are a post-acute rehab facility based in Omaha, Nebraska. We also have an outpatient telerehab program, which is picking up steam. But in either case, we specialize in traumatic brain injury, spinal cord injury, chronic pain, limb loss, and stroke rehabilitation.
So if those types of injuries, you face those regularly, please think of us. In terms of some housekeeping for your CEUs, as a reminder, these are CCMC only. Those of you who are not CCMC, we apologize, but they are just CCMC only.
We just ask that you stay on the majority of the presentation to just hear the content. There’ll be a one poll question at the end. We will let you know when that pops up and we’ll just need you to answer that. And then upon clicking leave webinar, there will be a job form for you to fill out, and that should happen automatically once you leave the webinar, and you should also then get the CEUs and slides automatically sent to you after you click submit. There are at times issues with that. I will also say I had some issues with it on the front end today, so if we run into some snags at the end, we’ll get you all taken care of. I’ll get it sent out to you, but we should be good to go. Just one final reminder, if you have questions, please use the Q&A.
We will monitor that. Laura primarily will be monitoring that, but we’ll try to get your questions as they come. And if we don’t get it during the webinar, we’ll answer them at the end. So with that, let’s go ahead and get started. We’re going to talk about biohacking. This is actually a term, Claire, I think I learned from you. You’re maybe more hip than I am, but biohacking has gained popularity over the past several years as a way to optimize physical, mental, and emotional wellbeing. And so you can use personalized strategies and innovative practices. What we’re going to talk about today are at least a couple of them, the deliberate heat exposure and deliberate cold exposure have been around for many years. Red light therapy I think is gaining more popularity, so that’ll be a little bit new. But essentially you’re using art and science and the environment to change the biology of your body.
So I guess Claire and Anna, we had a lot of dialogue as to even why we discussed this. What’s your take on why we’re even talking about this today?
Anna Schaffart: Sorry, go ahead, Claire.
Claire Thelen: I was just going to say, I think with wearables and a lot of the information we have from a data standpoint, this is only going to continue to be more popular. So we’re just gaining a lot more insight about our bodies and how to hack that biology. So I think it’s here to stay and it’s not going away. So I think just being early adopters of some of this and understanding how you can utilize it.
Anna Schaffart: Yeah, I think I was going to say too, I mean, we’re always trying to stay on the cutting edge at QLI on just therapies and just seeing what else is out there. All three of us are members of the QLI R&D team, so I think we’re always just exploring what new things are out there, what additional therapies are we missing out on that we can incorporate into our day-to-day when we’re treating patients as well.
Steve Kerschke: Yeah, I think we all have different interests in the three topics today. That’s partly why we chose it, just so you all know. There’s a ton of directions we can go with this in terms of nutrition. Claire talked about wearables and data tracking, sleep tracking, things like that. So there’s way more to this topic of biohacking than we’re hitting on today. These are just three relatively well-known ones that we actually had a vested interest. We also, I think, had some thoughts around how they would immediately apply to our patient population. And so we were interested in looking at the research and determining whether or whether or not to apply it and how do we apply it, to Anna’s point, apply it to our programs at QLI. The other thing I just wanted to reiterate is what we’re going to talk about today and in biohacking generally, they’re rooted in principles of biology, neuroscience, genetics, human physiology.
So there’s very scientific reasons why people do this. There’s also this kind of DIY component and I guess iteration component that if you do any research on this, it’s people really trying to push the limits around what they can do and how they can change their environment and what they can learn from it. Just a little bit of a spoiler, there wasn’t a ton of research, at least that Anna and I found specific to brain injury and spinal cord injury on heat exposure and cold exposure. I think Claire found a little bit more, but I was really surprised that the research just wasn’t there. I think there’s good reason for that probably too, and so we’ll be talking a little bit more about that. Before we go into deliberate heat exposure, which Anna’s going to start with, there’s a few concepts we thought it would be good to review.
You’re going to hear us reference the sympathetic and parasympathetic systems, which are branches of the autonomic nervous system. So as a reminder, this system is really meant to maintain homeostasis or balance within our body. As a reminder, the sympathetic nervous system is in charge of fight or flight, meaning when we are faced with stress and faced with something that we need to have more energy for, the sympathetic system is going to be kicking in. And then the parasympathetic is the system that responds to set things and get things back to equilibrium. So the sympathetic system is activated during stressful, dangerous situations to prepare the body for fight or flight. What you’re going to notice is increase in heart rate, breathing rate, blood flow to the muscles, a decrease in digestion while the parasympathetic system is activated during periods of rest, and it’s usually referred to as the rest and digest response.
What it’s going to do is slow the heart rate, increase digestion, and promote restorative processes. So just to highlight this, the key functions are related to heart rate, blood pressure, breathing, digestion, sexual arousal, urination, and sweating, which we’ll talk about a couple of those today, but those are generally the systems that are going to be activated by the few different strategies that we’re going to talk about.
Steve Kerschke: The other thing that popped up quite a bit in our research, and actually the vagus nerve can be accessed in lots of different ways aside from what we’re going to be talking about today, but we wanted you to understand what the vagus nerve does. So the vagus nerve is often referred to as the wanderer. The reason being is it’s the longest cranial nerve and it’s essentially a communication superhighway. So it extends from the brain down to the majority of the organs.
