125. Kristen Holmes: WHOOP’s Principal Scientist Reveals Game-Changing Research

Speaker 1 Sleep regularity was a bigger predictor of all-cause mortality than sleep duration. Folks who perceived their day as really challenging actually had better night sleep the prior night.

Speaker 1 People who perceive stret are going to have lower stress.

Speaker 2 Wow, I love that. But they didn't.
Oh, they didn't.

Speaker 1 Circadian misalignment, in my view, is the biggest problem in modern society.

Speaker 2 I did a sleep challenge a few months ago with Woop.

Speaker 1 What was astounding to me was that most people actually had no sleep routine at all what was really interesting is ice bath regardless of when you do it is sleep promoting and basically what we saw the fitter you are the more you ice bath the less good it is for your recovery big data combined with artificial intelligence is going to absolutely lead the charge we're getting so close to not having to guess when we take this back to like our original conversation with my athletes like i didn't want to have to guess right i just wanted to be able to keep them healthy i wanted them to be able to thrive if we want to manage load over the course of a season and keep athletes healthy, like you need that data.

Speaker 2 For someone that is genuinely interested in optimizing their health, where do they start? What kind of actionable steps could they take?

Speaker 1 If we really want to optimize our health, the place to start is

Speaker 2 Hey guys, welcome back to the Ultimate Human podcast. I'm your host, human biologist Gary Breca, where we go down the road of everything, anti-aging, longevity, biohacking, and everything in between.

Speaker 2 And as you know, we have a very, very special guest on today, Kristen, who is the global head of human performance and science at WOOP. And I am a huge fan of WOOP.

Speaker 2 And Neil, before the podcast started,

Speaker 2 when you got to the house today, I was telling the team, I'm so excited because We have very different, but very similar backgrounds, big data backgrounds. I come from a big data background.

Speaker 2 So I have like a ton of questions for you. And it's also the first time I'm showing off my illustrious Colorado beard.

Speaker 1 It's working for you.

Speaker 2 It's working for me. My family sort of split over it.
My daughter's like, no, dad, you got to shave it. My son has a beard.
So he's like, I like it.

Speaker 2 So we're going to run it for this podcast. But, Kristen, I'm so excited to have you on the podcast today.
Thank you for taking the time to come here. Thank you for having me.
You know,

Speaker 2 when I say my background is in big data, you know, I was a mortality expert or researcher for large life insurance. And we used big data to very accurately predict life expectancy trends.

Speaker 2 I mean, to the point where large life insurance companies were willing to put tens or even hundreds of millions of dollars in risk on somebody's life based on the modeling that we did.

Speaker 2 And what I find fascinating about your background, besides the fact that you're an amazingly accomplished athlete, incredibly accomplished coach,

Speaker 2 and a brilliant scientist, is that I was watching some podcasts that you were on before. And

Speaker 2 you were talking about your career in coaching and how everything that you were doing on the field and everything that you were doing to prepare these athletes for the game had nothing to do with how they were going to show up the next morning.

Speaker 2 Yeah.

Speaker 2 And

Speaker 2 it was kind of maybe that realization, right? That we're exercising these athletes and we're training them. We're strength training them and we're training them for different positions.

Speaker 2 And we've gotten really good at speed and agility and timing and strength and coordination, but it had no predictability to how that athlete was going to show up the next day.

Speaker 2 So can you talk to us a little bit about that, that journey?

Speaker 1 Yeah, Yeah, it was definitely like the epiphany, you know, when we started,

Speaker 1 you know, having lots of different types of technology that we could measure, you know, what was happening, the adaptation during a training session, you know, and really I was in an Ivy League school.

Speaker 1 We only had the athletes for at Princeton. We only had the athletes for a couple hours.

Speaker 1 And I think we just over-indexed on what those two hours were actually doing to the athletes. And, you know, we had internal load, we had external load, we had, you know, subjective markers, right?

Speaker 1 So we were really, I think, covering our bases in terms of all the things that we could, you know, quantify during a training session.

Speaker 1 But yeah, when they showed up the next day, what we did in the training session actually didn't predict their readiness next day.

Speaker 1 And so the challenge with that is, you know, it's hard to plan practices. It's hard to understand.
It's hard to individualize training, right?

Speaker 1 When, you know, how you are going to respond to a training session, for example, is going to be very different for me.

Speaker 1 So, you know, we started, and this is, you know, 15, 16 years ago, we're like, all right, you know, it's not just the two hours of the training.

Speaker 1 It is the other 22 hours of the day that are having more of an impact. Let's start to unpack those 22 hours.

Speaker 1 And that's when we started to go really deep into sleep, sleep pattern, sleep architecture, sleep timing. We started looking at, you know, macronutrient intake.

Speaker 1 We got a little bit more robust technology

Speaker 1 to look at actually what the athletes were burning during a training session. First beat technology, you probably are familiar with it.

