I’m so excited to bring you this wonderful interview with Mr. Chu Zhu. He is the founder of a company called Somnus Lab, and they make an amazing mattress cooling sleep system to help you regulate your body temperature during sleep.

Chu is a scientifically sophisticated guest who explains some fascinating aspects of circadian rhythm and the hormonal processes governing sleep, including the role of the suprachiasmatic nucleus—the “light control tower” in the brain—and the buildup of adenosine that creates sleep pressure. We talk about why outdoor light is such a powerful signal for your body clock, why indoor lighting doesn’t come close to matching it, and how caffeine masks the buildup of adenosine rather than eliminating your need for sleep.

We then get into the surprising role of body temperature. You need to cool down to fall asleep, stay cool to stay asleep, and warm up to wake up. Chu explains the surprising reason a warm shower before bed can actually help lower your core temperature, why getting too cold can backfire, and why temperature regulation becomes increasingly challenging as we age.

I’ve also been beta testing the Somnus system myself, so we talk about how it can automatically regulate the temperature of your mattress throughout the night, customize each side of the bed, and track sleep without requiring you to wear a device. And if you’re someone who loves your sleep-tracking data, we have an important conversation about why more data isn’t necessarily better.

This episode will make you think differently about what you’re doing to get better sleep: we get into the technology, but also the general behaviors that can help us get things right—including the effects of caffeine and alcohol, how sensitive the body is, and how sometimes we can simply get out of the way. It’s a great reminder that getting better sleep and better health may be less complicated than we think.

TIMESTAMPS:

Chu discovered some surprising things when he got in to the sleep system technology research. [04:40]

Circadian rhythm is very important in regulating how we use sleeping time. [05:49]

The hypothalamus is the control center of the brain that receives the light and dark cycles governing our sleep cycles.  [07:33]

Caffeine is able to take the spot of the brain’s receptor that is supposed to take in adensoine to tell you if you are tired. [08:30]

If we look at the evolutionary timelline, we see how the sunset and sunrise used to determine our sleep patterns, whereas now we have the lights and screens that don’t allow these mechanisms to work naturally. [11:23]

Also the access to processed foods and sugars, the empty calories are causing problems nowadays. The difference between direct sunlight and the indoor blue light we are exposed to also makes a big difference. [12:16]

Every system in human body has a mechanism to pull it one way and the other way to push it so that you basically have a two-directional regulation system almost in every aspect. [16:35]

So the important thing to do in the morning is awaken naturally near sunrise and get some direct esxposure to light, and then know that in the evening is where most of the problems happen. [17:35]

Wearing blue screening glasses during the day is completely wrong. [19:16]

Body temperature and environmental temperature are very important parts of the ability to fall asleep. [21:23]

You need to cool down to fall asleep and you need to stay cool to stay asleep. You need to warm up to wake up. [23:31]

Take a warm shower which allows the body temperature to drop and then bed covers or pajamas keep your skin at a comfortable temperature, but it is really important to have the room or the mattress temperature promoting a drop in body temp. [28:13]

There are four sleep stages: preparation to sleep, deep sleep, then REM sleep and waking up stage. [32:37]

How do you determine whether you’re getting these factors dialed in? Is it as simple as waking up and feeling alert and energized? [34:48]

The Somnus sleep system is simply a mattress cover like the protective cover you have on your mattress, that is filled with water that creates a cool sleeping environment. [37:27]

How does this Somnus monitor your sleep so that you have sleep data? [50:07]

LINKS:

• Brad Kearns.com
• Brad Nutrition.com
• Brad’s Shopping Page
• BornToWalkBook.com˜
• B.rad Podcast – All Episodes
• Peluva Five-Toe Minimalist Shoes
• Somnus Labs
• Lux, the measurement of light
• The Sleep Revolution
• Why We Sleep

LISTEN: We appreciate all feedback, and questions for Q&A shows, emailed to podcast@bradventures.com. If you have a moment, please share an episode you like with a quick text message, or leave a review on your podcast app. Thank you!

Check out each of these companies because they are absolutely awesome or they wouldn’t occupy this revered space. Seriously, I won’t promote anything that I don’t absolutely love and use in daily life:

Recover Faster: B.rad Superfuel helps with fat loss, longevity, immune function and athletic performance with a potent combo of grassfed whey protein and creatine. A five-star bestseller on Amazon, or order direct and save! Get 20% OFF your first order with code BRAD20

Strengthen Your Feet: Peluva five-toe minimalist shoes naturally strengthen and realign your feet to perform better, relieve pain, and achieve full functionality. Use code BRADPODCAST for 10% off

Online Education: Immersive learning to transform your diet in 21 days, endurance train the right way, prepare Paleo meals for the whole week, get started the right way the therapeutic cold exposure, and custom-design a morning movement routine.

Somnus sleep system: An advanced, water-based mattress pad that uses intelligent, dual-zone temperature regulation to optimize your micro-climate for deeper, more restorative rest. Use code BRAD for $200 discount on SomnusLab.com

Drink Tmrw: Tmrw is a delicious daily longevity drink with 88 potent, clean ingredients  to support cellular nutrition, gut health and mitochondrial function. Use code BRAD for 25% off your first subscription month + free Welcome Kit AND an additional $10 off.

Clean Your Indoor Air!: The Jaspr Air Scrubber is an ultra high-performance, automatic-sensor unit that will address the often-disregarded health concern of indoor air quality. Save $200 on your unit with code BRAD

Explore B.rad Nutrition, online courses, and my favorite gear at: BradKearns.com/Shop

Enjoying the podcast? Please leave a quick review on Apple Podcasts—it helps more people discover the show. Thanks for your support!

#bradpodcast

TRANSCRIPT:

Brad (00:00):
Welcome to the B.rad podcast, where we explore ways to pursue peak performance with passion throughout life. I’m Brad Kearns, New York Times bestselling author, world number one ranked masters age 60 high jumper and former number three world ranked professional triathlete. You’ll learn how to stay fit, strong, and powerful as you age, transform your diet to lose body fat and increase energy. Sort through hype and misinformation to make simple sustainable lifestyle changes and broaden your perspective beyond a fit body to experience healthy relationships, nonstop personal growth, and ultimately a happy, healthy, long life. Let’s explore beyond shortcuts, hacks, and crushing the competition to laugh. Have fun, appreciate the journey, and not take ourselves too seriously. It’s time to be wrapped. It’s time to B.rad!

