Shoshana's Summer Playlist (1/5): How to stop feeling tired all the time with Dr. Alexandra Crosswell

0:02Hi, it's Shoshana and welcome to my summer playlist. This summer we're spending time with an idea that I keep coming back to in health. The mind and body are always in conversation. And sometimes that conversation is quiet. Sometimes we notice it right away in our stress, our sleep, our digestion, our attention, or the way that loneliness can settle into the body. So I pulled five talks from the Ted Health Archive that helped me think about that connection a little differently. You'll hear from Alexandra Crosswell on deep rest. Dr. Vivek Murthy on loneliness. Dr. Zika Manuel on quality of life.

0:40Megan Rossi on the gut-brain connection. And Dr. Sasha Hamdani on attention. These are conversations that I really loved having and ones that I found myself thinking about long after they ended. And I hope they stay with you too. This is TED Health, a podcast from TED, and I'm your host, Dr. Shoshana Ungerleiter. Lately, I feel like I've just been tired. And it's not just me. I've been reflecting on how tired so many of us feel all the time, even in those moments when we're technically resting. We'll get through the workday, collapse on the couch, scroll for a while, and then go to bed. But even if we sleep the recommended seven to nine hours, we still wake up feeling depleted.

1:28For me, the best way to describe it is I feel like my body never fully powers down. And I didn't really know why. So I went looking for answers. And that brings me to today's interview with Dr. Alexandra Crosswell. Alexandra is a psychologist and scientist who spent decades studying the mind-body connection. She's trained at Duke, UCLA, and UCSF, and she was on faculty at the UCSF School of Medicine. In 2022, she left academia to bring science-backed tools into improving people's workplaces and daily lives. And what I wanted to really get into today is the concept of deep rest. Deep rest is more than relaxation.

2:13It's a coordinated shift across the nervous system, endocrine system, and the immune system toward an internal sense of safety and sufficiency. And when we're having a hard time accessing that state, it's often because our systems are stuck in stress. Your body isn't getting a clear signal that, hey, you're okay, you're safe. In our conversation, Dr. Crosswell and I dive deep into deep rest. We talk about how chronic stress keeps us from truly relaxing and how it's impacting our bodies over time. She also explains why recovery matters as much as effort and how people can practice small, realistic, off-switch moments in the middle of busy days.

2:57After the interview, stick around for a TED-Ed lesson that can help you get your best rest by answering a surprisingly practical question. What is the best position to sleep in? It breaks down how sleep posture can affect alignment, breathing, reflux, and snoring, and why the right answer depends on your body and your health. That's all coming up after a quick break to hear from our sponsors.

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5:53now I want to welcome Dr. Alexandra Crosswell to the show thank you so much for being here it's a real gift to have you oh thanks so much for the invitation I'm excited to be here you've spent decades studying the mind-body connection and you've worked in academia and now in the corporate world so when you look across that arc why do you think modern life leaves so many people just feeling exhausted? Yes, that's the ultimate question because I think so many of us are just feeling the weight of living in this modern time. There are so many demands that are placed on us, all of us, for various reasons.

6:30And I think that this exhaustion that we feel can really be explained at a biological and cellular level, that really the demands of the world that are placed on us are deeply exhausting to ourselves. And that's because we're remaining in a level of moderate threat arousal, we call it, for much of the day. We have so much that we're responding to constantly in modern life that our system is in this kind of activated, vigilant state for many, if not all, the hours of the day. That is so fascinating. So Alexandra, you describe deep rest as a coordinated shift toward safety signaling. What does the body do differently when it believes at a biological level that it is safe?

7:20That's really the fundamental piece here. So thank you for saying it so eloquently. When we are responding every day to just the demands of life, whether it's a phone call or it's a meeting or it's commuting to work or taking care of your kids, our bodies spend a lot of cellular energy doing that and remaining in that state is very energetically costly and when i say energetically costly i really mean down to the level of the energy in the mitochondria the powerhouse of the cells we have to have our heart rate up we have to be looking around and seeing what's happening or driving our car and oftentimes our bodies interpreting the world around us in a way in which it's trying to decide, am I safe or am I unsafe?

8:06Is there something I need to attend to in my environment or can I relax? It is very deeply depleting for us to be operating in modern life in a vigilant state. And of course, I think most of us in modern life say we're not very relaxed often. And that's because our bodies are constantly looking for cues of threat. And that's a very evolutionarily good thing. We want to constantly be monitoring whether there's something we need to be responding to. Where this gets tricky is that's very energetically depleting because we have to be spending our energy increasing our heart rate, increasing our blood pressure, so that there's oxygen and nutrients going to our brain in our muscles and spending our cognitive thought processes dealing with what's in front of us.