So if you see the photo here on the left-hand side, as it exits at the brainstem, it’s going to hit the heart, lungs, liver, gallbladder, stomach, spleen, large intestines on down. And so it’s going to be a big part of what we do and essentially controls the body’s rest and relaxation. So it’s very heavily involved in the parasympathetic aspects of our body. And with what we talk about today, it’s going to pop up quite a bit.
Steve Kerschke: The last thing that we wanted to remind you of is heart rate variability. Heart rate variability is one of the ways we can measure our body’s ability to respond to stress. It’s also a way that we can measure our vagal tone and whether or not we have a good amount of vagus activity. And so just if you look at this illustration here, what we’re really looking for is the difference between the R intervals, so this 828, 845.
And what we notice is when heart rate variability is high, that means our sympathetic and parasympathetic systems are working really, really well together. When you don’t see a lot of variability, that means that the sympathetic system is on overdrive. It means we’re not dealing with stress and it’s constantly active. And so what we want to see is high heart rate variability, but it is something that we can measure. So you can see down here this relationship between the sympathetic and sympathetic system. Essentially what is happening is it’s popping up or popping out to either slow our heart rate or increase our heart rate as a response to our environment. So just a few terms to get us grounded here, and like I said, we’ll reference them throughout the presentation. With that, I’m going to turn it over to Anna to talk about deliberate heat exposure.
Anna Schaffart: Perfect. Yeah. So deliberate heat exposure is essentially just exposing ourselves to elevated temperatures, and we can do that in several different methods. So pretty popular and very historical that have been done for a long time is dry sauna and steam sauna, and that’s primarily what I’m going to be talking about today, but there’s other forms of ways we can get deliberate heat exposure through hot tub, hot shower, wearing multiple layers of clothing, and then going for a cardiovascular exercise like jogging. So think like wrestlers trying to drop weight. And then infrared sauna has become much more popular more recently. However, I will note that most do not reach the heat ranges outlined in the literature that I’ll be talking about today for the positive health effects.
So when we are exposed to deliberate heat, there is this kind of catalyst of several different physiological triggers that happen in our body, and really it’s regarding thermoregulation. So we are exposed to heat, our skin temperature rises, and our heat receptors are activated. And so our body is trying to regulate our core temperature to be able to lower our core temperature. And so that is through our sympathetic nervous system that that is triggered. And so that fight or flight system that Steve was mentioning is what occurs when we are exposed to deliberate heat exposure. So there are several different things that happen to our body to be able to try to cool ourselves down. So our heart rate increases, our cardiac output increases, we have vasodilation that occurs at our skin surface, so really that’s increasing blood flow to the surface and allowing heat to dissipate through the skin.
Simultaneously, sweating occurs, which then with that evaporation helps cool our body. So you can kind of read here, there’s several different things that are occurring at once, all with the goal of decreasing our core temperature. Once that occurs and we either remove the deliberate heat or our body cools down, then that parasympathetic response kicks in. So again, as Steve was talking about, our heart rate lowers, our rest and digest occurs, we get blood flow back to our organs so that we can start digesting our food and things of that sort. There are several health benefits to this that are tied to that physiological response that happens when we are exposed to deliberate heat. So some of the most research is central around cardiovascular health. So regular use of sauna reduces the risk of cardiovascular events and stroke that have led to death. That has been found significantly through several different research articles.
One that I want to note, they studied 1,688 participants and investigate the relationship of frequency and duration of sauna use with cardiovascular disease, and they found that the risk of cardiovascular disease mortality decreased linearly with increasing sauna sessions per week with no threshold effect in middle-aged to elderly men. So this is important because as we’ll note a little bit later that cardiovascular health is a huge factor for both individuals who have sustained spinal cord injury and brain injury, but also just the general population, it’s one of the leading causes of death overall. Another improvement or benefit to deliberate heat exposure is improved mood. So the body responds to heat with a release of dinorphins and endorphins. So dinorphins are central around first discomfort and agitation, but biochemically set the stage four endorphins that have enhanced effect on our body. And endorphins are those feel good chemicals.
And then overall, studies have found that the regular use of sauna can decrease cortisol levels as well, enhancing the activation of DNA repair, longevity pathways, and increase the activation of specifically heat stroke proteins, which help monitor and possibly repair protein structures within our cells.
And then the last one I’ll note is improvements in growth hormones. So a lot of people are focused on growth hormone right now. It plays a key role in stimulating muscle growth, strengthening bones, reimpairing tissue and increasing metabolism. So there have been some studies that haven’t found that improved results using sauna. I will note though, we’re going to talk about protocols a little bit later, and the protocol for increasing growth hormone is different. So this one is much more of an infrequent use of sauna using it multiple times in one day, but having large stretches of time in between day-to-day sessions versus some of the other protocols we’ve looked at with cardiovascular health are more on a frequent basis, say two to three times a week.
All right, so we kind of went through all of that. One thing that’s noted on this slide is that acclimatization. So that is one thing that they’ve also found with improvements of repeated deliberate heat exposure is our bodies become more efficient. So our responses to heat, we are more efficient with sweating and cooling ourselves down, so that is another improvement to having repeated exposures to the deliberate heat. All right, so I kind of spoke through all of those benefits.