Brad (00:51):
Hello, listeners. I’m so excited to bring you this wonderful interview with Mr. Chu Zhu. He is the founder of a company called Somnus Lab, and they make an amazing mattress cooling sleep system to help you regulate your body temperature during sleep.

Brad (01:10):
So we are going big with a very scientifically sophisticated guest that is going to explain things really nicely in practical terms. But it’s really important to understand this stuff deeply, as you’re gonna get some great insights on circadian rhythm function and some of the stuff that I’ve really never heard presented in such a memorable way before, the two aspects going on with the hormonal processes in the body, as well as the governing of light and dark cycles in our body by the suprachiasmatic nucleus and the hypothalamus, the light control tower in the brain. Really fascinating stuff and some great simple takeaways that you’ll implement right away to do things like gently cool the body temperature in the evening to help you get to sleep. I’m so fortunate to have been a beta tester on the early product and talking back and forth with Chu and his team about the various nuances and the amazing technology where they can track your snoring for you, people.

Brad (02:11):
I’m like, how do you do that without having to wear anything? Same with your heart rate, your respiration rate. It comes in a pretty big box, but you take this thing out of the box, you fill up the chambers with water, you get on your little app and you set the temperature of your mattress, the water circulating through your mattress to get yourself the most optimal night of sleep. So it’s really beautiful to be able to customize your sleeping experience, but you’re also gonna learn a tremendous amount about circadian function and how the body falls asleep, stays asleep, and gets energized for a wonderful day from Chu Zhu.

New Speaker (02:46):
Chu, II’m so glad to join you. We had some technical difficulties connecting from across the world, but we have a lot to talk about and I’m so excited to hear about ,not just the amazing journey that led you to develop the incredible Somnus sleep system, but the big picture discussion of the importance of sleep and one’s sleep environment.

Brad (03:14):
So thanks a lot for joining me.

Chu (03:17):
Thank you for having me.

Brad (03:19):
So you’ve had a career in the tech world. Maybe you can give us a brief introduction of how it’s gone and how you kind of got to this point to get so interested the sleep system technology. That would be a good place to start, I think.

Chu (03:35):
Right. Well, I was a trained engineer, both in hardware and software. I’ve been working with quite a few different startups over my career. And I got interested i in sleep mostly because I’m very much into exercise in general, all kinds of sports, especially outdoor sports, everything from ski,ing mountaineering, trail running and all the stuff. So pretty quickly, I started to realize recovery is the main topic that is a little bit neglected, among the three pillars any serious or amateur athletes do that is training, eating and recovery. And among which sleep is pretty much the most important bit of the recovery part, which for a long time is quite underestimated. So for me all of a sudden becomes, I, in my engineering mind, I dig deep, deep down to, you know, what are the objective factors that’s impact to sleep?

Chu (04:27):
There’s so many different things in it. And then I literally read through hundreds of scientific papers trying to find the answers in the neuroscience in the sleep area. So that’s where I began to basically became a bit obsessive about sleep as a topic.

Brad (04:40):
So when you’re getting into all the sleep research, and I know many listeners are familiar with some of the leading books and proponents and some of the big picture insights that we’ve discovered, like you really sleep better when the room isn’t totally dark and whatever else you wanna put on the list. But what were some of the surprising things you discovered when you, you did your deep dive into the research?

Chu (05:02):
I think one of the biggest things that most people get wrong is we focus too much on the sleep i- itself. It sounds a bit counterintuitive, but the thing is, the moment, let’s say two minutes before you go to bed, how well you’re gonna sleep tonight is probably determined by a lot of things you did during the day. So I think that’s one of the bigger things. Of course, it’s very obvious thing to do. One of the very obvious things to do is like keep it dark, keep it cool. But I think the most important thing, or even more important thing is probably happening during the day already. I often make an analogy before you go into an exam. Five minutes before that, it won’t change the grade or how well you’re gonna perform in exam. So that’s usually the case. That has a lot to do with how sleep works.

Chu (05:49):
We have two main system regulating our sleep. One thing is called circadian rhythm, regulated by our master clock called supracharismatic nuclear, which is right above our optical chasm. So there, it’s basically a clock that running about 24 hours to 24 and a half hours a cycle every day, regulating our alertness. And then the other part is so-called sleep pressure. Basically, the longer time you keep awake, the more this chemical called adenosine is gonna accumulate, which is what, it’s this important chemical that binds to your receptor in the brain that give you the signal that I’m tired, I’m supposed to go to sleep. So these two forces work together as any other bodies, any other mechanism in human body usually have one pulling, one pushing kind of mechanism works on regulating our sleep. So for that matter, we need to work with the fundamentals that is, how do we work with our circadian rhythm rather than against the circadian rhythm?

Chu (06:49):
So that, that being said, something concretely impacts the circadian rhythm is, for example, light is one of the biggest liver that, or colliborator that actually reset our time every day. That’s the reason why we could adapt to time zone differences. For example, we fly to Europe or United States and the jetback could be adjusted in a fairly quickly manner. So main mechanism behind that is light giving a external collaborator, basically rescheduling our starting time and the sleeping time of the day. So that, those things as an example of there are so many things you are supposed to get it right during the day rather than focusing the sleep only. If I have to find one, that would be the most surprising factor.

Brad (07:33):
Oh my gosh, that is so well said. And I’ve never really heard it presented where you think about these two parallel tracks going. And so just to, to recap, the, the suprachiasmatic nucleus, the SCN, is kind of governing. It’s in the hypothalamus, the control center of the brain. So it’s receiving light from your retina, right? Yeah. And determining, hey, this is how humans have lived for millions of years with the light and dark cycles governing our sleep cycles. So we have that. And then we also have the buildup of the chemical adenosine. And I’m familiar with people talk about how coffee works and coffee is the thing that it blocks the adenosine receptor so that you’re normally would feel sleepy, but now coffee shuts that off to give you a boost of alertness. Is that how that’s going?

