In today’s fast-paced world, sleep deprivation has become alarmingly common. Many people underestimate the role of quality sleep in their overall health and well-being, leading to a variety of issues. In this episode of The Hard To Kill Podcast with host Dave Morrow and guest Kirk Parsley, a retired Navy SEAL and sleep expert, we delve into the fascinating topic of operator syndrome, the dangers of taking Ambien, and the crucial importance of getting enough sleep.

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Listen to our first episode, “Sleep Or Die,” here

Operator Syndrome

The discussion begins with Dr. Parsley’s observation that many Navy SEALs were suffering from performance issues rather than physical injuries. This led him to identify a pattern he called “operator syndrome.” Dr. Parsley discovered that low anabolic markers, high estrogen levels, high inflammation, and poor insulin sensitivity were common among these individuals. This revelation urged him to investigate the impact of sleep on their performance.

The Dangers of Ambien

One surprising finding was the prevalent use of the sleep aid Ambien among special forces soldiers. Dr. Parsley discovered that Ambien not only interfered with the quality of sleep but also reduced essential deep and REM sleep. Deep sleep is known as the most anabolic time for physical recovery and muscle growth, while REM sleep is critical for cognitive processes such as memory consolidation and emotional processing. Dr. Parsley emphasizes that Ambien, when combined with alcohol, further exacerbates these negative effects.

“I took Ambien almost every night, or maybe every night…I wonder if that can be important…it destroys about 40% to 60% of the quality of your sleep. So it’s a net negative. Like you’re losing sleep by taking sleep drugs.”— Dr. Kirk Parsley


The Power of Sleep

Dr. Parsley’s research demonstrated the transformative effects of improving sleep on soldiers’ performance, mood, cognition, memory, motivation, and overall health. By discontinuing the use of sleep drugs and alcohol, these individuals experienced remarkable enhancements in various aspects of their lives. Chronic insomnia was also discussed, highlighting its detrimental impact on life expectancy.

“Chronic insomnia is basically associated with a lower life expectancy of about ten to twelve years. Chronic use of sleep drugs is the same. I don’t think the sleep drugs are doing anything to cause death. I think it might be accelerating the decay because you’re lowering the quality of your sleep.” – Dr. Parsley


Sleep Deprivation and Health Implications

Sleep deprivation goes beyond feeling groggy the next morning. Dr. Parsley sheds light on the links between chronically disrupted sleep, inflammation, cardiovascular problems, and degenerative neurological diseases like Alzheimer’s and Parkinson’s. Lack of quality sleep not only hampers recovery but also contributes to chronic inflammation and elevates stress hormone levels.


Strategies for Improving Sleep

Dr. Parsley shares his expertise on combatting sleep issues. He emphasizes the significance of circadian rhythms, the deleterious effects of shift work, and the need for an adequate number of sleep hours. The guest also suggests refraining from pharmaceutical sleep aids and instead focusing on lifestyle modifications, proper nutrition, and stress management techniques.




The Hard To Kill Podcast provides a valuable platform for exploring operator syndrome, the hazards of Ambien, and the profound importance of sleep in our lives. Sleep deprivation is an issue affecting countless individuals, but understanding its implications and adopting healthier habits can lead to transformative changes. Prioritizing quality sleep is crucial for optimal health, performance, and overall well-being. So, let’s put an end to sleep deprivation and embrace the power of restorative sleep. Don’t forget to tune in to the podcast episode for a deeper exploration!

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Dave Morrow [00:00:00]:

Hey, real quick. If you’re a repeat listener to podcast and you really enjoy the content that is being put out on the airwaves here, I’d really appreciate if you go and leave a rating and a review on your favorite podcast app every time you do so. It allows somebody else to find this podcast, find it in their search feature, and potentially change their lives forever by listening to some of the best experts on the planet on fitness, health, and nutrition. So do your 10 seconds of altruistic behavior today and go leave a review and a comment, and I will love you forever. Peace. This is part one of a two part episode with Dr. Kirk Parsley. Dr. Kirk is a return guest on the podcast, and his expertise is all in sleep. This is an important topic if you are a veteran or a member of the military, because, as we know, this is something that often gets broken very early on in our careers. He is a Navy Seals and used to work with his Seals on fixing their sleep issues. In this episode, we’re actually going over things like operator syndrome, what it is and how to fix it, why you should never take Ambien, and the reason for why we sleep as a species. Stay tuned. Welcome to the hard to kill Podcast. With me. Your host, Dave Morrow. The goal of this podcast is to be a catalyst for change in the health and wellness of our military community and make each of you harder to kill. My mission is to help 100,000 veterans lose 2 million pounds by listening to the amazing wisdom and knowledge shared by my guests. Sit back and enjoy. Hey, folks, sitting with Dr. Kirk Parsley. Dr. Kirk Parsley is a retired Navy Seal medical doctor and specializes in sleep. This is actually his second time on the podcast, and it’s almost three years to the day when we had the conversation on episode 31. Seems like a lifetime ago. So, Kirk, thanks so much for coming back on the podcast. How are you doing?