Anna Schaffart: And then safety considerations. So there’s several that you want to consider when doing this, both for yourself or if you are looking at it for patients or clients. I think one big one is dehydration risk. So a good rule of thumb is to consume 16 ounces of water for every 10 minutes of deliberate heat exposure. This is not recommended also for pregnant women or young children under the age of 16.
Also, just interestingly enough, it can reduce sperm count in men. So for men trying to conceive children, repeated deliberate heat exposure can reduce sperm counts, and it does uptick or rebound when you stop doing saunas or hot baths, but it takes about 45 to 60 days, so being aware of that. And then just a good rule of thumb is always start slow and gradually increase to warmer temps.
Steve Kerschke: All right, let’s talk a little bit about cryotherapy. So cryotherapy is really an umbrella term, and it is essentially the therapeutic technique that involves exposing the body to extremely cold temperatures. So some examples of that are what we’re going to explore most today, deliberate cold exposure, whole body cryotherapy. So if you think of those cryotherapy chambers, we won’t talk about those much today, but that would be another example. There’s local cryotherapy, so think ice packs, cold packs, cold towels, and then cryosurgery, which is more of a dermatological approach, but those are all examples of cryotherapy.
Deliberate Cold Exposure (DCE)
Steve Kerschke: In terms of our focus today, we’re really focusing on deliberate cold exposure as an intentional practice of exposing oneself to cold temperatures. One, just quick note, we aren’t talking about hypothermia, especially with spinal cord injury. There is a decent amount of research out there as to putting someone into an induced hypothermia after a spinal cord injury as soon as possible after a spinal cord injury.
We’re not going to talk about that today. Really what we’re talking about is further on, and even in able-bodied individuals, this exposure to cold. And there’s a handful of different ways to do that using cold water immersion and ice bath. You can even just subject yourself to dipping your face in a bucket or a tub of cold water. Cold shower is something that’s really accessible for this. Swimming in cold water, it’s the finish and Dutch population. It’s very common practice for them to be swimming in cold water. Actually, a lot of the research that pops up is related to cold water swimmers because they could design the studies in a way and position their study in a way to get good data. And then as I mentioned, the cryo chambers. So those are the methods in which you can access this. Similar to what Anna was mentioning, we do go through a specific response to cold.
Steve Kerschke: So the first one is the cold shock response. So this is typically characterized by a gasp once you land in the cold water, followed by hyperventilation, increased heart rate, and then this is also followed by the diving reflex, which we’re going to talk a little bit about next. But essentially, this is a sympathetic nervous system response. So back to the fight or flight response that Anna talked about with the deliberate heat exposure. So what we also see is rapid skin cooling, so peripheral vasoconstriction. This causes the blood to shift to the central part of the body. So we think of core temperature. Everything is going towards the core to retain oxygen, maintain heat. And so with that gas reflex that I mentioned, you’re going to get this hyperventilation response, which in the case of exposure to cold water that might cause drowning, this is one of the main reasons that people drown.
In our situation, we’re deliberately doing this, so this isn’t as much of a risk.
Steve Kerschke: And so essentially you get that shot of adrenaline, much like what Anna mentioned with the immediate heat exposure. So in terms of the diving reflex, so this is kind of the second thing that happens, and it involves a slowing of the heart rate, so bradycardia. So after the heart rate spikes, you get that sympathetic response. Now we’re starting to transition into more of a parasympathetic response where you get slowing of the heart rate, you get constriction of the peripheral blood vessels, and we’re starting to move into this parasympathetic rest and digest situation where the body is really trying to promote and retain oxygen during this time.
Steve Kerschke: So we’ll dive into a few different aspects of this. I already mentioned the cutaneous vasoconstriction, cold-induced phase of dilation, and then shivering and non-shivering thermogenesis, which physiologically has been pretty interesting to learn about. In terms of the vasoconstriction aspect of things, like I mentioned, that’s going to start to happen really immediately. And then after about one or two minutes, you get an associated dilation where the blood vessels dilate and blood is starting to be sent to the extremities. Really, this is a safety response. And so as you get the vasoconstriction in order to prevent against injury like frostbite, things like that, the body’s going to start to send blood back to those extremities to start to maintain some level of homeostasis. Claire and I were just talking about this the other day. It’s actually been interesting to learn more about folks with circulation issues such as Raynaud’s.
Steve Kerschke: There’s some research that shows that the capillary changes in the blood vessel dilation can actually be retrained to potentially help individuals that suffer from that. At the same time, individuals with these types of injuries might need to make some accommodations if they end up doing voluntary cold exposure. For example, it’s pretty common for people to dump into a cold tub and keep their hands out of the water because of the thermoreceptors that are located in our hands, similarly to wear neoprene booties for the same reasons. And so there are things that you can do if you do suffer from some of those challenges. At the same time, there’s some research showing that it could actually benefit you. So that’s kind of what happens first and then subsequently. Then there’s typically two responses, one of them being shivering thermogenesis. And so as mentioned by Anna, the hypothalamus is really the temperature regulator or the temperature control center that starts to send signals to the skeletal muscles, and these muscles respond by rhythmically contracting, essentially shivering, and this produces heat.