Chu (08:30):
Exactly. And you can tell by the name almost. The main reason for that is the molecular structure is very similar between caffeine and adenosine. That’s why caffeine is able to take the spot of the brain’s receptor that is supposed to take in adenosine to tell you if you’re tired. Now, it’s blocked, so nothing is sending there. So you probably have heard something called caffeine crash, meaning if you’ve been taking coffee constantly all the way till midnight, till in the dome, all of a sudden you forgot to continue to have another cup of coffee, then the caffeines are gone and all of a sudden the, the adenosine are still building up in your brain. It just, it doesn’t go to the receptor. All of a sudden it’s flooding into the receptor. You feel the crash at that time. So pretty much you’re spot on on how it works.

Brad (09:18):
So this would be someone who decides to cold turkey, quit their coffee habit, and then they feel horrible because really the coffee has been masking the appropriate buildup of adenosine and they’ve been not getting enough sleep, I suppose.

Chu (09:32):
Yeah, exactly. That’s a super interesting mechanism. Once you know about that, I think you could design your own protocol of how to deal with that. And on the topic of caffeine, I think one thing also very often ignored is the half, so-called half-life of caffeine. It usually runs about four to six hours for normal people. So timing and dosage makes the poison here. So if you have coffee too close to your bedtime, it’s very much gonna disrupt your sleep architecture, right?

Brad (10:04):
So without coffee’s interference, the levels of adenosine will build up over the course of the day and get really high in the evening. I suppose melatonin will come in here too and make us feel authentically sleepy. And that’s the stuff that we can possibly screw up with the coffee habit or perhaps disconnecting from our circadian rhythm on that side too.

Chu (10:32):
Yeah, exactly. So that’s precisely how we are built today. I mean, the other thing is that our living environment and our biology, our DNA are not so compatible in many aspects, right? So take light, for example, again, we’re live, we’re supposed to live brightly outdoor and then sleep at night darkly, but now we’re almost living in a reverse world. We’re too deep during the day and too light during the night. And caffeine and any other stimulants like that, or chemicals, alcohols, caffeines, or screen stimulant as well, we did not, we did not have that before organically, but now everything is introduced to the mix and, uh, we still have the old gene that we, we have. So that’s one of the big discrepancies we have versus our hardware and software system are not as compatible as it could be.

Brad (11:23):
Yeah, it’s kind of funny when we look at evolutionary timeline, we really only have, you know, 150 years or something where we have lively evenings that are fully eliminated. Before that it was, you know, maybe candles and things really wound down – Yeah. And the sun set over the horizon. And if I get this right, once that sun sets, this also triggers all these sleep mechanisms like the buildup of melatonin and adenosine to where we have no problem falling asleep at night from our evolutionary biology. So people that complain of having trouble falling to sleep today, you can kind of trace this back to we’re not giving the, the SCN the proper signals starting with, I suppose, sunrise and getting up and getting out into bright outdoor light.

Chu (12:16):
Absolutely. And we see these similar examples in almost all aspects of life. For example, we have too much access to empty calories, the sugars, the fructose and glucose, all these stuff. We used to not be able to get access to that on a regular basis, so easy, you know, in the processed food, all of the additives added to in it, which is unconsciously taking in too much empty calories quite often. That’s one of the reason why we have so many diabetes, especially type two diabetes nowadays. It’s similar problem. Our genes are not, not built that because we’re supposed to store all the energies possible for the cold winter supposed to come. We, we would just have totally different living environment nowadays, right?

Brad (12:55):
So if one does not get sufficient time outdoors, but they’re in a well-lit workplace and a bright screen is blasting their eyes all day, is this still like insufficient total light exposure for the day because it’s not as strong as outdoor light? Or how does that work if, of course, we’re, we’re lit up all day long in most people’s cases, whether or not it’s outside in real light. Is there a difference between what we call blue light from the screens and from the light sources versus being out in direct light?

Chu (13:31):
That is a very good question. Yeah, the short answer is usually that’s not sufficient because it might seemly, seems very bright indoor, but if you actually take a measurement on that, the so-called lux, which is the one of the unit that, that we measure how light a light is basically. So indoor, if I look at a very bright room, usually you’re gonna get like a few hundred lux. But outdoor, if it’s in the sunny day, we’re, we’re looking at 100,000 lux. Even in the cloudy day, it’s gonna be like 10,000 or ma- many thousands of luxes. So it’s a, a few orders of magnitude and difference in some strength. Sun is just a such powerful light source. It’s the source of the universe or the, the, the life, of course. So many things get it’s easy to get it wrong that, oh, I’m so bright indoor, I must be getting enough of that.

Chu (14:25):
There’s a concept called melanopic EDI, meaning melanopic equivalent daylight illuminas. Essentially, because the light strength, it’s sort of it’s to the square strength, it, it’s, it’s opposite square of the distance that is to your eyes. So same source of light, if you put it so close to your eyes, the melanoscopy will be able to get it sense it much stronger. So the way how we actually perceive the light strength, it has this EDI that we, we’re calculating at least when we’re looking at how much in terms of quantifiable dosage you can, you’re supposed to get for waking out of the brain times time, that is basically the equation that we’re working with.

Brad (15:11):
Yeah, I’m thinking of my son, Jack, who’s testing out the version of the, early version of the Somnus unit. He loves it, and he’s been having trouble falling asleep, a super healthy young guy, but he’s also testing out using one of those really bright SAD lights that to wake up and not only get outdoors, but like really get blasted so that he’s, he’s doing the proper messaging for the SCN in hopes of falling asleep easily that night. But as we’ll get to shortly, the temperature regulation of his bed has been a big help and he’s already noticed improved sleep habits. So iit does seem like there’s a lot of factors at play. I know people get kind of stressed and overwhelmed with all the to-do list for health practices, but we really are talking about, you know, the most important thing on the entire list.

Brad (16:01):
And I think we can put a chart in the show notes that you can find on the internet, but I was shocked to see like they have the light intensity of the various sources and like even a cloudy day is – Yeah. You know, really a powerful message for your SCN, your hypothalamus to say, “Okay, iit’s morning, it’s time to get up.” And that’s like key to kind of get outdoors and start your day with some real light, apparently setting yourself up for those hormone releases later in the evening after the sun sets.