8:56So the opposite of that is when our bodies are able to perceive safety. So instead of perceiving threat, if our bodies are able to perceive that we're safe psychologically, physically, and socially, then our cellular energy can actually be shifted and moved to being able to do the reparative work that our cells need. And so deep rest is a physiological state in which energy can be shifted within the cell to doing the reparative and restorative work of taking care of our bodies. So interesting. I have been trying to kind of tap into that personally lately and recognizing where I feel like what are the ways that it comes up in my body when I feel even a perceived threat.

9:48And so it's something that many of us, I think, even have a hard time tapping into. And the idea of safety as something that the body registers, not just the mind, is really interesting. And it also makes stress feel more nuanced than that simple fight or flight story that many of us were taught. So I know stress can be acute or chronic, and it can show up certainly in our thoughts and our emotions, but also our physiology. So how does deep rest fit into that bigger picture? And why does that matter over time? Yes. So stress is a nuanced word because there's so many different types of stress we can experience.

10:24And as you described, there is something called acute stress, which actually is a very normal biological response to a demand that's placed in front of us. So if you have a big presentation, let's say at work, or you're running late to an appointment, and you feel what's called the acute stress response kick up in your body. So maybe your hands get clammy, and your heart rate picks up. That's a really good response. It's your body activating its resources to be able to actually get the thing done that needs to be done. And our bodies are really well adapted to be able to do that, to be able to have this kind of quick physiological reaction that activates the HPA access, the nervous system, the immune system, all these systems get activated.

11:06And then once that stressor is gone, our bodies can settle. So once you make it to the doctor's appointment on time and you're sitting in the waiting room, your body can recover it and settle back down to a baseline state. And that's good. We want our bodies to respond and react that way. We also want our bodies to be able to do a really good job of recovering quickly when that stressor is over. What we see from decades now of scientific research in the stress science field is that it's the constant level of chronic stress where our bodies are in that heightened stress arousal state with no chances for recovery.

11:44That is the kind of stress that's toxic that we know leads to increased risk of all kinds of diseases from cardiovascular disease to dementia. There's a lot of very strong evidence now showing that it's really chronic stress that wears and tears down our biological systems, leading to not just psychological damage, but really to physical damage as well. I imagine many people listening recognize fight or flight, but they may not be able to recognize just being a little bit on all day long, that chronic stress that's problematic. What are the most common signs that somebody is stuck in that low-grade stress state, even if they think they're coping fine, which so many of us are like, oh, I can handle this.

12:31I would say that the number one signal is going to be if you're ending each day really depleted and exhausted. If you're getting in bed and you're like, oh my God, what a day. I'm exhausted. That's not a good sign. That means your energy reserves. If you think of your energy like a bucket, which it is in a cell, energy is finite. That really means that you went to the very bottom of the bucket. The other sign is if you have a hard time falling asleep. So if you're laying in bed and you're exhausted and you just want to go to sleep, but your mind is racing. It has that arousal where you can't kind of shut it down.

13:10That could be a signal that you've spent so much of the day in that sympathetically aroused state that your body is having a really hard time coming back down into that more neutral zone of parasympathetic dominance where your body can actually relax and settle into sleep. So those, I would say, are the top two signs that you've been operating at too heightened of a state throughout the day. And certainly, I would say coping isn't the same thing as recovering, right? And yet for many people, the stressors that they're carrying aren't optional. So we know folks live with stressors that are structural, including financial strain, discrimination, unsafe neighborhoods, caregiving responsibilities.

13:55So how do you hold the balance between individual tools for deep rest and the social conditions that keep nervous systems on high alert? Yes, I think you are naming what I see as the biggest kind of miss from the wellness industry in stress and resilience and recovery topics. And that is that we so often are told that being stressed or coping with stress is an individual level problem, that you're just not doing something right. You're not breathing right. You're not meditating enough. You're not cold plunging at the right time. and the reality is that so much of the things that are stressful in our lives are really outside of our control whether that's circumstances of our lives or often the systems in which we live in are really putting a pressure i like to call it the squeeze it's like we feel the squeeze of all of the pressures that are placed on us and everybody's are a little bit different from what those pressures are.