So this is our body’s way of starting to produce heat and increase metabolism as a response to the cold. What also happens though is what we call non-shivering thermogenesis. And so this is metabolic heat production that is not associated with muscle activity, and this occurs mainly through metabolism of brown fat. We have three different types of fat. We have white, beige, and brown. Beige and brown are heavily researched when it comes to cold exposure. The reason they’re beige and brown is they’re highly mitochondrial. So there’s a lot of mitochondria in this type of fat, and that is what creates the metabolism. It’s also located around the body. It was initially thought to only be located around the clavicles and in the head and the neck, but what we’re finding is it’s located throughout the body and it’s co-activated alongside shivering. So this next illustration gives you a glimpse of what happens.
So if you look on the left-hand side, this is what happens in the non-shivering aspect of things. So there’s non-shivering, there’s some neurotransmitters that are being affected. What we get is an increase in glucose uptake and therefore insulin sensitivity, which we’re going to talk a little bit more about. At the same time in the skeletal muscle, there’s non-shivering and shivering that happens. And so this metabolic result is something that also takes place there. So this is all kind of happening at the same time all while the body’s trying to retain heat and return to homeostasis.
Steve Kerschke: Some of the benefits. So I’ve already talked a little bit about the metabolism. The metabolism through shivering as well as non-shivering is something that activates norepinephrine and releases directly into the fat cells. This is what facilitates the conversion of white fat into brown fat, and because of that high mitochondrial density, it burns calories along the way. And so in the short term, cold exposure increases metabolism and does cause calorie burn. In a study that looked at this, while they did find that, they didn’t necessarily notice a change in body composition and a decrease in weight. One of the reasons that they did not see that is they didn’t necessarily measure caloric intake. So despite this happening, if caloric intake is not adjusted, you’re not going to see the body composition changes. The other thing that I’ll mention is a lot of the research on this is varied because typically individuals who are doing cold exposure are also doing other things such as exercise and to the biohacking discussion, they’re doing other things to manipulate their body physiologically.
And so some of the research is varied because of that. They can’t necessarily always attribute the results that they found just to cold exposure. So something else to keep note of. The other thing that happens is, Anna mentioned this too, is people start to adapt to cold, especially through overexposure. And so that’s why the protocols that we’re going to talk about later really matter. So they matter depending on what goals you are after. And so we’ll talk a little bit more about that. The other thing related to the metabolic changes is there is an increase in insulin sensitivity, which was initially shown on that previous slide. So this is basically our body’s ability to respond to insulin. And so insulin plays a really key role, as you all know, in regulating blood sugar. And so this facilitates the uptake of glucose, and this allows the body to basically clean itself of glucose and can have really a positive effect potentially on type two diabetes.
And so that insulin sensitivity is a really nice benefit that has been shown in the studies as well. In terms of energy and focus, what ends up happening as a result of that sympathetic response is there’s a significant release in epinephrine, which also is known as adrenaline, as well as norepinephrine or noradrenaline. So this happens in the brain and throughout the body. These make us feel alert and allow us to keep moving. And so that’s also going to come into what time of day do you experience or decide to expose yourself to cold? A lot of the research shows that it’s better earlier on in the day to help with that energy and focus and alertness. If it’s done later in the day, it can affect sleep because essentially you are getting that sympathetic response and then the parasympathetic system has to kick back in in order to get you into that restful state.
So that might be something to consider in terms of timing. As far as mood, there are some pretty significant…
There’s a good amount of information related to effects of stress. So back to that vagal nerve, cold exposure is just one way that the vagal nerve can be impacted. It can also be impacted through singing, meditation, yoga. So there’s lots of ways to impact the vagal nerve, but cold exposure is just one of them. And so that release of dopamine as a result of stimulation of the vagal nerve has a really big impact on one’s mood. Then some information on mental resilience. This is simply around can you come back day to day and subject yourself to deliberate cold exposure? There’s just a mental component to it of being able to just jump right into cold water. Over time, what the research shows is people become adapted to that and our body responds to that. So the mental resilience being tied to that is one thing that we see.
I mentioned the sleep. And then the other thing that we end up seeing is inflammation and muscle soreness, especially the information on this is after athletic performance. So there is research showing that delayed onset muscle soreness is impacted by cold exposure. There’s a timing factor of this too, and then there’s also some negative effects as a result of that parasympathetic and sympathetic response. So something just to keep in mind in terms of that.
Steve Kerschke: All right, so some safety considerations, certainly the risk of hypothermia. This is going to end up happening based on how long you’re in the water. Similar to what you see in the heat exposure, cardiorespiratory issues are a potential side effect. So that hyperventilation, increased heart rate and blood pressure and cardiac arrest certainly are potential considerations. And then any freezing or non-freezing cold injuries such as frostbite and then cell death. What we also found was that extended exposure to heat and cold can cause cell death, which starts to pop up in the protocols that we are going to mention. And then the start slow gradually decrease to colder temperatures, very similar to the heat exposure. What most of the research is showing is that it’s going to give you some specific temperatures to consider, but at the end of the day, it really comes down to what can you tolerate?