Kirk Parsley [00:01:51]:

I’m doing well, man. Thanks for having me back on. I’ve forgotten all about you.

Dave Morrow [00:02:00]:

That’s not insulting, believe it or not. I totally get it. That’s the power of the Internet. I was like, hey, you know what? I should reach out to Kirk. I got a bunch of new questions on. I saw that, and.

Kirk Parsley [00:02:17]:

I saw that on my schedule. I’m like hard to kill. Oh, man, that’s a blast from the past. I haven’t seen that in a long time. Yeah, totally forgotten about it.

Dave Morrow [00:02:27]:

It’s like, oh, my God, that guy’s still around.

Kirk Parsley [00:02:31]:

He made it through COVID.

Dave Morrow [00:02:35]:

Yeah, exactly. Well, yeah, funny you mentioned COVID. Our conversation, like, I was just saying offline before we went live here. It was the day where Quebec decided, okay, it’s game on. It’s Pandemic city. It’s pandemania. And I was supposed to record this in the gym, and it just didn’t happen. I didn’t go into the gym. I recorded in my car. Everybody was freaking out. It was like the end of the world. And that was the day that we recorded. And it stuck so well in my mind. And then in hindsight, I was thinking, well, this is going to be done in a few weeks. People are freaking out. People freak out all the time. I’m not freaking out. We’ll be fine. I’m sure you’re fine. Almost three years later, we’re finally getting out of it. And I think it’s relevant because this.

Kirk Parsley [00:03:27]:

Screwed up all my rhythms, and I.

Dave Morrow [00:03:30]:

Think it screwed up everybody’s rhythms, and that includes sleep. So, Doc Kirk, guess, let’s get into it. Why is sleep so important? Why did you dedicate your entire practice, your main effort to ensuring that especially your seals back in the day were sleeping?

Kirk Parsley [00:03:51]:

Well, I’d love to say I had some brilliant insight and saw something coming, but that’s not the case at all. When I showed up there as the physician, after having been a seal there, she’s like a decade before I fully expected to go in there and do a bunch of sports medicine orthopedic stuff and musculoskeletal injuries. That’s what I expected we’d see. And we had our fair share of that, but I had a big staff for that. But what guys would come in my office and tell me about were basically just performance issues, right? So it wasn’t disease. And I was a Western trained physician who knew how to recognize and diagnose and treat diseases, but they just weren’t performing like they felt they should. They’d noticed a big drop off in their motivation and their cognition, their memory, their concentration, their mood, being able to control their mood, their verbal fluencies, their ability to learn either cognitively or physical task, shifts in body composition, losing muscle, gaining fat, getting weaker, feeling more pain, just feeling worse. Everything was a lot harder for them. And I didn’t have any idea. I just kind of did this shotgun approach and tested every kind of lab I could possibly think of that could have anything to do with their performance. And I saw this pattern, which I dubbed the Seal syndrome because I lack imagination. It’s since been covered in a more academic sense and published in peer reviewed journals, and they’re now calling it the operator syndrome. But it’s basically really low Anabolic markers like low testosterone, low DHT, low DHEA, low growth hormone, high estrogen levels, high sex hormone binding globulin, high inflammation, high oxidation, fairly high insulin like fasting. Insulin levels were pretty high, insulin sensitivity pretty low. Pretty poor for these guys who were working with nutritionist and were young and fit and working with strength and conditioning coaches and doing everything right. I honestly didn’t have the slightest idea what the hell was going on. And somewhere in the midst of 30, 40, 50 guys coming in my office and telling me the same story. One of them said something about you all, just get a list of their meds. And he said something about taking Ambien. And I took Ambien almost every night, or maybe every night. I remember kind of a light bulb going off over my head and going, that seems really common, I wonder if that can be important. But I had no idea. So I just made a note of it and then I went back after he left, and I went back to my records and I kept shadow files in my office. So I had my own personal files of everybody who’d come to see me. And every single guy who had been in my office was taking Ambien. And I don’t remember exactly, but I would say really close to 100% of them were also taking that ambient with alcohol. I didn’t know anything about sleep. I never had a single class on sleep in medical school. I didn’t know anything more than any of the seals knew. I didn’t know any more than my gardener knew about sleep. I knew we did it. I knew it made us feel better and it was some kind of refreshing, regenerating thing. And that’s about all I knew. And so I started looking into sleep and lo and behold, everything good that happens when you’re asleep. It took me a while to learn it all, but all of your sex hormones are regulated while you’re asleep. And about 90% to 95% of all the anabolic hormones you’ll secrete in any 24 hours period while you’re sleep, and particularly the vast majority of that in the first 4 hours of sleep. And so I thought, well, I wonder if ambient or alcohol could be impacting that. And so I started doing some research. And what most people don’t realize is that when a pharmaceutical industry applies to the FDA for approval of a drug, they actually own the research that they give the FDA. So they do their own research and then they turn in what they want to turn in. And they don’t turn in what they don’t want to turn in. If it doesn’t help their case, they don’t turn it in. But unfortunately for them, fortunately for us, if they get sued and it’s suspected that they knew the risk that they’re getting sued for, then they make them pull up the skirt, show the whole thing, and they dump all the data. So it turns out that they knew that ambient interfered with your quality of sleep. And then ironically, it only makes you fall sleep about 13 minutes faster on average, and you sleep about 37 minutes longer on average, but it destroys about 40% to 60% of the quality of your sleep. So it’s a net negative. Like you’re losing sleep by taking sleep drugs. You just feel like you’re getting sleep. So it’s more of a psychological benefit than anything. And so I figured Ambien primarily, and we can talk about details if you want to. You can kind of break sleep into two phases. There’s a deep sleep and there’s a REM sleep. The REM is the rapid eye movement, like most things in biologists, named after an observation, namely rapid eye movement underneath your eyelids. But deep sleep is when your brain waves are the slowest. But it’s the most anabolic time of your life, right? It’s the most anabolic time of any 24 hours period is while you’re in deep sleep. And that’s when you work out. If you lift weights or if you run or swim or whatever, you do anything to a strenuous level to try to get better at it. You don’t actually get stronger while you do it, right? You get weaker. So if I go in the weight room and I lift as much weight as I can lift for ten times and I do that three or four sets, I walk out of that weight room considerably weaker than I walked into it. Why do I get stronger? Well, I get stronger when I go to sleep, and I go to sleep and my brain and my body uses today as a template to say, hey, what do we need to be better at tomorrow? It’s like, well, these muscles got way overtaxed, and if you work out hard enough, you actually rupture muscles, you actually rupture muscle cells, kill them off, and the muscle fibers will try to grow back stronger or more enduring or more flexible or more pliable, whatever it is that you’re training them to do. REM sleep, though, is primarily when all the cognitive stuff is happening. So everything that happens to you during your day, you rehearse at night multiple times. So you go through it, you relive it. If there’s something emotional that happened, you categorize that, right? And you put that sort of in the rank order of how emotional really is this not how emotional was I at the moment? Right? Because we all know you can get overly emotional at something really stupid in the moment. And then when you go to sleep, you categorize that and go, oh yeah, well, dirty dishes in the sink ranked next to seeing one of my friends get killed. Pretty low, right? I should put that way down here on the list.

Dave Morrow [00:12:37]:

At least we hope.

Kirk Parsley [00:12:38]:

Yeah, at least one would hope. Yes, one hopes. And then also anything that you learn. So if you learned something from our podcast today, you’re going to rehearse that tonight, and you’re going to think about it, and you’re going to form connections between what you and I talked about today and what you already knew. And the more durable those pathways are, the faster you can access that information. And the more pathways there are, the more directions you can access that information from. And now you actually learn that information. You can work from multiple angles on it. If you’ve ever taken sort of like an abstract math course or learned a new language. Most people have the experience of going to bed thinking about something or having a problem during the day that they couldn’t solve and then waking up in the morning and going so obvious, I know what the answer to this is, right? I know how to say that, or I know what I’m missing in this math equation, whatever. And that’s simply because you attached it to new information and now you can think of it from different angles and you really know it. And then you’ll rehearse every conversation that you’ve had, whether it was something you’re learning or not. It’s just like anything that you learn and it could be a physical skill as well. You’re paralyzed during REM sleep. So if you’re practicing, if you’re working on your boxing skills, well, when you rehearse that, you don’t really want to act out those boxing skills, right? Your spouse wouldn’t approve of that, especially.