15:01And what our goal should be as individuals is to really understand what's happening to us, just who we are as human beings and how our bodies, all of us as humans, are responding in very predictable ways. That we're responding with this heightened arousal state. We're perceiving threats around us all the time. And that's not an individual failure. That's just the reality of how our bodies respond. And when we can see it that way, in that more neutral zone, we can then decide, what are we going to do about that? How am I going to set myself up, given my circumstances? How can I take agency and figure out what I can do to help my nervous system find times of recovery, find times of connection with other people?

15:53and what actions can I take given my circumstance that are actually gonna lead to restoration and hopefully to some levels of peace. I just wanna say thank you for honoring both those realities, the personal and the systemic, especially in this moment in time. And I wanna return to a phrase that you use that feels both practical and also really profound. And that is that you talk about present moment sufficiency, The idea that right now, in this moment, we have what we need. How do you help someone access that mindset when their life is genuinely demanding and not easily changeable? One of the things that the human brain does really well is what I like to call future tripping.

16:40Thinking about the future and getting caught up in what might happen. And then wasting a lot of our precious energy on trying to figure out how to deal with that. when god that's what i do all day yeah the future tripping right so i'm really good at it as humans and it can help us in a lot of ways because we know how to prepare we know what's a plan for and it can also harm us in that we have to realize that we only have a certain amount of cognitive space and of cellular energy and so when we're spending that cognitive bandwidth and energetic bandwidth on the future, we are utilizing extra energy that could be conserved to remain energetic for the rest of the day.

17:29And so what we want to do when we're feeling overwhelmed, when we're feeling like all the demands are being placed on us at once, to just take a moment and say, but for right now, I'm actually okay. I'm actually not in danger. My body might be acting like I am or acting like a big threat is coming. But actually right here in this moment, I'm okay. I am safe. And there's a lot of practices to help you with that, whether it's taking one big deep inhale and exhale, putting your hand on your body to kind of bring your cognitive awareness back to your physical body and realize, oh wait, I'm here in this body in this moment, sitting on this seat, touching my sweater, I'm okay right now.

18:18And if the reality, which it can be for some people, is that they're actually not okay right now in this moment, whether that's an abusive relationship or an unsafe environment, toxic workplace, by doing that check-in for that moment, it will give you the presence, the clarity, the nervous system regulation to then thoughtfully decide what is the right next action. If I'm truly not okay, what in this moment is the next singular step to make sure I'm moving in the right direction towards safety? We'll be right back with more of my interview after this quick break. Today's episode is sponsored by Kashi.

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20:21I imagine some listeners might still wonder whether this is just another self-care trend, right? When I was first reading about deep rest, it certainly sounded like that. So if someone is skeptical, what is the clearest evidence or real-world explanation that shows what's happening in the body and why it matters for long-term health? We now know from decades of research that the brain is in a stressed state when it's perceiving a threat in our environment. So really, the body's response to stress is really the body's response to a threat in the environment. And this comes from evolutionary times when our bodies developed a way to escape a predator.

21:09So if there is a big lion on the savanna, our bodies learned, okay, activate all systems to be able to escape or fight this predator in some way. Unfortunately, our bodies haven't evolved to realize that the threats that are present in modern life are not physical, most often. they're not a predator in the savannah about to eat us they're psychological and social stressors and yet our bodies respond in that same way of activating all systems to escape our minds do a very particular thing when we're in that threat state they narrow in on how to survive the present moment and they focus on the negative cues around us negative cues of threat and this is really important for us to realize as individuals because that means that when i'm in a workplace or a family dynamic and i am feeling unsafe or i'm feeling that sense of threat our minds go really narrow.

22:19We have a hard time looking around and seeing reality because we're so focused on surviving this moment. And so one of the ways that I would say this is not a wellness trend, this concept of deep breath, is it's really becoming stress literate. It's really about decoding what's happening in your body so that you can then start to say, oh, there's that threat arousal, what can I do to allow my mind to be able to think clearly? Because right now, all I want to do is go quit my job, or I want to divorce my husband, or drive really fast on the road. Or eat a bunch of chocolate cake. Yeah, yeah. Eat some chocolate cake.

22:59Those are totally natural, normal stress responses, right, from that evolutionary time. And so when we can understand that. We can say, oh, okay, how do I actually shift out of that hyper aroused threat state into a state of safety so that then my mind can think clearly and really make the right choice based on that regulated state I've gotten myself into? Yeah, you make such a compelling case that this is not indulgent. It's really biology. And that brings us to recovery, right? Which feels like almost the unsung hero of the stress conversation. And your work really emphasizes that stress is not only about what happens, but about how we appraise and then recover.