And then if you do it over time, what is your body telling you and how do you make some of those decisions? So the takeaway is don’t make it too complex in terms of what you’re choosing as far as your temperatures.
Steve Kerschke: All right, Anna and I are going to tackle this next section together, but there is what’s called the soeberg principle. And so this is the idea around the order at which you might do heat exposure and cold exposure. You can certainly do them separately, but the sober principle looks at them together. And so it’s this idea that you can activate the brown fat, which again burns energy through this, but the order at which you do it can cause an extended increase in metabolism. And so what Susanna Soberg says is that doing heat exposure prior to cold exposure maximizes the metabolic benefits because essentially it causes the body to rewarm itself through a more natural physiological process rather than using an external heat, a blanket or something like that.
And so that’s essentially the principle. So Anna, do you want to talk a little bit about the heat exposure? I know you have some specifics around protocols, things like that. You alluded to it in return related to growth hormones. So I’ll let you take that and then I’ll do the cold exposure one.
Anna Schaffart: Yeah, so most of the research behind protocols for heat exposure is a temperature between 80 to 100 degrees Celsius or 176 to 212 degrees Fahrenheit, which initially I was caught a little off guard about that seems very warm, but remembering these are for shorter periods of time. So this is five to 20 minutes per session and doing it two to three times per week, but upwards up to seven times per week. So as noted here for 57 minutes of total time per week. Again, this is for more improvements in what I noted for cardiovascular health, mood benefits, and just overall improved stress response and overall health. If you want to focus more on the growth hormone improvements, then that protocol changes. So that is much more infrequent. That’s once per week or less for multiple 30-minute sessions in a day. And as Steve noted, there’s a lot of research related to going back and forth.
So going from heat to cold, heat to cold, which has been done extensively in Finland and in other European countries. And with the specific growth hormone improvements, they have found that going back and forth uptick, that growth hormone increased in it when you did both the heat and cold exposure.
Steve Kerschke: So in terms of cold exposure, kind of a similar process. The recommendation is to do this over multiple sessions throughout the week, and actually there’s not a ton of benefit above about five minutes per time. The thing that you should consider too though is the temperature of the water. In the cold exposure case of things, there’s research around anywhere between 50 degrees down to about 35 degrees. And so that’s kind of the range that you’re looking at, but essentially the colder the water, the less you need to be in it in order to get the effects that we’ve already discussed. And so in terms of this protocol, if you can get a total of 11 minutes throughout the week in about two to four sessions at one to five minutes per session, you’re going to start to maximize the benefits of cold exposure. And again, the temperatures that you choose for both of these are really based on personal tolerance.
We gave you some of the parameters here, but what I noticed in the research with cold exposure, and I think there’s probably going to be more coming out about this, it doesn’t have to be super cold. It has to just be cold enough to elicit that cold shock response as well as the dive reflex because that’s going to initiate the sympathetic nervous system and then the result in physiological processes as a result. So that was one of my biggest takeaways, even to the point that I alluded to is taking a cold shower and even submersing your face into a bucket of water can elicit those responses. And so as we were… Uh-oh. Did our power just go out?
Anna Schaffart: I can still hear you, Steve. I got flicker of light, but I still got power currently.
Steve Kerschke: Yeah. Presentation team. We were supposed to let the group know that we’re having a giant snowstorm today, so if there’s issues. But I guess what I was saying is it becomes more accessible to people in a wheelchair or who might have a physical disability to be able to access these things. And so I think that was a really nice takeaway.
Anna Schaffart: Yeah, I saw the same thing. I think really the biggest thing is it should be uncomfortable. You want to induce this stress response. So whatever that is for that person, if you’re uncomfortable and maybe have the feeling of wanting to get out, then you’re likely getting some of the benefit. Obviously being mindful of where that temperature is, that it’s in a safe range and that you’re doing it from a safe time perspective, especially if you’re starting early and haven’t done this over time. I think another just anecdotal thing that I thought was kind of interesting is our body temperature changes throughout the day. So there’s certain parameters on when you should do, I know they say to start with hot and end with cold, but in regards to sleep, it actually is better if you do your sauna end of day or heat therapy end of day because your body naturally becomes warmer, your core body temperature becomes warmer end of day and vice versa for cold.
So that’s another thing if you’re doing this for sleep improvements, looking into looking at cold exposure earlier in the day, heat exposure end of day.
Steve Kerschke: Yeah. The other thing just to mention, I didn’t see any research on gender. I think that was just not something I found on the research, but one thing to note is men are generally running about a two degree lower body temperature compared to females. And so some of the research around sleep temperature and ideal sleep temperature, that might be one of the reasons why maybe you and your significant other or spouse have some disagreement around the temperature around your home, whether it not be when you’re sleeping or even throughout the day. So I’m sure there’s going to be more information coming out on gender differences and response to that. There’s actually differences in brown fat too, so there was some information out around that, so more to come on that. All right, we got to get going to red light therapy, but we have a couple more slides on just how does this directly apply to brain and spinal cord injury?