Chu (16:35):
Absolutely. And ithe human body is just a magnific- magnificent system that is, it’s just so many nuances in that. the way it’s been working or after the hundreds of thousands, if not millions of years of evolution, we have so many practical designs of, you know, like I mentioned, every system in human body usually has a mechanism to pull it and the other way to push it so that you basically have a two-directional regulation system almost in every aspect of that. And so light is exactly the same thing as well. Like you mentioned, the morning, you see the light, you properly wake up the brain, you get a cortisols at the right level, you get a body temperature up so that you’re ready to engage with the day. And then you peak during the day and then gradually go down, supposedly at least.

Chu (17:26):
So, so that’s, that’s how, how, how human body functions from a biological, most fundamental point of view, right?

Brad (17:35):
So let’s get some takeaways going. We’ve talked about the important thing to do in the morning is hopefully awaken naturally near sunrise, get some direct exposure to light, and maybe we should switch to the evening time, which is probably where most of the screw-up happens in the form of blasting our eyeballs with artificial light after it gets dark. Again, referencing how powerful the sun is so when the sun sets, it’s a really powerful evolutionary message, and we basically ignore it or override it with not just caffeine during the day, but now we’re talking about light sources, right, in the evening.

Chu (18:20):
Absolutely. I mean, one thing we should definitely avoid is the clinical science, scientific studies, the 460 to 480 nanometers frequency range, blue light-ish, is the range we want to avoid as much as we could at least, like, two hours before you go to bed, because that’s so efficient even at 10 lux of intensity is gonna wake up your brain by suppressing the melatonin.

Brad (18:44):
And let me guess, that range is found in digital screens, phones, televisions, laptops.

Chu (18:52):
Of course. Yeah. I think most of the modern phones, they do have some kind of a night mode, so it looks a bit orange and warmish, which is the way they, at least to some extent, eliminating the blue light frequencies.

Brad (19:05):
So is that stuff legit if you walk around wearing your biohacker orange glasses or set your devices to be a little more mellow in the evening time?

Chu (19:16):
I think that definitely helps. But the other thing I often see people doing wrong in terms of this practice is they wear a blue screening glasses during the day or so, which is completely wrong, because you’re not supposed to block the blue lights in the day. You should get as much as possible during the day – Yeah. So that keeping your brain awakening. Otherwise, if you filter that out, the brain will get completely confused on what is it now? There’s no blue light whatsoever. So here’s the thing, we’re sending so many different signals to our brain by only following certain tips or buying certain gadgets only without understanding how it functions underneath. So we’re literally creating five different conflicting signals to the brain, telling different things, pulling each other away. So that’s why I think it’s so important to understand the fundamental mechanisms behind what are the regulators, what are the livers under, under the sleep mechanism, per se.

Brad (20:14):
Oh my gosh. In your face, biohackers. We’re calling you out right now. And, um, boy, that’s funny because we, we have this goal of maximizing, especially natural light during the day, and easy to mess that up. And then at, at night, you know, being not diligent, especially in the last couple hours. So if, I guess, melatonin is suppressed, you don’t get the sleepiness signal, and then it comes to be 10:00 or 11:00 when you wish you could go to sleep, but hormonally, chemically, you’re, you’re prevented from doing so. Is that, is that what’s happening when people are, frustrated with inability to fall asleep?

Chu (20:54):
I think that’s one of the. It’s a complex issue. Of course, what we’re talking about here is not trying to give any medical diagnosis. So if one has insomnia or similar medical conditions, definitely once you treated doc – by being treated by a doctor. What we’re talking about mostly is if you are generally healthy – Mm. These are the protocols or at least the things you should know for you yourself to help design the how your personal protocol like, right?

Brad (21:23):
Yeah. I know that body temperature and environmental temperature is a big one, so maybe we can push on to that subject which is so near and dear to your heart and – Yeah. Your recent invention. But what’s the science reveal on that as it relates to falling asleep and staying asleep?

Chu (21:42):
Right. Like I mentioned, I actually identified multiple underlying factors that has objective impact on sleep. We pick temperature regulation as the wedge to enter the market because of several reasons. Number one, it is one of the more scientifically grounded theory. I’ll come to that how it works. And then second thing is it’s very perceivable by the users. There are many other things. For example, you can try to impact the brainwave, giving some sound signals and stuff like that. What happens is, like, I’ve been trying pretty much every product you can get in the market. Quite often, if you ask me a few weeks later, how did it work? Did it work well? My, my answer to that would half of the time be, I’m not sure if it actually did any- anything to me or not. Of course, placebo effect is real as well.

Chu (22:37):
Oh, yeah. I might be seeing some, some result because I, I think it works. But coming to temperature, it is so perceivable. After one, two, three nights of using, you know it works, especially for just a hostile give you at least a comfortable environment that is personalized for you to your personal preferences. So that’s essentially why we picked, uh, temperature regulation as a bigger thing to work on at the moment. So coming to the science itself, we mentioned circadian rhythm approximately 24 hours, and along with which, there is a temperature curve. It’s very stable as well. That is basically. You think about what we talked about earlier. Basically, when you wake up, the body temperature gradually rising, and then the peak during the day, and then they gradually drop. And then during, during the deep sleep stage, uh, it goes to lowest temperature.

Chu (23:31):
So usually there is a very stable body temperature minimum that is around somewhere in the, in the dawn time. And then that’s repeating every day. So when it comes to sleep, pretty much there is three key points here. Number one, you need to cool down to fall asleep. Number two, you need to stay cool to stay asleep. Number three, you need to warm up to wake up. So essentially, these are the three key things that we’re working with from a scientific point of view. So give you an example. When we talk about you need to cool down, it means your core body temperature needs to cool down. It doesn’t mean your skin temperature or that. That is not direct translation. Often it’s correlated, but they’re not direct translation. Sometimes it’s giving a revert signal, actually. For example, skin is our biggest sensor to the world of temperature.

Chu (24:25):
Our brain is also a multimodal sort of machine that taking all different sort of signal to, signals to dictate how much am I supposed to set the temperature point for our body right now. We homo sapiens are homeostasis. We need to keep at this rough temperature range. Right. So if you, for example, want to cool down your core, the most efficient way, one of the more efficient ways is to gently warm up a little bit your skin so that it gets a signal that, “Hey, externally is a little bit hot. I’m supposed to cool down.” So that range is really important because you go too far, say you go to the sauna or you stay in the high temperature bath for half an hour, one hour, then it goes beyond the zone, so your core will be heating up.