Speaker 1 And, you know, we looked at hydration and we started building these models and actually built a technology and some algorithms to be able to understand hydration levels, understand caloric intake, understand sleep patterns, and really try to develop a model around readiness that could account for the 24-hour period.

Speaker 2 Wow. I mean, that's like way ahead of your time.
I mean, you still won 12 league titles in 13 seasons. So it means something was working, whatever you were doing.

Speaker 2 But I would imagine that early in some of those league championships, you weren't really down the deep, down the rabbit hole in those other 23 hours.

Speaker 1 No, no, we absolutely weren't. And, you know, we knew that we were leaving something on the table.

Speaker 1 And I think that's where, you know, as a coach, you know, I didn't want to leave anything on the table. And I really wanted to help my athletes optimize their potential.

Speaker 1 on the field and off the field. And I felt a lot of my responsibility as a coach was to educate them, right?

Speaker 1 To help them understand what are the factors that are going to impact your attentional capacity, your energy production, your motivation.

Speaker 1 Like I, you know, I wanted them to learn not just, you know, win championships and be a sensational fiacke player. Of course, it's more than that, right?

Speaker 1 It's really providing a performance education over the course of the four years that helped them understand exactly how it is they need to apply their effort so they can take that education and then have it with them for the rest of their lives.

Speaker 2 And, you know, you know, you even talked about how you would apply some of these metrics during a game, like to see,

Speaker 2 you know, when should I be taking athletes off the field

Speaker 2 so that we always have fresh legs. And I've heard you talk about how we never got late into a game or deep into a game, you know, the last quarter of a game

Speaker 2 and lost because of fatigue, which, you know, you see this happen in fights and boxing and, well, you see it happen in every sport, you know, sort of,

Speaker 2 you know, overutilizing that athlete during their performance time and not not knowing, hey, when do I back off of them, give them a chance to recover in real time, and then put them back out on the field.

Speaker 2 And I'd love to talk a little bit about that. And then I want to go deep down the rabbit hole on some of this stuff.

Speaker 1 Yeah. And I mean, it's, you know, it's really, I think having, and this is what WOOP has done so brilliantly is, you know, understanding capacity going into a match, right?

Speaker 1 So lots of factors are going to influence my,

Speaker 1 how capable I am today to be able to, you know, handle the demands of a match. So you've got kind of that baseline readiness level.

Speaker 1 So measuring and quantifying that is kind of table stakes at this point, right? You know, for the most part, we have access to that information if we need it. I think where

Speaker 1 we could go, I think, to the next level, and I think a lot actually what we were experimenting with is looking at things like EPOC, for example, excess post-oxygen consumption to understand, you know, when do I get to that place where if I keep going, I'm going to have

Speaker 1 my quality is going to begin to diminish.

Speaker 1 And what you need to do is you need to watch the data in real time to understand understand when they start to reach that threshold, pull them off, let them recruit.

Speaker 2 So how are you measuring that threshold? I mean, and for those people that don't know what Epoch is, can we just get a little explanation of what he's talking about?

Speaker 1 Yeah, so it's just, it's, it's basically when you are finished an effort, basically how much oxygen you can consume.

Speaker 1 Most of the time. Not VO2 max.
Not VO2 max, right? So this is, this is a little bit different.

Speaker 1 And when you get to a point where

Speaker 1 your quality will just diminish, right? You're going to basically adapt to a lower level of functioning.

Speaker 1 when you get to a point where you are asking where your body can no longer meet the demands, right? And that's where, you know, fatigue starts to set in. You can't run as fast.

Speaker 1 You can't, your decisions start to wane.

Speaker 1 You know, your body starts to not shut down, but it just is not operating as efficiently, right?

Speaker 1 So you know, in the first quarter of a game versus the fourth quarter, you know, there's a difference, right? And in the quality.

Speaker 1 But I think that's really what I was trying to tap is how do we maintain a really high level of quality, quality over the course of the game? It doesn't mean we're always going to win, right?

Speaker 1 If a team is more talented than we are, but I really was interested in putting ourselves in a position where we were never losing games

Speaker 1 we should win, right?

Speaker 2 Number one.

Speaker 1 And I didn't want to lose because of fatigue. Right.

Speaker 1 So that's really what I was trying to solve with this 24-7 picture and with the technology that we were using to understand how athletes were adapting in the moment to the load that was happening.

Speaker 2 And how were you doing that in real time back then?

Speaker 1 So we had a computer that basically was looking at training effect. So, you know, in real time on the sideline.
Okay. And we were monitoring epoch, heart rate, heart variability, everything.

Speaker 2 But how? Was there something on the end? Chest wrap.

Speaker 1 And we had blue. Yeah, we had four Bluetooth hubs that were surrounding the field.

Speaker 2 And they would let you do this. I mean, you just didn't say anything.