Anna Schaffart: Yeah, so really quickly, I think just noting that both specifically spinal cord injury, but brain injury as well have difficulties with thermoregulation is a common issue. And so being really mindful of that when starting this, that they don’t have the ability to maybe sweat or cool themselves down when you were talking specifically about heat exposure compared to general population. And as Steve noted, there is limited research on the safety of this. I found one article from 1992 that looked at the safety of sauna for tetraplegia and paraplegia subjects, and it found that sauna bathing for up to 15 minutes for tetraplegia and paraplegia within normal body temperature was safe, but there was really small sample sizes. They only used six individuals with tetraplegia and four with paraplegia. So feeling like there needs to be more research done from that aspect to understand is this safe, but a good rule of thumb is starting slow, lower temperatures for heat and less time.
But there is a potential benefit because cardiovascular disease is so prevalent in individuals, especially following spinal cord injury, but also brain injury. Individuals with spinal cord injury are three times more likely to die from a cardiovascular event. And there’s some very clear research that supports the improvements in cardiovascular effects with specifically heat exposure, but also with cold exposure. And so it’s something to consider when we’re looking into this.
Steve Kerschke: Yeah, I think related to that, the study that I found was related to vagal nerve stimulation. And so there’s several studies that just show that the stimulation of the vagus nerve, which by the way, again, can happen in lots of different ways. Early studies, they used electrical stimulation to do it, but there’s lots of different ways to stimulate the vagus nerve. In terms of cold specifically, I think a cold towel, facial submersion, that would be a really accessible and probably safe way to do it with our population. And what it does show is that it does have an impact on neurological protection, improvement of disease prognosis. So again, this was one study that I found, really small subset of people, but they showed some impacts on stroke, Parkinson’s disease, Alzheimer’s disease, and depression. The other one that I didn’t put on here is I did find one study that locally cooled the body above and below the injury of someone with a thoracic spinal cord injury to see how the skin responded.
In both cases, the skin did cool and they noted many of the same physiological effects that we mentioned, although it was different and more normalized above the injury than it was below the injury. So that’s what they found in the study, but I think more local and not so full body exposure is probably the place to go at least to start. And then depending on the situation, I think there’s some opportunity to apply the cold and heat that we discussed.
Anna Schaffart: Yeah, I think the last thing to note to that is just considering accessibility. So that was another thing we ran into with both cold and heat is if someone is utilizing a wheelchair for mobility, how do they access these things? And so that’s another consideration.
Steve Kerschke: Yep. All right, Claire, red light therapy.
Claire Thelen: Sweet. Yeah, we’re going to transition a little bit to talk about red light therapy. So what exactly is red light therapy? It’s a non-invasive treatment that uses low wavelength red or near infrared light to heal the body at a cellular level. So we know that sunlight is therapeutic and different wavelengths of light have different effects in the body. So the most important health benefits that we’re going to see are going to come from that near infrared A and red light, because those are going to penetrate deepest into the tissues. So if we take a look at this, this is the solar spectrum. So we can see on the left-hand side, the UVB, the UVA, those can have really harmful effects on the body. Then we move into the more visible light, and then there is some red light in the visible light, but then it moves into that infrared.
So the NIRA is going to be the most beneficial because again, it penetrates the deepest into the tissues, and then we have the B and the C. So we’ll talk a little bit more about those as well as we move forward and talk about some of the risks involved as well. I should mention that there’s other terms used when talking about red light therapy. One of them is photobiomodulation. This is just kind of an umbrella term that is given to any light source used to treat clinical conditions. So red and near infrared light therapy falls under that. So yeah, go into the next one, Steve.
Claire Thelen: So how does it work exactly? There’s a very scientific way to explain this, but I think just to make this easily digestible for today, kind of going to use an analogy to better understand this. So imagine your body is a big city and your cells are buildings. So inside every building or your cells, there’s a power plant called the mitochondria. These power plants produce energy known as ATP, which keeps everything in your body or the city functioning properly. So if these power plants become damaged due to weather or injury, illness, stress, what have you, your body’s going to struggle to produce enough energy. So this is where red light therapy comes in. When red and near infrared light penetrate the skin, they can travel deep into our cells and recharge the mitochondria. This is going to boost the ATP production, which can lead to faster healing, improve brain function, enhanced muscle recovery, and reduced inflammation.
So essentially, red light therapy helps power up our cells so they can function at their best. So really we’re looking at optimizing the mitochondria for increased production of ATP. So if we look at this on the slide, you can see kind of how the red and near infrared light wavelengths can penetrate so much deeper into the tissues than the other forms of light, which is why it has so many healing properties.
Again, that red light is going to be best for skin and surface healing and the near infrared light. That NIRA is going to penetrate deeper, which is going to be more ideal for brain and spinal cord recovery, which we’ll talk about a little bit more as we move forward.
Claire Thelen: Moving on to some of the physiological effects of red light therapy, now that we can kind of understand how the basic science behind it, this is kind of how it can benefit us. So it boosts cellular energy, so enhanced ATP production for better cell function and repair. It’s going to reduce inflammation and pain, helping with muscle soreness, some of that delayed muscle recovery as well. And other chronic conditions, it’s going to support skin health. That probably is the most popular one that you guys have all seen at this point, kind of a dermatology intervention using that red light.