Dave Morrow [00:14:16]:

With your wife next to you.

Kirk Parsley [00:14:17]:

Yeah. Would not be a good thing. So your muscles get paralyzed and you’ll rehearse what you did. But all those muscles, like the nerves will activate that are going to those muscles is just as though you are actually doing it. It just doesn’t reach a threshold to actually cause movement. And so what I learned was that sleep drugs like Ambien, lunesta, they decrease REM sleep by about 80% and they decrease deep sleep by about 20%. And then alcohol does the opposite. So if you’re having a couple of cocktails to wash down your ambient and you know, special forces guys, if one’s good, two is better, three is probably great. So they’re taking way more than they should, chasing that down with a couple of cocktails. And they’re laying down in bed and they’re going unconscious for 4 hours, 5 hours, and then they’re waking up wide awake and they just don’t feel like they can go back to sleep. So they come up with the clever plan. They go, Well, I’m just going to get up early. Now it’s 04:00, whatever. I’m going to get up early, I’m going to go into the gym, I’m going to work out really hard, I’m going to go to work. I’m not going to take any naps, I’m not going to take any breaks. And when I come home tonight, I’ll be really tired. And then the same thing happens that night. The same thing happens the next night. And so these guys have been running this program for a long time and we select out all military does, but the Seals especially, we select out for people who can handle sleep deprivation well, right. We have a full week without any sleep. Essentially, you wake up Sunday morning and then sometimes Sunday evening you break out for Hell week and then you don’t get secured until Friday afternoon. And so it wasn’t a culture that really thought sleep was all that important. Sleep was something that you could just push past. If you’re mentally tough enough and you’re strong enough and you’re dedicated enough and you really wanted it, you wouldn’t really have to sleep. You can just push past it and get a nap here and there, whatever, and you’ll be fine. And that’s what I thought, too. I spent all of college and all of medical school and residency sleeping about four or 5 hours a night because I was a go getter. I was getting after it. I was going to get up earlier, work harder. I got up at 330 in the morning when I went to medical school, so that was the only time I could work out, so I could go to the gym before going into school and then school all day, come home. I had a family. Anyway, after figuring out all of that, I said, well, let’s see what happens when we get guys off of sleep, drugs and alcohol. And lo and behold, we take guys whose testosterone would be like, in the lowest 20% of the normal range, and we take them to the highest 20% of the range. Same thing with free testosterone. Same thing with growth hormone. Knock down all their oxidation, knock down all their inflammation, improve their insulin sensitivity, and their performance goes up and their mood improves, and their cognition improves, and their memory improves, and their motivation improves, and their body composition improves. Now, I’m not going to sit here and say that the only thing that was going on was that obviously we have a lot of brain injuries, a lot of traumatic injuries, a lot of traumatic brain injuries, a lot of PTSD like symptoms and things like that as well. So there were other things going on, but that was the biggest piece of the puzzle. And so I started working with guys to do that. The military was not a big fan of me doing that. They kept cracking the whip on me, telling me that I was practicing outside of my scope and doing things that I wasn’t hired to do and all that. And I was like, whatever, I’m here for the guys. I don’t care what the leadership thing. So pretty much sacrificed my career over that. But I was like, making commanders not nearly as important to me as helping out my brother, so I just kept doing it. And then over a couple of years, I kind of convinced the naysayers and started gaining some traction in that field. And we would have guest lecturers come in and talk to the guys before and after deployment to talk to them about various things. And we’d bring in some kind of bigger name people that the teams followed, their podcast or whatever. So we’d bring in like, Rob Wolf or bring in Dave Grossman to talk about Psychology of Killing or John Wellborn to talk about strength and conditioning or whatever. We just brought in these guys, and then I shared the stage with these guys at these events because the military had me for free, so they’re going to obviously have me lecture every time. And then I just got to know all those dudes, and they started inviting me onto their podcast and inviting me to do symposiums with them. And I became the sleep guy, which wasn’t really my intention at all. I was a performance guy in my mind. I was trying to help people perform better, and sleep was just the thing that that audience needed. But I was just as adamant about exercise and nutrition and stress. Mitigation when I met Rob Wolf, we really hit it off because he’s this nutrition guy coming in, lecturing on nutrition. He spends 30% of his lecture on sleep, and I was the sleep guy. Lecturing and I spent about 30% of my lecture on nutrition. So we hit it off, became fast friends, went on his podcast, and now I’m the sleep doc. It is what it is. I work with private clients, and I work with a lot of ex special forces guys and some active duty guys, and I still do everything performance related. But when people hire me to lecture or bring me on their podcast, it’s usually for sleep.