Chu (25:15):
So that, that’s the thing, it will do the reverse. But if you go too cold, the body is definitely gonna want to warm up then. Yeah. But if it goes to too cold, then the hypothermia will happen. So it’s sort of the range between that. So there is a fantastic research paper called, I think it’s a warm shower effect or something like that. Basically, you take a gentlely warm shower quickly before you go to bed. A, it gives a, some kind of signal to the brain, I need to cool down because it’s a little bit warm outside. B, it opens the, the pores of the skin so that it’s much more efficient in dissipating the heat mechanically as well. So this is a perfect example of once you know how the system works, you could actually design your own protocol on how to deal with that without even having to have any products.

Chu (26:01):
Then of course, as human beings, we’re pretty lazy, at least I will consider myself as lazy. I always want to have something effortlessly happening in the background so that I do not have to think about stuff that often going against my will. You know, things like, “Oh, you should stop looking at your screen after 10:00 able to do the in the rigid form, no screen whatsoever. Yeah. I think probably very few people are able to follow that kind of routine. So that’s what I come back to the product design aspect. We want it to be effortlessly happening in the background improving human health in general. I appreciate that explanation.

Brad (26:42):
I don’t think that’s widely appreciated that taking a warm shower is a way to gently cool the core temperature. And it’s kind of funny, like, uh, that’s what cold punching is all about too. Like therapeutic cold therapy, you get out and your body rewarms because the skin has been exposed to, you know, intense cold. Even for a minute or two minutes, you have a warming energetic effect. And so that would be the undesirable thing to do trying to go to bed, even though we know that we need to cool our body temperature at night. So Ariana Huffington talked about that in her bestselling book, The Sleep Revolution, many years ago. And I know Matthew Walker’s popular book, Why We Sleep, that was one of the great takeaway quotes that I believe he said that body temperature has to drop a couple degrees Fahrenheit in order for us to fall asleep.

Brad (27:37):
And that’s heavy because you can think of there’s so many times in our lives where, you know, we, it was too hot at the campsite or whatever, and you know, we couldn’t fall asleep and we can all reference how sensitive we are to improperly warm environment.

Chu (27:55):
Exactly. So, that’s just something that it’s, it’s so fascinating, the whole human biology thing. So it’s not enough to know one tip, because you need to know the reason behind that tip. That tip might work in one occasion, it will fail in the other occasion. <laugh>

Brad (28:13):
So we take the warm shower. Yeah. We get a slight prompting to have the body temperature drop, and then we get into bed or pajamas. And so I’ve heard that the pajamas or the covers keep your skin at a comfortable temperature, but it’s really important to have, like, the room or the mattress temperature promoting a drop in body temp.

Chu (28:45):
But essentially, if we look at the physics, there is this gradient between the core, the skin, and the environment. I often consider it’s actual gradient. So you need to you want to keep an efficient heat dissipation gradient going along the night, right? So that’s the thing. What, because we constantly produce heat as a living organ, so we just need to have the right amount of dissipation during the entire night of sleep. For younger people, usually we’re much more efficient in thermal regulation, but as we got older, I think the thermal regulation ability, it decreases a little bit. So that’s, uh, also, like, I feel when I was younger, it’s so, it doesn’t matter how hot or cold. I can probably fall asleep, sleep anywhere. Right. Right. My body was just that efficient in heat regulation or thermal regulation. But as, as, as you, as we all ages in general, we, we just lose that capa- capacity, not as strong as when we’re younger, at least.

Chu (29:47):
So in this case, it’s even more important to keep the gradient, at least make sense to your body. So this is the efficient way of dissipation, dissipating heat. So there, we can do it by have air conditioning setting in the room. Cool opening the window or having more even that, that’s when we decided to, hey, this is the way that we could design something more granularly, more accurately, stay closer to your body, what we call a micro sleep environment, you can set it into the granularity that is needed, which is why we work on the mattress topper so that it could actually help you regulate the temperature that you find comfortable with over the night.

Brad (30:27):
So we need to get cool in order to fall asleep. That’s part of the hormonal process and the whole, uh, biology shutting down so that we can nod off. And then number two you said was stay cool. And if you just said that we’re always generating heat, this seems like a possible problem, especially if we got under the covers at whatever time and wanted to, you know, bit warm up or, or feel comfortably warm, but then three hours later, we’re generating all this heat under the, under the big comforter, and then we can possibly have a sleep disturbance because our environment’s all of a sudden too warm.

Chu (31:05):
Right. I mean, exactly like you said. I think the key thing here is to keep that channel of heat is a patient stable, right? So that’s, that’s pretty much where, when we’re talking about room temperature is a part of the, where the heat exchange happens. So, the whole thing here is about keeping the gradient stable. So what happens is one, once you go to sleep, so in the more wearables terms, we have this light sleep, deep sleep, which is generally the category. Yeah. And then, and then you have the REM sleep, that is a rapid eye movement sleep. So these are the generally two big categories of type of sleep that we have. So most of the deep sleep happens in the first half of the night, according to many researchers. So deep sleep is the time that we require the lowest temperature because our cool body temperature will also drop to the lower one.

Chu (31:59):
So that, again, think about the gradient here. So in that case, if you have the, the means, you should, you’re supposed to set the first half of night a little bit lower in temperature than the second half. Second half is still, when your sleep is still low, but slightly higher than the core, so-called deep sleep dominating period of time, basically.

Brad (32:20):
And then as you get closer to wake time, you switch to more REM sleep rather than deep sleep. And then you’re conveying that we wanna actually experience a rise in body temperature in order to prompt waking up and feeling alert.

Chu (32:37):
Right. So in, in general, we divided the sleep process, you might call it, into four stages. One thing is like the so-called preparation for sleep, you’re winding down this entire thing when you’re still awake. And then the first half of night is the deep sleep dominating period. And then the second half of night is the REM sleep dominating period. So there you still keep the temperature relatively low, but a little bit slightly higher than the deep sleep, stage, dominating stage. And then I would say maybe like half an hour, 15 minutes before you wake up, you can gently add more degrees to your temperature curve here. So that’s theoretically, the optimal way of how do you do the regulation, of the night’s sleep.

Brad (33:27):
And this applies to all healthy, living, breathing humans, right? This, you said the temperature gradient of the, of the human is very stable across the 24-hour clock, the gradual decline in temperature from a peak at whatever time of the day. Yeah. Is the peak temperature when we wake up or is it hours afterward or how does that work?