There’s masks and things like that that are pretty common. Faster healing and recovery, so it’s going to accelerate wound healing, improve circulation. It’s going to enhance blood flow, oxygen delivery, and nutrient absorption, support brain and mental health. It can help with cognitive function, mood, and sleep. It does increase the production of melatonin in the body and then enhancing hair growth. So I’ve seen a lot of helmet type devices specifically for males who have just the male pattern baldness, so that’s becoming a little bit more common as well.
Claire Thelen: So looking at how can the intervention of red light therapy be used with brain injury and spinal cord injury, this is a study that was done at Mass General by Dr. Greg Hipskin, investigating the effects of pulsed transcranial red and infrared light therapy on cognitive function and cerebral blood flow in veterans. So kind of a smaller sample size, so 12 military veterans with chronic mild TBIs. They underwent a six-week course of the pulsed transcranial red near infrared light therapy where LED light treatment was applied directly to the head. There was a specific helmet that was used for this specific study. So some of the key findings that came out of this were cognitive improvements. So all participants showed improvements in 14 out of the 15 neuropsych assessments with significant enhancements in areas such as memory, concentration, and processing speed that increased cerebral blood flow, and then report and symptom reduction.
So one of the other things I thought was kind of cool from this study was there was all the individuals who were a part of it, some gave feedback, and there was a cool success story that involved a veteran who had been struggling with depression and suicidal thoughts. After the red light therapy treatments, he reported that he was able to return to work and became an assistant coach for collegiate sports. So just kind of highlights the impact that this had, if not on, I guess, something that we can measure, but more so just on his mood and overall quality of life, which is pretty cool.
Claire Thelen: Another study that was found, I should mention tons of research on the benefits of red light therapy for both TBI and SCI for many other conditions as well, but it wasn’t difficult to find them, I should say. So this one for spinal cord injury was a research team that achieved significant progress in using red light therapy or photobiomodulation to treat SCI. So this one, the researchers determined that delivering the red light at a wavelength of 660 nanometers for one minute daily increased nerve cell viability by 45% over five days. So out of this study came the potential for building an implantable device to deliver the red light therapy to the specific area. I believe it’s Medtronic that’s kind of funding this and building this, but this I believe was back in May of 2024, so they’ve already moved along with this. So I think this is just one example of what we’re going to see down the road as far as alternative treatments for spinal cord and TBI.
Red Light Therapy Benefits in Brain and Spinal Cord Injury
Claire Thelen: So again, what are some of the benefits for the population that we work with and treat most often? Reducing inflammation, it’s going to help decrease swelling and neuroinflammation. It’s going to support cellular repair, so enhance the ATP production to aid nerve healing, improves the blood flow and the oxygenation. It’s going to boost that circulation to support recovery, protects against secondary damage, so reduces the oxidative stress and cell death, enhances neuroplasticity. So it may promote nerve regeneration, supporting cognitive and motor function, helps with memory focus, coordination and movement, and it may reduce pain and spasticity, so can alleviate neuropathic pain and muscle stiffness. So overall, it’s showing really good promise, and there’s very few risks involved in using this intervention, which we’ll talk about next.
Claire Thelen: So how do you use this safely and effectively? Choosing the right light is going to be really important. What are you targeting?
Again, red light best for skin and surface healing. Near infrared light is going to penetrate deeper, ideal for brain and spinal cord injury. The right device, there’s so many devices out there, and I should mention that they’re not all made equally. So on the market, there’s not a ton of regulation at this point, so some of the devices may not deliver the correct wavelengths or intensities needed for therapeutic benefits, so choosing a reputable brand is really crucial. I think there’s going to be more emerging research about this and just how many EMTs are the negative effects of a low cost or low budget device. So I think just making sure that you are looking at the research prior to purchasing one. Following the proper treatment guidelines, so session length, 10 to 20 minutes, three to five times. You want to avoid overstimulation. So that is going to be one of the risks is overuse and overexposure.
So it could overstimulate your cells leading to diminished results or mild discomfort. Again, we already talked about this one, but targeting that right area for whatever you’re trying to heal. And then kind of like Steve and Anna mentioned, but in addition to doing the red light therapy, it’s supporting the healing with your other lifestyle habits as well. So this is going to be the most beneficial when done in conjunction with exercise, a healthy diet, and good sleep.
Some of the other risks that come with this are going to be, you’re going to want to take into consideration medication. So if you’re on a retinol, retinoid, antibiotic, this could cause skin sensitivity, may resulting in rash. Burns are maybe a little more unlikely, but I think always consult a healthcare provider or look at the manufacturing instructions prior to using just to ensure that you’re not exposing yourself to putting yourself in harm’s way. So other than that, really not a ton of risks involved. They just talk a lot about consistency is key, so wanting to make sure that you follow routine because you’re really not going to see the benefits of it unless you’re really consistent with utilizing the device. And that’s kind of all I have on Think Red Light Therapy.
Steve Kerschke: All right. Thank you, Claire and Anna. I’m going to launch the poll question and then we’re going to jump into as many questions as we can get through in the time that we have left. So just quick reminder, this is your poll question time. Please answer that. In terms of some Q&A, I’ve answered some of them just via writing. There’s a question about submerging the face and is there literature? Yes. If you send me a direct message, I can email those to you. There are some in the selected resources, which we will include in the slides at the end.