23:49What does good recovery look like? I really like to think about recovery in the way athletes think about it, is that it's essential. And if you're an Olympian or you're any of these athletes, they know that good recovery is a key piece of the puzzle around performance. Because you can't be operating at your peak performance at all times. You have to be able to allow your body to spend time healing and processing and integrating all the work that you've done so that next time you're even better than the last time. And so we as individuals need to view ourselves as athletes that not just deserve recovery because we've worked so hard, but really need it at a psychological and physical level.

24:39So recovery can look different for everybody based on your personality, your life circumstances, what you've found works for you. It's striking to me how rarely we celebrate recovery in a culture that glorifies endurance, right? Why do you think recovery is undervalued in our culture? I think it's very historical. It really came from the Industrial Revolution, where we as individual human beings think that we should be operating like machines, working until we go to sleep and then wake up and work again, turn back on. And I think that we really have to expand our understanding of what it means to be a whole healthy person by thinking about all the different aspects and elements of what makes a good life.

25:28It's not just working and sleeping. It's being in meaningful relationships. It's finding purpose and meaning in your work and in your days. It's being a contributing member to your community. and all of these things involve more nuanced levels of being, not just on or off. Yeah, that cultural lens really helps explain why so many people, I think, struggle to access this even when they want to rest. So I want to make this practical for people. What are a few reliable pathways into deep rest and how do you help people find the one that fits them, especially if meditation maybe feel stressful or inaccessible to them.

26:11One of the maybe unsung heroes in psychology is really sensory-based tools. And I talk about this in the Deep Rest paper. There's a lot of ways to regulate the nervous system through sensory-based inputs. And so what are the sensory-based inputs that work for you? Best example might be music. Let's say you get in the car and you kind of feel like maybe something really soothing. Maybe you put on some Enya or some classical music. I do that. I listen to spa music when I drive. People are like, are you going to fall asleep? Right. No, but it probably feels great to you. Right? Yeah. And that's because it's just a natural automatic way that you've developed in order to help regulate your nervous system.

26:59And so that makes a lot of sense that when you're driving and there's a lot going on in the road that you want to feel calm, right? And sometimes Maybe let's say you're going to a party and you're with friends in the car and you say, oh, let's put some pump up music on. That's an upper, like a way to upregulate your nervous system and get yourself excited and to kind of match the energy that you're feeling. So we often intuitively use music as a natural regulator. So that is a great inroads. There's also a lot of other sensory tools you can use. So in your home, creating a warm, soothing environment, dimming the lights and lighting candles is a very kind of traditional and old way to create visual sensory input that feels soothing to your body.

27:42So those are just some tools that the listeners haven't heard of because I think we've all heard, oh, we should be meditating. And it's hard to do that. Thank you for broadening the doorway beyond just meditation. I love meditation. I think it's wonderful. But I also know breathing in particular seems like such a universal entry point. So what is happening physiologically when someone slows their breathing, is really intentional, and how can listeners use a simple breathing practice without turning it into yet another performance goal that they need to check the box of? Yeah, yes, absolutely. Scientifically, taking one long inhale and exhale is biologically the fastest way to activate the parasympathetic nervous system, which is responsible for shutting down the fight or flight response to the sympathetic nervous system.

28:28So one deep inhale and exhale is going to be the best way if you're feeling aroused to help your body settle. What's actually happening when you do that is that just physiologically taking a slow breath is going to slow your heart rate down through body to brain signaling. Your brain is going to interpret the slowed heart rate as safety. We're sort of biohacking in a way, right? We're intentionally slowing that heart rate down so that our mind is interpreting that we are safe, we are okay in this moment right now. I'm curious how this work goes beyond physiology and into meaning. How do meaning, values, or a sense of the sacred connect to deep rest, especially for people who do not identify as religious or spiritual?

29:26Yeah, I got really interested in kind of global spiritual traditions when I was a professor at UCSF. And one of the things I became interested in professionally and personally was what are other cultures and traditions and wisdom traditions saying about this? This is an age old dilemma. How do you deal with suffering? How do you deal with things that are hard in life, often outside of our control? And different cultures and religious and spiritual traditions have really a variety of answers into how do you actually do that. And so with Deep Rest, there's actually many ways in. And finding a cultural fit for you is really a beautiful exploration.