Dave Morrow [00:20:47]:

Yeah, you got to go where the energy flows.

Kirk Parsley [00:20:51]:


Dave Morrow [00:20:51]:

That’s where the energy was taking you, because you had that experience with your seals. You were saying the experience with command, they were saying, like, hey, what are you up to? Quit working on the sleep stuff, because that falls outside, like you said, of their kind of purview, of their box, when in actuality, you’re applying just basic scientific method to a problem. Hey, this is a problem. You observed it. You came up with a hypothesis, he tested it, and he got results, which is kind of how I expected doctors to always operate. However, over the last three years, I’ve learned, I guess, the hard way, that that’s not really how the medical profession works. So moving there, that’s such an impressive arc.

Kirk Parsley [00:21:43]:

Yeah, trust me, that’s how the vast majority of physicians and healthcare practitioners would like to practice, but they run into the same problems that I do, that I did. Unfortunately, if you’re in the civilian sector, they can just fire you. I had a contract with the military. I knew they weren’t going to fire me, so I was just going to do what I needed to do. But that is clinical practice, right? An evidence based medicine is supposed to be, hey, I’m aware of the research that’s out there. I’m aware of the physiology here. I’ve learned the basics in that. I’ve done my best to stay current on that. But in my day to day practice, these are the things that I found help my patients the most. That’s what evidence based medicine is supposed to be. Now, evidence based medicine is you work for a hospital who essentially works for an insurance company who essentially works for the government. And they say, these symptoms mean this and you follow this algorithm and you give them that. And if that doesn’t work, then you can give them that. And if that doesn’t work, then you can give them that. I have doctor friends that I was in the military with who’ve gone out into private practice and they’re so frustrated because, say, they’re er physicians and they have people coming in with these health problems and they know for a fact that 90% of their problem is diet, right? Because they’re obese type two diabetic, or close to type two diabetic, and most of their symptomatology is coming from this. And they just want to sit down and talk with them for 30 minutes and tell them about nutrition and how they can fix all this and how easy it is to fix this with nutrition. But they can’t do it. And if they do do it, they get in trouble like they don’t have the time to do it. And if they do find the time to do it, they still get in trouble for doing it. It’s going to be a long time before anybody regains confidence in the medical system, especially after this debacle. COVID I agree.

Dave Morrow [00:23:53]:

Absolutely. And that’s why I have experts like yourself and other doctors like Dr Ovedia, cynthia Thurlow. The body of knowledge that exists is vast. It’s deep, it’s conveying it, though not in your doctor’s office, but listening to it here and then taking the personal responsibility to put it into action. And I think you hit it perfectly. The idea here that your doctor is going to kind of come up with this solution is not realistic because they’re beholden to a higher power. It sounds like they beholden to God, to a higher authority, as in the government, the insurance companies. So your best interest is not really at play. And I had a consult with a potential client not too long ago. 35 year old guy. He’s going to the VA. He wants to lose weight, he wants to get healthy, he just wants to be better. He’s got kids, I get it. That’s who I deal with almost all day. And he shows me his bucket of pills and I said, Dude, how many pills do you want? He’s like about twelve.

Kirk Parsley [00:24:55]:

I said, yeah.

Dave Morrow [00:24:56]:

Wow. How much are you sleeping I always ask, how much are you sleeping a day? He’s like, A good four or 5 hours. And right away I said, oh, my God. Nutrition is good right off the bat.

Kirk Parsley [00:25:08]:

Without you can’t use the word good when you’re saying four or 5 hours. Yeah.