Chu (33:49):
Usually the actual peak temperature, if you’re doing exercise, of course that’s, Oh, sure.

Brad (33:54):
When you do something. Yeah,

Chu (33:55):
Yeah. If you don’t do something, I think it has a fairly stable peak temperature curve during the day when you properly wake up.

Brad (34:05):
And then it’ll just kind of respond to whatever’s going on, your stimulus if you’re outside digging a ditch – Exactly. You’re gonna heat up and all that or, – Yeah. Yeah.

Chu (34:17):
And so basically, there has been researches on if you put the person into a room that is cold, generally, of course, it will induce your body to heat up in the beginning, but if it’s too cold, then your body was gradually dropping temperature. And if you put someone in a room that is dark, it will also induce the body temperature to drop as well. So that’s many of these mechanisms that works together into, to help us to prepare for the sleepiness, per se.

Brad (34:48):
Love it. I suppose these might be obvious questions, but how do you determine whether you’re getting these factors dialed in? Is it as simple as waking up and feeling alert and energized? Do you have much appreciation for the technology that tries to give a scoreboard? I’d love to hear about some of those.

Chu (35:10):
Yeah, this is super interesting question. I’m having, personally having a bit of a mixed feeling on tracking technologies that is prevalent nowadays. I can talk about my, talk about my personal experience. I think the first few months of wearing any wearables, they’re creating immense value for just a few things. The awareness, you all of a sudden became aware of your, oh, there is actually such a thing called sleep architecture and these cafe and alcohol and certain amount of training load is giving you certain type of reactions to the body. So those awareness, I think, is the most important value that these tracking devices are giving us, the wearables are giving us nowadays. Same thing as when I first tried the CGM, the conti- continuous glucose monitor. I all of a sudden understood the correlation between, you know, food and exercise with my blood sugar and the insulin levels and all of that.

Chu (36:07):
Then you, you became much more aware of, okay, I should do more of A and reduce the amount of B. So that kind of thing. Same thing for tracking devices here. So I think they are very, very valuable, but now I do see a trend of people getting a bit too obsessed about the numbers, which is questionable how accurate these numbers are because they’re definitely not ready for medical diagnosis, for example. It’s a really great thing to look at the trend of your whatever number that you’re following, but do not get hang on to the absolute number because they don’t necessarily make sense all the time, right? So that’s, that’s something that I think it’s very important to understand that. And then again, how your body feels is probably, I would definitely value that still value that more than the number itself, because numbers could be wrong, it could be just because you wear it wrong, it doesn’t give you as accurate as it could be.

Chu (37:05):
So your body’s feeling, I would still prioritize as a number one. And then usually, at least to my experiences, they match with the score fairly well. If you feel great and the score is low, I would definitely think I would, I would trust my feeling a bit more. So that’s the thing.

Brad (37:23):
Forget this dumb app. Yeah. Yeah. Yeah,

Chu (37:27):
Exactly. Exactly.

Brad (37:27):
We’ve kind of touched at times on the technology, so I think it would be important for you to explain this amazing invention that I’m, I’m so happy to be one of the early testers of the Somnis sleep system. And maybe some listeners are familiar with mattress cooling technology, but probably not everyone, but it’s really quite something. And what I especially appreciate is for the non-techie type person who just wants to sleep better and do themselves a solid, it’s so incredibly simple. I mean, you get a, a pretty big box, but you, you take the thing out of the box, you, you apply the cover over your mattress just like the mattress covers that keep it from getting dirty. And then you pour water in and all of a sudden you’re, you’re sailing along. So congratulations on amazing invention. And now, you know, let me hear, like, what prompted you to, to get into this and then how does one invent something like this really?

Chu (38:24):
Right. First of all, I think to clarify, I’m not necessarily, I can call the inventor of such a product because it’s been around in a medical environment for decades almost, as far as I know. There are many, uh, post – patients post certain type of surgeries, you more or less need to kept, be kept in the hypoth – close to hypothermia situation to, to be safe. But then of course, those devices are bulky and noisy and probably ugly to our interior taste for most people as well. So essentially what we found is that, okay, now there are technologies that could make it smaller, compact, and quiet, and of course, aesthetically pleasing to put, to be placed in a bedroom. So that’s pretty much where we see, based on the science, this is the thing that we can apply to almost everyone to have the right temperature or thermal regulation setting in your sleep environment.

Chu (39:16):
It, it is very strange sometimes when I think about it. Even in our cars, you can set your left side and the right s – the driver’s side and the passenger side in different temperatures by the different AC settings. But we sleep as the most important environment. We sleep in the same bedroom, same bed, carrying the same sheet. It’s just like. But obviously, most people, married couples sleep together, have very different temperature preferences, right? Like, to our experience, mostly, like, guys runs a little bit hot, girls runs a little bit cold. So it’s almost hard to keep in the same level of both are satisfied. So it’s a constant compromise in our sleep environment because we haven’t managed to digitize or smartize these entire sleep environment just yet. So I, I feel that’s definitely going to happen as one of the next big things that we, like everything else we have done, making our environment more controlled to our favor.

Chu (40:12):
So that’s definitely something that from the bigger background where we came from. Now, it comes to the temperature regulation, and like I mentioned, the science is clear. The technology and engineering bit is kind of a ready. So what we’re doing in other aspects too, is basic translating peer-reviewed solid science into tech-driven products. So temperature regulation being this one. So how it works is also very interesting. Like physically, you have a hundred different ways to heat up stuff, but you only have less than a handful of waves to cool down stuff because it goes against the physics in general. So the way we’re doing it is using water as a medium for basically you heat up and cool down water in the device that we put by the side of the bed, like we mentioned, it’s pretty quired. And then we use a required pump to circulate water into the mattress topper, which is around an inch thick or two to three centimeters thick.

Chu (41:07):
There is a microsilicon tubes embedded inside the mattress topper that we’re creating, and then it gives you the temperature regulation of two independent zones on each side of the bed. So that’s roughly how the temperature regulation is done. And then it has, of course, built in tracking capabilities of the heart rate, HRV, snore detection, movement, and all of those kind of, uh, general biometric datas that we’re supposed to use for both you as a user also to calculate the sleep stagings and stuff. So that’s pretty much what a product does. Temperature regulation and the built-in tracking without having to wear anything if you don’t like. And also then I, hopefully, most people find it aesthetically pleasing being a piece in your bedroom.