30:15It could be prayer. It could be writing. It could be going to church. It could be going to yoga. It could be playing music. There's some very fascinating research on the power of singing in a choir, the beneficial effects of singing in a choir on your immune system. And so I'm less interested in prescribing a certain meditation type or a certain morning routine and more interested in inviting people to explore what from your background or your current interests feel regulating, feel connecting, feel meaningful to you. And then when you're doing those things, touching into how do I feel? How does my body feel doing this?

31:01If your body feels good in yoga or it feels good in church or it feels good walking in nature, there's a lot of research on forest bathing, being in nature, then we want to do more of that. Your cells and your body are happy in that space. Yeah, I think it's powerful to think of rest not only as a bodily state, but as a way of relating to life. And I'd love to explore how this plays out in shared spaces like the workplace. So when you advise teams or companies, what is one change that leaders can make that really meaningfully increases the odds that their staff can recover instead of staying chronically activated?

31:46There's some very exciting, really compelling research in the past decade around this concept of physiological co-regulation or biological syncing, which is when our nervous systems sync to one another. And you might wonder, well, who are they going to sync to? And research shows that we sync to the person of the highest perceived power. so we sync to our leadership and for leaders and whether you're a parent or you're a boss or you're the front desk worker at a dental office you have an impact on those around you people are syncing to your nervous system so it can create a real sense of responsibility for leaders to make sure that they're learning the tools to regulate themselves so that they can have the right impact on those around them.

32:46Yeah, that brings us back to connection, which can be one of the strongest safety signals of all. And I think hearing you share this and reading about it, I know that deep rest is not only about being alone. Social support can signal safety in really powerful ways. So what does rest through connection look like for someone who feels lonely or whose support system is thinned. So one of the really neat discoveries from working on our deep rest theory is that traditionally a lot of deep rest practices are practiced in groups. Whether that's prayer or yoga, going to temple, choir singing like I mentioned earlier, there is a kind of historical tradition of doing these things together.

33:41And what that really shows and represents is that when we're alone, our bodies are actually out of alignment from their natural states. And this was written about in a theory called social baseline theory, which is the theory saying that our bodies and minds really operate best when we're around other people. and that doesn't necessarily mean that we have to be in constant communication because in fact when you're choir singing or when you're in a yoga class you're not having deep meaningful heartful talks you're just doing an activity together and so what i would suggest to people who are feeling lonely where can you go in your life whether that's a coffee shop or a library where you're around others and that feels good for you and maybe just start there that's wonderful advice as somebody who is a quite an introvert myself.

34:36That's a good place to start. Now, Alexandra, speak to the person listening right now who is busy, they're tired, they're thinking, this sounds nice, but I do not have a moment in the day to do this. What is the smallest deep rest practice that can make a noticeable difference this week, right now? And what might they notice first? I would say the biggest, easiest tool you can use is checking in with your body, paying attention to the signals of your body. And one slow breath is a good way to do that. Another way to do it is to just switch your attention, your mind's attention, to any sensation that you're feeling.

35:20Our modern world has overly emphasized our cognitive abilities. Like we're pretty much focused from the neck up all the time. And we often are ignoring all the signals of our body. And sometimes like all of a sudden you realize, oh my gosh, I need to eat. I haven't eaten. Or you get dehydrated. You haven't had any water because you're ignoring the interoceptive signals that your body's sending you about what it needs. And so just taking a moment to listen in and to tap into your body is a first way to start to pay attention to the different arousal states you're in and hopefully eventually be able to figure out, wow, my body needs rest or my body needs to take a break or to turn on some music or to get outside and take a walk.

36:10Being able to give it what it needs in that moment to feel back to wholeness is really what the root of nervous system regulation really is. Dr. Alexandra Crosswell, this conversation has really been grounding and galvanizing. Thank you for helping us. Remember that rest isn't weakness. It's about wisdom, actually. And I'm grateful for your work and your voice here. Thank you so much.

36:41Dr. Croswell makes a case that rest is not a luxury add-on. It's a biological requirement, and it's not the same as just zoning out. Deep rest is about giving the brain and body enough evidence in real time that things are okay, so the systems responsible for repair and maintenance can come back online. It's also a reminder that the most effective health tools are often the ones that help us shift states, not just push harder in any given direction. And that brings us to sleep, the most powerful version of restoration most of us will ever experience. If deep rest is a coordinated state of safety and repair, then sleep is our nightly opportunity for that process to run at full strength.