Dave Morrow [00:25:17]:

It’s alarm bells, right? It’s alarm bells to speak more to that. Maybe you can answer this question. All of these issues are really important. Taking too many pharmaceuticals to try and get the sleep. Just training a bit too hard. Mild traumatic brain injury. If we pull it right back down to the base level. I don’t have an answer for this, and maybe you do, but what is the biological or genetic reason why we even need to sleep? Why did this appear on the spectrum of the animal kingdom? I think every animal needs to sleep. I may be wrong on that. I got to go back into my biology notes. But we definitely need sleep, and it seems like it is such a the risk reward. You have to go to sleep and be paralyzed for hours or close to it when predators and everything can come attack you. It seems like a really big gamble to have this system where we need to shut everything down in order to repair and rebuild. What is it? Why do we have sleep as part of our daily biological imperative?

Kirk Parsley [00:26:31]:

Yeah, well, I love the way you’re thinking is going with that. It’s an argument that it’s pure speculation and unprovable. But what it says to me, the point you’re making is something that stood out to me immediately when I’m not a big fan of this phrase hack biohacking. I think there’s hardly a more arrogant idea in the world to think that you’re 40 years old, and now you understand hundreds of thousands or millions of years of evolution, and you can beat it because you read some papers or something and you got some clever tricks. To me, that means you’re trying to get something for nothing. You’re trying to get a reward without doing the work. So I hate those ideas, but I was working with a population that very often just simply didn’t have the opportunity to sleep as much as they needed to sleep. So trying to figure out, is there something that we can do to speed up your sleep? Can you sleep harder and faster? And I started thinking about it, and I thought, well, you know, evolution selects for the fittest, right? And to your point, how vulnerable we are as a species, first of all, we’re vulnerable species, period, without a weapon. Neither one of us could fight an angry raccoon, right? We’re nowhere near the top of the food chain without weapons. So we’re pretty vulnerable if we’re caught without our weapons by just about anything. And then we can’t see at night worth a damn. So it makes sense that we don’t want to be out at night. But you’re still vulnerable, right? And people snore, and people make noises, and there are animals that see very well at night, and there are animals that see with thermal imagery, and there are animals they can smell you, and they can stalk, you know, can come up on you while you’re asleep. And I thought, well, evolutionarily, if there were people who evolved to sleep less, natural selection would have favored that, right? And maybe they did, right? Like, maybe humans slept 16 hours a day, right? Like, lions sleep 20, 21 hours a day. Maybe humans originally slept 16 hours a day, and those that slept 16 hours a day died really quickly. Right? They didn’t reproduce that often. Who knows? But basically it takes a long time to get there. You have to think about this stuff for years. Like, I’ve been thinking about this for over a decade now. But to me, like, being asleep and being awake is just a continuum. It’s all part of being a human. It’s all part of being alive. To validate what you said earlier, every mammal on this planet sleeps. There’s even sort of a sleep wake cycle for plants. I mean, so, like, almost everything has some sort of recovery period. And the only animal on this entire planet that will sleep deprive itself on purpose are humans. No other animal will get less sleep than it feels like it needs, unless it’s being stalked. If something’s stalking it and they’re worried about being prey, then they’re just going to sleep as much as they have to. Or if they’re starving, right? If their food source is drying up, then they’re going to get up earlier and stay up later so that they can travel greater distances and find food, right? So it makes sense to assume that our brains perceive sleep deprivation the same way, right? Because why else would we sleep deprive ourselves? Every other mammal only does it if they’re afraid of getting eaten or killed or if they’re afraid of starving to death. So there’s probably some evolutionary triggers in there that makes our bodies believe, our brains believe that we’re starving or we’re under threat, and that’s why stress hormones go up. That’s one of the reasons stress hormones go up. But anyway, to answer your question, when you go to sleep, there’s a part of being awake. There’s a time of day when you’re awake. And what that means is that your brain is engaged in different activities, right? So your brain is engaging the environment, right? So I’m using my brain power to look and see and smell and taste and feel and whatever. And I’m interacting with the environment in the way that’s moving me towards the goal that I want, ancestrally moving me towards food or shelter or reproduction or something along those lines nowadays. Moving me towards building a business or Netflix, whatever, raising my family, fixing my house, like, who knows, whatever the hell you’re using your energy for every day. But your brain can only engage in that activity for so long. Just like, if you’re going to run or you’re going to walk or you’re going to lift things, your body can only do it for so long, and then it needs to recover. The exact same thing is happening with your brain and your body, but it’s primarily your brain. At the end of the day, it’s like, hey, we’re spent, man. The neurons are like, we’ve had it. We’ve done what we can do. We got all these waste. Products we need to get rid of. Our energy stores are low. The neurotransmitters are low. There’s a ton of adenosine built up in our brain. So every cell in your body uses adenosine triphosphate as an energy source. You take off a phosphate group and it releases a bunch of energy, and so it goes from three to two to one. So triphosphate to diphosphate, to monophosphate, and then you just have adenosine. And adenosine is the trigger in your brain to say, hey, you really need to sleep. You’ve overdone it. The adenosine gets so high, if you’ve ever stayed up for 36 hours, 48 hours in a row, you could literally lay down on gravel with thorns and whatever in the middle of the day and just sleep, the pressure is so high that your brain is like, you need to shut down. And so the first thing that happens is you’ve probably heard of this point of the glymphatic system, which basically is like a shrinking down of the cells that control the structure of the brain and allows the cerebral spinal. Fluid to get through in places where it doesn’t ordinarily get and it gets rid of all the waste products, and then it allows nutrient exchange. And so you can build back up the working material of whatever cell you’re talking about. And that’s true for every cell in your body. You can think of yourself as you can think of a cell as just an infinitesimally small version of you. Every cell in your body needs respiration, right? It has to get oxygen in there. It needs to take in nutrients. It needs some certain amount of minerals and certain amount of hormones and chemicals, whatever, to do the work that it does. And it does that work, and then it produces waste products, and then it needs to recover. And we’re the same way. So every cell in our body needs to recover. That’s why we have a circadian rhythm. And a circadian rhythm is every cell in our body. Right? It’s not just sleep, wake cycle. Every cell in our body is saying, now’s the time to recover. That’s why when you do something like shift work and you work when you should be asleep. And there’s plenty of professions where people to do this their whole career. They’ll work 20 years at night and sleeping during the day. Well, those people die twelve to 16 years earlier than their peer than peers who don’t do shift work. And that’s because there’s a circadian mismatch, right? There’s also something called an ultradian rhythm I won’t get into, but it’s all very similar. And basically it’s like your cells are spending time doing, working and interacting with the environment, and then we need to rest and recover, restore, regenerate. The whole purpose of me going to sleep tonight is to repair from today everything I did to damage myself or deplete myself, repair, replenish, and then prepare for tomorrow, right? So that when I wake up tomorrow, if I can repair 100% and I can prepare 100%, then I wouldn’t age. Right. I would wake up every day exactly the same. That’s the purpose of going to sleep. Now, as we get older, our ability to recover gets worse. So if you think of it like a kid, you think of a 14 year old kid, they go to sleep. They need more sleep than we do because it’s more anabolic and they’re doing more work, but they’ll go to sleep. They sleep for 1012 hours. They wake up better the next day than they went to sleep that day. Right. They wake up taller, stronger, smarter, faster. Right. And that happens until somewhere in your early to mid twenty s, then you plateau for maybe ten years. And then about 35, it starts going the other way, and you start waking up a little less every day. And so if it takes 8 hours to recover, and it does, that’s just the facts. When you’re born, contract says you’re going to die, and it takes 8 hours to recover from being awake for 16 hours, that’s just the way that that’s the world you live in. Fight it all you want to, but that’s the truth. And so if you need 8 hours.