Brad (41:58):
Yeah. It looks like a little air purifying machine that’s nice and compact. So the, you, you said microsilicon tubing where the water is running through – Yeah. The mattress topper. You can see the two, it’s like the, you know, the, the, the, the pipe that goes from the machine to the mattress topper or the tubes. And those are kind of thick tubes that carry the water. And then it’s getting dispersed through the entire length of the mattress through these small. It, it’s sort of like invisible. It just looks like a mattress topper, but it’s got that water. And then I guess in the unit is where the, I guess the water is what’s being, what you’re controlling the temperature of the water chamber. And so it’s spitting out pretty cold water if you want. I’m trying to take it all the way to the bottom and see how it’s, see how it feels to jump into.

Brad (42:48):
It great. You pull over, you, you pull open the covers of your bed and you can feel actual cold temperature on the mattress. I don’t know if anyone’s, you know, familiar, if you’ve never, if you’ve never done this, but it, it feels fantastic to jump into a cold bed with the warm cover. So I want everyone to get the right idea, like, oh, I don’t wanna freeze just to sleep well. It’s, it’s extremely pleasant because it’s kind of whatever your, your best term is it for the, the fact that the mattress is cold and stays cold amidst your body’s natural tendency to generate heat is where the magic is. And I know we’ve been talking off recording about how maybe there’s some skeptics that you would love to answer to like, oh, it’s not that important to have a cool mattress, but my practical experience is that it definitely eliminates that common problem of waking up and feeling too warm, especially when, you know, your partner’s emanating heat as well and it just, it’s unpleasant in the middle of the night to realize that you’re a little too warm.

Chu (43:53):
Right. I mean, the science is very clear how it works, but, like that we’re talking about, everyone has a different ability of thermoregulation. So there are people are generally very good at it, so you don’t necessarily need any external device to help that. I think those, definitely those group of people existed. So you probably, as a sleeper who have been sleeping as long as you are alive, so you probably know a little bit about your, your preference of sleep and what are the factors that make you awake in the middle of the night. So I think that’s up for everyone to decide whether it’s a product for you or not. Definitely if there’s, if you don’t purchase any products, follow those protocols we talked about. It’s gonna be definitely helpful too, right? I can share a few stories. Like, there’s one athletes, one of the top athletes of the world that is working with us, he mentioned one description of that I really like.

Chu (44:47):
He says like, “Hmm, before, he always turned the pillow a few times to the colder side because you heat up the pillow after a while.” Ah. So the way he described it, this is almost a feeling like sleeping always on the cold side of the pillow. <laugh> It’s the way he described the feeling. I’m like, “Yeah, this, this is an interest one. I need to steal that co- coat.” And also, I think there’s another way, because the device is pretty versatile. You can use it to your own personal preference. Like, for me, in the wintertime, I wanna get into a warm bed rather than a cold bed. So I do a bit of a warmup and, I jump into the bed warm, and then it, it cools down according to my need. Ah. And it actually falls asleep.

Brad (45:33):
Tricky guy here. Yeah.

Chu (45:36):
<laugh> But in the summertime, I do the opposite. I wanna get into bad cold. So I actually set it at your cooling and, and, then what is needed. And it rise up a little bit temperature when I’m actually going to sleep. So

Brad (45:46):
This – Oh, I’m so glad you mentioned that because I’m thinking of my promotion of, uh, cold therapy and I love my cold tub and I, I go in there for my routine and then I rewarm naturally. And, and listeners, it’s great. I jog down the street and I got a lot of feedback from people in Manitoba, Canada, or Scandinavia saying, “Dude, you know, don’t be talking your California stuff to people that have, you know, if the environment’s already cold, it’s not a big challenge to have that body temperature drop in the winter. And it’s a huge thing in the summer when we’re in hot, steamy environments. So, I never thought about that because I’m just generally thinking I love that cold mattress pretty much year round because I’m in temperate climate, but, that’s really cool. And then I think we should really drill down into that, um, dual zone because it’s so cool.

Brad (46:38):
My wife, Mia Moore, I talk about her on the show where she’s not super, you know, deep into all this stuff, but she’s an incredible sleeper because she doesn’t sleep that much. I think she’s one of those people with the genetics for short sleeping. And when she goes to bed, she just turns into a burrito and wakes up, you know, six and a half or seven and a half hours later where I need my nine hours to nine and a half. But she’s like, “What’s this thing?” And I’m like, “Oh, it’s an amazing mattress, cooling technology.” She’s like, “Yeah, I’m fine. I have no…” She has no complaint and never wakes up. And so if we open up my app, it’s hilarious because her side just says, you know, 75 degrees all the time, and I got my three zones, and I’m experimenting between 54 and 58 to start, and then up to 58, and then the warming setting.

Brad (47:22):
And you really can customize perhaps like, you know, no one’s ever experienced this before in your whole life where you have the control now to really strongly influence body temperature in the most appropriate manner and, experiment every single day if you want tweek in or look at the data that it’s spitting out too.

Chu (47:43):
Exactly. And also, there’s one little feature I wanna mention as well, which is kind of scratching my own itch when we develop that. <laugh> So I, I often run a fairly busy daytime schedule, but I still want to exercise trying to do that almost every day. So sometimes it’s not a choice, but, it became almost like a necessity. The only time I have available is going off for a jog at 10 or 11 PM at night. Wow. And so, but the thing, of course, then I keep it, below zone two intensity usually, zone one, zone two. For me, it’s more like a little bit of exercise. It’s also very meditative when you run in that pace. So regardless, after the exercise, your body’s still heat up. And, so If I didn’t have a device, what I do is I need to find other ways to cool down as efficient quickly

Chu (48:34):
Exactly. And in this case, we have a turbo mode, basically. Try to crank up the power 100%, just ignore the noise level it creates, because I’m consciously choosing that and setting the temperature to the minimum level so I can lie on the bed and being cooling down at the same time. So this is giving me such a big joy that I do not have to stay, you know, in thein outdoor air conditioned room for half an hour for the proper cool down. In this case, I just lie on my bed doing all the bedtime routines and have the turbo running for an hour or 20 minutes in the maximum cooling. So in that case, it’s given me such a great down sort of downtime, ease into the downtime kind of mechanism.

