Moment 168: STOP Doing THIS! It's Hurting Your Sleep!: The Fitness Scientist

You might have heard the phrase ‘circadian rhythm’ a lot but never really understood what it meant. In this moment, world-renowned human performance expert, Kristen Holmes gives a simple break down of this rhythm and its massive impacts. Kirsten says that the circadian rhythm is basically physical, mental and behavioral changes that happen over a 24 hour cycle. All of these changes are controlled by a master clock in your brain regulating every cell in your body through chemical signals. Disrupting this rhythm can cause massive health consequence such as cancer, metabolic and cardiovascular disease, as well as mental health issues. The main cause of disruption is from light which confuses the brain’s master clock, this means that you often have to fight aspects of modern life and make sure you protect your sleep by controlling your home environment Listen to the full episode here - Apple- https://g2ul0.app.link/cN1kzWoXLKb Spotify- https://g2ul0.app.link/kO45FhmXLKb Watch the Episodes On Youtube - https://www.youtube.com/c/%20TheDiaryOfACEO/videos Kristen: https://www.instagram.com/kristen_holmes2126/?hl=en Learn more about your ad choices. Visit megaphone.fm/adchoices

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:03Steven Bartlett?

  What is a circadian rhythm? As if you're explaining it to a 10-year-old.

• 0:06Speaker 01

  Yeah, so it's basically physical, mental, and behavioral changes that happen over a 24-hour cycle.

• 0:16Steven Bartlett?

  Okay, so here's my read on it, and correct me if I'm wrong. There's a clock in my head.

• 0:25Speaker 01

  Yes, the suprachiasmatic nucleus

• 0:29Steven Bartlett?

  Yeah.

• 0:30Speaker 01

  is the master clock.

• 0:32Steven Bartlett?

  Okay, which is somewhere in my body.

• 0:33Speaker 01

  It's in the hypothalamus.

• 0:35Steven Bartlett?

  So it's in my brain. And this clock regulates every cell in my body?

• 0:39Speaker 01

  Cell, tissue, organ.

• 0:42Steven Bartlett?

  Okay. And it releases, it controls the release of a chemical which makes those cells, organs, every part of my body, do stuff?

• 0:52Speaker 01

  Yeah, so it is your hypothalamus, so the suprachiasmatic nucleus, it responds to light and it responds to darkness.

• 1:00Steven Bartlett?

  Okay.

• 1:01Speaker 01

  Okay, so that's like the most pronounced entrainment cue for this master clock. And it then tells, it sends signals to every cell, tissue in your body as to what it needs to be doing in the presence of light, in the presence of darkness. And when we are viewing light at a phase of the natural light-dark cycle, that is, if I am awake when I should be sleeping, or I am sleeping when I should be awake, when my body anticipates that, it causes huge amounts of stress in the system. If we do this once or twice, not a big deal. But if we're doing this chronically, okay, it has massive health consequences.

• 1:46Speaker 01

  You know, cancer, metabolic disease,

• 1:51Speaker 01

  you know, cardiovascular disease. 100% of mental health issues, there will be some level of circadian disruption. Okay, so when this light information comes in and tells these clocks what to do, if I am going outside of my natural biological preferences,

• 2:12Speaker 01

  That is circadian disruption. And if you think about how many folks are walking around with circadian disruption, it is mind blowing. I mean, basically, the definition that's been thrown out there is if you are awake from the hours of 10:00 PM to 4:00 AM, if you're awake for two hours between 10:00 PM and 4:00 AM for two days per week for 25 days of the year, you qualify as a kind of card carrying shift worker, and you likely have significant circadian disruption.

• 2:54Steven Bartlett?

  Which means that I have?

• 2:56Speaker 01

  You are at risk for some of the, and it's not going to happen tomorrow, but if you continue on that pattern that I just described, you are putting yourself at increased risk for cancer and cardiovascular disease, metabolic dysfunction, you can have trouble having children. It impacts fertility, mental health, psychiatric disorders. There isn't disease or disorder that circadian disruption doesn't touch.

• 3:25Steven Bartlett?