Dave Morrow [00:36:37]:

And you choose I’m good on 4 hours.

Kirk Parsley [00:36:40]:

Yeah. If you need 8 hours and you choose to sleep 6 hours, you’ve taken away 25% of your recovery. So essentially you’re choosing to age 25% faster.

Dave Morrow [00:36:55]:


Kirk Parsley [00:36:56]:

And I think a fair definition of aging is that you’re more susceptible to any disease. You’re more susceptible to any disease, you’re more susceptible to die from any cause. That’s what aging really is. Right. It’s not gray hair. It’s not wrinkles. It’s like, hey, I can no longer fight off infections. I can no longer repair my twisted ankle. I can no longer handle something bad in my diet. I can no longer handle this amount of physical activity. I can’t recover from it anymore. I get weaker and weaker and weaker. And that’s what aging is. So you’re just choosing to accelerate that by not sleeping enough? Yeah.

Dave Morrow [00:37:42]:

That makes a lot of sense. That’s just the descent into decrepitude and try to stave that off as much as possible. Your cells are going to age like those telomeres are going to get cut. It’s just how fast do you want that to happen? And not sleeping is just allowing that to accelerate. From what I understand what you’re saying, and going into things that relate to disease. There’s a study that just came out, I know you saw it. 63% more likely to have a heart attack. If you are an insomniac, that is a staggering statistic, because you could probably tell the listeners how many people would be considered insomniacs. To put some context to that number.