Brad (49:18):
So the turbo mode will quickly cool the mattress to your desired temperature in a compressed time.

Chu (49:26):
Exactly. Normally when we design a device, there is usually something like a impossible triangle. In this case, it will be cooling capacity, the noise, and the, Sorry. In this case, it’s actually a balance between the cooling capacity and the noise. So the noise comes from the fans blowing fast. And so in this case, most of the time we optimize for noise because it’s a sleep environment, as quiet as a possible, it’s our goal while keeping the enough cooling efficiency going. In this case, I just temporarily forget about the noise requirement. I go all in with the maximum output for that maximum cooling efficiency.

Brad (50:07):
It’s also quite pleasant white noise, especially if you’re in a noisy environment. So it might be a, it might be a, a perk that you can crank the thing up to, to have the, the turbo mode noise. Yeah. I think it’s great. Yeah. Well, the, the thing you mentioned about getting the readouts, the data, without having to wear a device, how does it know <laugh> if you were snoring or your sleep stats?

Chu (50:38):
Mm. So,

Brad (50:39):
It’s got a small camera in it watching everything you do. No.

Chu (50:43):
No, it does not. <laugh> No, the thing is we actually spend a lot of time and efforts designing for privacy. In this case, we do know this is a very, very, you know, it’s a privacy environment that we’re designing for. So in the very beginning now, we only have a. It’s not even a microphone. It’s a pickup. It’s a sound pickup device that we, it, it’s able to do two things. One, detect the type of sound, which is sorry, that has very specific sound signature that we could be able to detect. And then also the intensity of that. So basically, we only keep those two information. There is a snore or not, and how intense it is. Uh, we don’t save any files for that matter. And in fact, even in the next generation sensor we’re designing, we’ll be able to detect more sound signatures in your sleep environment exactly the same way, only know what type of sound it is and also how intense it is.

Chu (51:38):
Then, we do not save any files.

Brad (51:40):
Yeah. Uh, and what else is it, uh, the other data is, is it also giving you in the morning or whenever you wanna look at it?

Chu (51:48):
Yeah. So basically, the rest of that is fairly similar to the normal PPG based wearables that, that is heart rate, heart rate and HRV, respiratory rate. And so basically in those categories, and then in the morning, it’s gonna give you the, all those breakdown metrics, but also the sleep stagings, like what we have had in Apple Watch or anything, or a move that you have this much of deep sleep, light sleep, REM sleep, and then there’s also a score we try to give users. One thing we try not to do, uh, in our product design is not to play fear on users, you know, to fearing psychologics. We want to incentivize user from a more positive sentiment when it’s possible. Rather than saying, “Hey, you have owed this much debt,” we’ll say, “Hey, you did a good job today and keep on doing that.” So that’s at least our way try to, if it’s possible, to reduce the anxiety level of the users in the world that is already high stress.

Chu (52:55):
So many esoter – aesthetics.

Brad (52:57):
I don’t wanna hear I’m doing bad again from something else. Yeah. Yeah. Um –

Chu (53:00):
Yeah, but it’s to really, to, to a large extent. Some of my friends, I see the behavior, they will just take down their devices overnight because they know it’s gonna be a bad night of sleep and they work late tonight because they don’t wanna see the red circle that they have to tell me – Yeah. You are sleeping bad. Yes, I already knew that. Thank you. <laugh>

Brad (53:17):
They had, they had too much to drink, so they left the device somewhere else, yeah. Yeah. But how, if you’re not wearing anything on your body, how is it, how is it determining, like, heart rate and, and, and those things?

Chu (53:29):
Right. So we have a thing called the pieto sensor, which is a pressure sensor or type of pressure sensor. So it’s able to detect the vibrating differences between the two heartbeats. So we can get 99.9% accuracy of your, uh, heartbeat. So that’s basically one of the raw data is coming from this piece of sensor called a BCG. And then also the ribcage expanding, contracting, that’s the way we tell. It’s also create different type of, uh, pressure to the sensor, so we can tell the respiratory rate. So basically, that’s the main sensor. It’s working to get all this data.

Brad (54:12):
Oh my gosh, that’s just incredible. And I’m, I’m mostly appreciating the, the cool temperature of the mattress. I’m gonna have to, gonna have to play some more with, with all that data, but you’ve put out a cool product. I think people can learn more at, is it somnuslab.com?

Chu (54:35):
Yeah, Somnuslab.com. S-O-M-N-U-S lab.com.

Brad (54:39):
Okay. So people interested should go to the website, read he great information there and the great videos, and then sign up for updates with email. We’ll get them a nice discount, listeners of the BRAD podcast that are used to that with a code. I think the code will be Brad. Hopefully it’s not taken, but I’ll update you guys more when this thing’s ready. But I’m so fortunate to be able to beta test this unit and really excited about. Boy, I mean, when you think of the people that struggle with sleep and the impact of that on everyday life, this could be really transformative to have people waking up feeling, feeling rested, and then perhaps more energetic to get, you know, outdoor exercise and sun exposure and thing that’s continue to feed and build to better habits, which right now I think, I don’t know about you, but when we slip a little and we start to get off track, it’s easy to get more off track with healthy lifestyle habits because you don’t have the energy to adhere anymore.

Brad (55:42):
So this could really be a boost to turn things around for people that are struggling.

Chu (55:47):
Absolutely.

Brad (55:49):
Chu, thanks for spending the time with us. I think we have a great explanation of not just the technology at hand, but the general behaviors to get things right, and understanding the effects of things like caffeine and alcohol, and how sensitive the body is, and stuff that we can maybe get out of the way to have a simplified approach to getting better sleep, better health.

Chu (56:10):
Absolutely. Thank you for having me. It’s a fun discussion I’ve had.

Brad (56:14):
Thanks for listening, watching it, everybody. Thank you so much for listening to the B.rad Podcast. We appreciate all feedback and suggestions. Email podcast@bradventures.com and visit bradkearns.com to download five free eBooks and learn some great long cuts to a longer life, how to optimize testosterone naturally, become a dark chocolate connoisseur, and transition to a barefoot and minimalist shoe lifestyle.