  So a way of thinking about this, so that I and everyone else can understand, is there's this master clock in our hypothalamus. Look at me, hypothalamus. And this master clock regulates all of the other clocks throughout our entire body. And there's millions of them, basically. And the thing that the master clock is using as a signal, the clock in our brain, is light and darkness. That's its most reliable. That's the signal it cares about, it listens to the most. But there's other signals as well. And if that master clock, so if I'm up at 4:00 AM and I'm looking at a light at 4:00 AM, that master clock is going to start firing off chemicals to all the other clocks. And then all the clocks are going to be out of sync because then when I wake up, it's light.

• 4:08Speaker 01

  You're confusing.

• 4:10Steven Bartlett?

  I'm confusing my body. And it's firing off in all kinds of different ways. So I need to form an alignment, which means basically sleeping at the right time, exposing myself to darkness at the right time, et cetera, et cetera.

• 4:21Speaker 01

  Your body loves regularity. And the problem is modernity is not set up for that. We have access, I think all the circadian research unfortunately was done after the advent of electricity. So we're kind of fighting this access to.

• 4:40Speaker 01

  Constant light. And, you know, we're starting to see the, I think, deleterious effects or the negative consequences of exposure to light, really after the sun goes down. We haven't adapted to blue light after dark, right? After the sun goes down. We have not adapted to blue light.

• 5:01Steven Bartlett?

  Blue light being the light we get from screens?

• 5:03Speaker 01

  Yes. There is a study that looked at the timing of light and its impact on mood and, and brain circuits. And they saw that if you're viewing light between the hours of, again, this is kind of this magic window of time, 10:00 PM and 4:00 AM, it actually has a pro-depressive effect. So it impacts your dopamine system, reward, motivation, right? So when we wonder, you know, oh, why are, what is this mental health crisis? I mean, we have to look at light first. And I, and I just don't know. And, and I think what's hard about the discussion and hard about this behavior is that, you

• 5:43Speaker 01

  know, it's really hard for people to not engage with their phones, you know, before bed. It has its own addictive properties, right? But we just have to understand that these, our, our relationship to light will directly influence the trajectory of our health. There's just no question about that.

• 6:02Steven Bartlett?

  Sleep?

• 6:03Speaker 01

  Yeah.

• 6:04Steven Bartlett?

  So conventional wisdom says it's all about how many hours you spend sleeping.

• 6:10Speaker 01

  Hmm. We already, this has already been shown to be not true. Sleep duration is, is important, right? We can put a pin in that. But sleep regularity predicts all-cause mortality. And this is just recently published, actually, not by my team, but looking at, it was actually a UK biobank, 60,000 people, 10 million sleeps, objective measure of sleep. And they found that sleep regularity predicted mortality and independent of sleep duration. So it's not to say that sleep duration doesn't matter, but that is absolutely incomplete advice.

• 6:53Speaker 01

  How much time you spend in bed doesn't necessarily predict how long you live. It is the degree to which you stabilize when you go to bed and when you wake up that predicts mortality.

• 7:03Steven Bartlett?

  What's going on inside of the body when we increase the? Variability, or that we don't have a regular sleep and a regular wake up time. What's actually going on from like a chemical physiological perspective?

• 7:15Speaker 01

  Yeah, so one of the things that's suppressed is melatonin. And circulating reductions in circulating melatonin have been shown to be linked to every disorder and disease in the body. Every disorder and disease in the body. When we have suppressed or reduced circulating melatonin, that is going to impact us on every level and make us more vulnerable to disease and disorders. So that is probably one of the most important thing. When we have super unstable sleep wake time, we are going to have suppressed melatonin production, which leads to inflammation in the body.

• 7:58Speaker 01

  It's melatonin, I think, is one of the big players in the story.

• 8:02Steven Bartlett?

  Growth hormones.

• 8:03Speaker 01

  Yes, yes. And typically, you know, if you're not going to sleep, if you're going to sleep late, you will not release human growth hormone as you'll get less of a bolus of release.

• 8:17Steven Bartlett?

  And why does that matter?

• 8:18Speaker 01

  That's when all the physical restoration happens. So all the regeneration physically. So if we're bypassing that, we're basically, all the work that we did in the gym or, you know, everything that we did during the day, we're just not going to recover from that in the same way that we would if we were getting that sleep.

• 8:33Steven Bartlett?

  On that point of light, there's a school of thought that says you should look at lights when you wake up in the morning. My partner always gets up in the morning, walks out onto the balcony and sits out there for 10 or 20 minutes in the morning.