Kirk Parsley [00:38:28]:

I would have to see how the research defined it. But usually an insomniac is somebody who chronically. So say like over six for a period of longer than six months is usually the working definition for over six months. I’ve seen it a couple of ways. It takes you over 30 minutes or over an hour to fall asleep when you’ve done everything right in preparation. Now, if you’re not doing anything right, you’re drinking Stimulants and whatever, playing video games or whatever, and you get in bed and you can’t sleep, that doesn’t count. But if you improve lifestyle and you lay down and you can’t fall asleep for over 30 minutes or over an hour, or you can’t stay sleep for an adequate amount of time, then they call that an insomniac. So that research parallels a lot of other research. Chronic insomnia is basically associated with a lower life expectancy of about ten to twelve years. Chronic use of sleep drugs is the same. I don’t think the sleep drugs are doing anything to cause death. I think it might be accelerating the decay because you’re lowering the quality of your sleep. But I think what’s really going on there is that people who take sleep drugs are people who can’t sleep. So it’s no different than somebody who’s an insomniac. So chronic insomnia leads to early death. I’ll possibly get you banned from the internet here, but I don’t really believe the cholesterol model for heart disease. I don’t think that’s accurate. I think it’s stress. I think atherosclerosis is an inflammatory disease, and inflammation is always worse with lack of sleep because one of the things that sleep does is repair and regenerate all of the things that are inflamed. Inflammation is simply a marker for things that need to be repaired. And if it’s chronic enough and it’s not getting repaired, then your body protects it and says, we’re tired of fighting off this infection. And it lays down calcium in your arteries to prevent having to fight that inflamed region of the arterial or whatever vessel it’s in. Sorry, something just shot in my head, something that I read in a book about a year ago, which I’d never thought of. You don’t get atherosclerosis in veins. It’s only in arteries. Although there’s veins that are so thick and have such thick linings that they’re almost indistinguishable from arteries. And then when you take a vein and you graft a vein for a heart transplant, for a cabbage, a coronary artery bypass grafted, and you take it from the calf, you take their vein and you put it where an artery was, and you start pumping. Now that vein can get atherosclerosis. Anyway, interesting aside, explain to me how cholesterol can explain that. Anyway, if inflammation is chronic, then your body walls it off with calcium. You see this in orthopedics sports medicine, where they’ll take some sort of image and they’ll say, oh, there’s a bone spur coming off your bone, right? Do you really think you grew a spur of bone? Does that make any sense? Like, oh, yeah, you had this chronic inflammation, and so you never thought of it. You grew a spike of bone. No, you calcified a tendon. You calcified a ligament. Something that was chronically inflamed got calcified, and it got calcified a lot at the base and less and less as it went on. And it looks like a spike, and it’s like a bone spur, but it’s not. It’s just a calcified connect. It’s some sort of connective tissue that’s calcified. And your brain doesn’t lay down calcium. It lays down a protein, a couple of different proteins, a tau protein, a beta amyloid protein. And those are associated with age associated neurological decline. Things like Alzheimer’s, things like Parkinson’s disease, all of these things are chronic inflammation. And the chronically elevated stress hormones cause that same thing, right? That’s a chronic inflammatory state. And then, of course, cortisol elevates blood glucose. Blood glucose essentially is inflammatory in excess, and so sugary diets also have the same effect. So there’s a lot of people now that are starting to call Alzheimer’s, they’re starting to call that type three diabetes, right? It’s just simply from the same processes that diabetes is causing with everything else, right? The atherosclerosis, accelerated atherosclerosis accelerated nerve damage, vessel disease, all that stuff. Kidney disease, all the liver disease, everything that comes with chronically elevated blood glucose. Same thing is going on in the brain. And we just call it Alzheimer’s or whatever. Ms, maybe. Mild traumatic brain injuries.

Dave Morrow [00:43:58]:

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Dave is a retired infantry officer and Afghanistan war veteran. He’s the creator of the HRD2KILL training programs that were built on the principles that got him from not being able to get out of bed to competing in the Crossfit Open, Spartan Races and the Ironman. You can find more mobility based exercises in his new book, “The Nimble Warrior”, now available on Amazon or tune into his new HRD2KILL Podcast

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