So we already talked about Raynaud’s. Again, you can use it. I would say just use it to your tolerance, choose water that’s not too cold, see how your body responds. Obviously, Raynaud’s is a circulation type of disorder, and so again, there’s some research showing that it can be retrained. At the same time, you’re probably at higher risk for some of those side effects. I have a question around dry cold. There is some research around just being in the cold and going out into the cold weather, and it does elicit a similar physiological response. And so yeah, you’re going to get some of the similar benefits. At the same time, most of the research that I did was on cold water, cold exposure in that regard. And so I’m sure that there’s going to be some differences in extent of the benefits. Anna, I don’t know if you saw anything on that in your search.
Anna Schaffart: Not specifically, no.
Steve Kerschke: Okay. There’s a question on TBI, STI, should cold or heat exposure be doctor ordered? I mean, I don’t necessarily think you need a doctor’s order personally, assuming you’re following some of the protocols that we have outlined, maybe consulting with a professional to help you the first time, but I don’t think you need a specific doctor’s order. That’s just my opinion. Anna, I don’t know what you would say about that.
Anna Schaffart: I would agree. I think it’s just understanding how you react to those different types of temperature. How does an individual’s body thermoregulate? Do they have the ability to sweat and things like that from just general temperature exposure, and then going from there, starting slow, doing less heat or not as cold to start with and gradually increasing.
Steve Kerschke: Totally agree. Question on red light therapy, Claire. By the way, Laura, can you Look through these ones that we’ve already answered and get them cleaned up quick so that we can
Laura: I have.
Steve Kerschke: Okay, thank you. Anything on osteoarthritis that you saw, Claire?
Claire Thelen: Yes. All the research suggests that it helps with any type of osteoarthritis, joint pain, any of those conditions. So yeah.
Steve Kerschke: And then anything that you saw on skin cancer as a diagnosis, contraindications, indications, things like that?
Claire Thelen: So what I saw was used with caution, but because you’re really targeting either the near infrared or the red light, it’s not going to have any of those UVA, UVB, which are the harmful UV light associated. We can get some red light when we go out in the sun, but it’s going to depend on the times of day, the conditions outside. So you’re exposed to both when you’re outside. But with this, you’re really only going to be exposed to that direct red light, near infrared light. So use caution, consult your provider, but no concerns other than that.
Steve Kerschke: I had a question on submerging your face in ice water related to weight loss. I didn’t see anything on this. My thought would be, it goes back to, yeah, you’re going to potentially get the physiological benefits. The metabolic benefit of the brown fat could be activated, but I think it’s going to end up coming down to more of your other lifestyle habits, exercise, that sort of thing. And my guess is you’re not going to get the same impact as what you would get if you did full cold water exposure, cold tub, things like that. That’s my take on that one. Claire, there’s some questions on brand of red light. I know you kind of alluded to that, how to choose one. My guess is you would say use those guidelines that you suggested in the presentation. Anything else you would say on that?
Claire Thelen: Yeah, I would say that research is kind of emerging in a little bit. The research is emerging, these products are emerging, so I think it’s something to look at as, I believe I’m saying this right, but the EMTs, so you want to make sure it’s not giving off harmful EMTs. So taking a look at that and then making sure for what you’re targeting that it’s going to be the right intensity of red light. So there’s good information online that maybe we could even, the resources we can maybe even share for some of that, if that makes sense. But it’s not so overly straightforward, but I would say make sure that it’s targeting the correct area, so surface or deeper, depending on the intensity of the red light.
Steve Kerschke: Okay. Coming up on time, I’ll answer one additional one around cold exposure after working out. Anna, you jump in here too, but the stuff that I heard is that if you’re going to do cold exposure, it’s better to wait several hours after because that’s going to really more target the delayed onset of muscle soreness because of the physiological response. Yes, it can have some impact on muscle growth and how your body responds to a workout, especially immediately after. And it probably also goes down to the time that you use it, making sure you’re using a good protocol, things like that. So that would be my response to that. Anna, do you have anything else to add on that one?
Anna Schaffart: Not specifically to cold exposure, but there was a little bit of research behind increasing, if you’re looking to increase your growth hormone with sauna, doing it when you are in a lower insulin period of time. So doing it earlier in the day when you haven’t eaten or after several hours of maybe fasting in a semi-faceted state, there’s some better improvements with growth hormone with that.
Steve Kerschke: Okay. All right. Well, we have questions continuing to come through. We appreciate your questions. Sorry we didn’t get to all of them. I’ll go back through. If there’s names tied to the questions, we’ll try to reach out to you directly. As I mentioned, resources are included. You’ll get a presentation, slides and CEUs upon filling out your feedback for us. Here’s how to get a hold of us. You can text us, call, you can call me. I didn’t offer out Claire and Anna’s cell phones. I’m sure they’d give you that too, but give us a call, reach out. If we didn’t answer your questions during the presentation, we’d definitely be glad to try to do it outside of this. And so with that, appreciate everyone’s time. Anna, Claire, thanks for all your hard work on this. We hope you all found it valuable.
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