• 8:44Speaker 01

  I love that. Yes, I love to hear that.

• 8:46Steven Bartlett?

  Yeah, she's the best. She's so annoying. She gets everything right.

• 8:50Speaker 01

  I love it. Yeah, but for sure that you want to get light within, you know, 100,000 lux is pretty much what you want to get within, you know, five to 20 minutes of waking up to tell your body like it's time to go.

• 9:03Steven Bartlett?

  100,000 what?

• 9:05Speaker 01

  Oh, lux. So just like photon energy. So pretty much if you're. Outside for five to 20 minutes, it sounds like your girlfriend is like nailing this protocol, you'll get all of the photon energy that you need to tell your system that it is time to be awake.

• 9:21Steven Bartlett?

  Can't you just go look into a lamp or something?

• 9:24Speaker 01

  It will just take longer because it doesn't have the same light intensity. But if you're waking up, you know, prior to when the sun gets up, yeah, turn all the lights, you know, you want to try to mimic day as much as possible. And then once the sun does come up, it's good to get outside.

• 9:37Steven Bartlett?

  And before you get in bed, you reference that you read books versus being on an iPad or screens, et cetera.

• 9:46Steven Bartlett?

  Does the same philosophy and principle apply to light exposure before sleep as to food exposure before sleep?

• 9:54Speaker 01

  Oh, no question, right? Absolutely. We want to try to restrict light, basically after the sun goes down, we want to dim our home environment to the degree that we can. We want to try to minimize all artificial light in the lead up to bed.

• 10:08Steven Bartlett?

  All artificial light?

• 10:10Speaker 01

  Yes. Yeah, you want to make it as dim as possible. So, you know, there are a lot of night, like blue light blocking glasses, the filters that you can put on your iPad and your phone, activate all of those. But, but again, like we don't, we want to protect our melatonin release, right? And for all the reasons I kind of have explained, when we don't have it is linked to every disease and disorder, right? So we know this. So we want to protect our melatonin release. And the only way we can release melatonin is by darkness. We need to be exposed to darkness in order for that master clock in our brain to know that it's time to go to sleep. And again, be able to tell our body, our tissues and organs and cells and our body,

• 10:55Speaker 01

  what it needs to do at that moment.

• 10:56Steven Bartlett?

  There's a huge group of people who listen to podcasts like this, and as they listen to these podcasts, they just feel more depressed about their situation. You know, because they've, they believe they're trying their very best and they're still struggling, especially as it relates to sleep. I think I've always wondered what the message one can send to them. And also, you know, I think there is a huge component of sort of personal responsibility and choice that you speak about as well, and that I believe in as well. But what is the most compelling message for those people that do have a choice? They know deep inside, much of it is a lack of discipline. They know they could not watch YouTube. They know they could put their phone away at nine P M. They know they could not eat the cookie super late at night.

• 11:41Steven Bartlett?

  They know they could shoot, deep down, they know they could make a different set of choices. But they listen to these podcasts over and over again. Whenever I have the health experts on, and maybe they even take notes, but they just don't do it.

• 11:52Speaker 01

  Yeah.

• 11:52Steven Bartlett?

  What is the most compelling thing you can say to those people that do have a choice, but continually choose a bad option to get them pushed over the fence to the positive circadian rhythm, body clock loving side?

• 12:11Speaker 01

  Yeah, so if people are trying to develop new habits, you have to understand how that new habit links to your values. So the things that you believe in, the things that you say you care about, right? If I know growth and impact are my two most important values, presence is another one. How, what do I need to do every single day to back into that? So I can align my behaviors with the things I say I care about. And I think when folks are struggling, they don't really know who they want to be in the world. And they don't maybe understand exactly what it is that they value. They're fuzzy about their desires, about their values.

• 12:56Speaker 01

  And I think you end up, when you're fuzzy about your desires and the things that you value, you end up flinging yourself in all sorts of directions, emotionally, physically, mentally. Right? And I think that's kind of the project is figure out what you care about. And then align your behaviors and create outlets in your life. And that frankly, might mean getting rid of people, you know, who don't support those values. And I think we're way too lenient on our circle of friends. And in the sense of, you know, I think we, we keep people around in our life who don't necessarily help us become a better version of ourselves.