37:29But even in sleep, the details matter. The way we position our bodies can affect breathing, reflux, spinal alignment, and how rested we feel when we wake up. In today's TEDx lesson, Rachel Marie E. Salas walks us through the science of sleep positions. There's a bunch of them. Side sleeping, back sleeping, stomach sleeping, and most of us move through more of these than we realize. With no fees or minimums on checking accounts, it's no wonder the Capital One bank guy is so passionate about banking with Capital One. If he were here, he wouldn't just tell you about no fees or minimums. He'd also talk about how most Capital One cafes are open seven days a week to assist with your banking needs.

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38:30Now here's your TED-Ed lesson of the day. In the 1970s, psychoanalyst Samuel Dunkel proposed a curious, albeit almost completely unsubstantiated theory that the position you sleep in reflects your personality. For example, preferring to snooze in the so-called royal position indicated self-confidence, while sleeping semi-fetal meant you're sensible and well-adjusted. While Dunkel's ideas lack any definitive proof, how we sleep can impact our health. So what's the best position to sleep in? Sleep positions go by countless creative names. The zombie, mountain climber, free-faller, and soldier. Yet sleep experts typically simplify them into four basic types.

39:22left side, right side, stomach, or back. Until the age of one, it is recommended that babies sleep on their backs to lower their risk of choking and suffocation. As young children, we start to move around more in our sleep, usually ending up on our sides and backs. And this tendency to avoid sleeping on our stomachs only grows with age. By adulthood, most people prefer side sleeping, while fewer favor back sleeping, and stomach sleeping is the least preferred overall. But of course, individual sleep styles are highly personal. Some people are sworn belly sleepers, while others can't nod off unless they're sprawled out on their backs.

40:07How we spend the night affects our bodies in several ways. Different sleep postures shift the relative positions of our internal organs, which can either relieve or worsen certain health issues. Others can leave the spine unsupported, straining nearby tissue, and preventing the muscles in the back, hips, or neck from fully relaxing. This can then lead to tension and stiffness in the morning. Take, for example, the least popular position, sleeping prone. Of the four, this also tends to be the least recommended by sleep experts, as it's thought to stretch the natural curvature of your spine. Yet there are unique situations when lying on your stomach may be beneficial.

40:52For patients with certain respiratory conditions, for example, it allows the back of the lungs to expand more freely. Sleeping on your back, on the other hand, is often preferred by those with lower back pain. When paired with a small pillow under the knees, this position allows the spine to maintain its natural curve. However, it may be less than ideal for your sleep partner. For some people, lying on their back can cause the soft tissues of the throat and tongue to collapse into the airway. Then, as the body tries to pull air through, these tissues vibrate, creating the sound we call snoring.

41:33This is also why people with sleep apnea are often told to avoid this position. This condition already involves pauses in breathing, and back sleeping can increase the likelihood that the airway collapses completely, blocking airflow. Today, most experts generally recommend side sleeping, particularly when combined with a pillow between the knees to better align the spine. But, as it turns out, which side you lie on may make a difference. For example, studies show that sleeping on the left side often reduces heartburn symptoms for those with acid reflux. Your stomach is primarily located on the left side of your body, so this position situates it below the esophagus, allowing gravity to naturally keep stomach acid from flowing back up.

42:24However, for people with congestive heart failure, who often have an enlarged left ventricle, sleeping on the right side can help relieve chest pressure and improve their overall quality of sleep. Clearly, there's no one-size-fits-all answer, and attempting to reap the benefits of any one position can be tough, since most people shift positions 20 to 30 times per night without even knowing it. Pillows and other sleep training devices can help you stay in one place. But fortunately, unless you have a specific concern, sleep movement isn't always a bad thing. It's how your body naturally relieves pressure, responds to discomfort, and ultimately prevents injury.

43:09So, the next time you find yourself drifting to the free-faller, soldier, or zombie, you can rest assured.

43:22That was a TED-Ed lesson by Rachel Marie E. Salas. And that's our show for today. Thank you so much for listening. TED Health is a podcast from TED, and I'd love to hear your thoughts about this episode. Send me a message on Instagram at ShoshanaMD. This episode was produced by me, Shoshana Ungerleiter, and Jess Shane. Edited by Alejandra Salazar and fact-checked by Vanessa Garcia-Woodworth. Special thanks to Maria Lages, Farrah Degrange, Daniela Balarezo, Constanza Gallardo, Tansika Sangmarniwang, and Roxanne Highlash.

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