Speaker 1 I just went to my board and I was like, okay, I want to get this technology. It's going to help keep us healthy and safe.
But really, and that's, that's really what I was asking.

Speaker 2 That's amazing. I'm such a huge fan of that.
Right.

Speaker 1 Well, we were just, you know, I, I, I love, love, you know, I mean,

Speaker 2 you know,

Speaker 1 this, of course, yeah, it was about a competitive advantage, but, you know, I wanted to keep my athletes healthy and safe, right?

Speaker 1 We know that availability is going to predict 80% of team outcomes, right? Just literally, how available are you to train and compete? And, you know, to me, this was a way that we could understand,

Speaker 1 you know, how athletes cope with load. We could understand, you know, really how to just keep them safe over the course of the season.
Yeah.

Speaker 1 So I think for me, it was just part of the job.

Speaker 2 Yeah, I think it's a very nouvea turn to start talking about readiness.

Speaker 2 Like, you know, I was an amateur triathlete, you know, years ago, so I never was at a professional level, but my judgment of whether or not I was ready was just basically how I felt. Yeah.

Speaker 2 You know, how did I feel climbing on the bike? How did I feel when I started out a run? And sometimes it was predictive.

Speaker 2 But really often I was, I was shocked by how unprepared I was.

Speaker 2 And, you know, now that I've been deep down the rabbit hole of data, I think if you were to distill distill all of superhuman performance down to a single metric in terms of its impact, I mean, would you agree that that would be sleep?

Speaker 2 Or would you say it's a combination of

Speaker 1 both things? It's probably, you know, Windrid et al. just published a paper in January of 2024 that basically looked at all the different markers of sleep.

Speaker 1 And what they found is that sleep regularity was a bigger predictor of all-cause mortality than sleep duration. Now, it doesn't mean that time in bed doesn't matter.
It does.

Speaker 1 but sleep regularity, I think, might actually trump how much time you're spending in bed. Now, you need to get

Speaker 2 when you say regularity, you mean same time going to bed, same sleep routine.

Speaker 1 Yeah, so onset and offset. So, if you think about your sleep, when you go to bed and when you wake up, and you want to make that as consistent as possible.
Wow.

Speaker 1 And this is, you know, I've been tracking this for a long time on WOOP. And, you know, it was a paper came out in 2017 by Andrew Phillips,

Speaker 1 who was at Harvard and did a study with Harvard students. And what he saw looking at, you know, he had their

Speaker 1 kind of

Speaker 1 their daily sleep habits, you know, prior to the study and then during the study. And basically what he saw is that the one thing that predicted GPA was sleepwake regularity.

Speaker 2 No way. Yeah.
It predicted GPA.

Speaker 1 It predicted GPA.

Speaker 2 Wow. Yeah.
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Speaker 1 So, you know, I started because at the time I was working with a lot of athletes. You know, this is when WOOP was deep into NC2A

Speaker 1 and professional teams. And so I was tracking all sorts of data.
And after I read this paper, I I started manually tracking kind of onset and offset to see what I could find in the data.

Speaker 1 And sure enough, you know, sleep regularity kept popping up.

Speaker 2 I mean, I've seen it.

Speaker 1 Being predictive. Yeah.

Speaker 1 And then so we started just basically running some experiments, so some prospective research, like just seeing, you know, trying to run some interventions to kind of see and, you know, in more experimental kind of format to see, you know, what is the role of sleepwake timing,

Speaker 1 you know, in in terms of resilience of some of these other psychological markers? And, you know, does it actually predict physio, you know, in any of these physiological markers? And sure enough,

Speaker 1 yes to both those things. Really? Yes.

Speaker 2 So, so if I was going to develop a good sleep routine, good, what I call good sleep hygiene,

Speaker 2 not in terms of being clean, but just hygiene in terms of your routine, it's amazing how I did a sleep challenge a few months ago with Woop. Yeah.

Speaker 2 And we, we had thousands of people that participated in it.

Speaker 2 And what was astounding to me was that when I would get people on these Zoom groups and we would open up a dialogue of questions, most people actually had no kind of consciousness about sleep,

Speaker 2 no sleep routine at all. And if I asked them about exercise, they had a routine.
About getting their kids to school, they had a routine. Nutrition dialed in.
Nutrition dialed in, like

Speaker 2 their job, they had a routine for work.

Speaker 2 I'm like, what's your sleep routine? I'm like, well, I go to bed. And I'm like, well, what time do you go to bed? Well, when I'm tired or when

Speaker 2 it's the end of the day or the night. It's an afterthought.
And it was astounding to me

Speaker 2 the paucity of

Speaker 2 realization that people had about the importance of sleep. And so we just did something very basic.
And

Speaker 2 we got a baseline and a couple thousand people and we ran this sleep challenge. It was a three-day sleep challenge.
And we did simple things like, okay, we're going to develop a routine,

Speaker 2 not eating two hours before bedtime, cooling the temperature of the room down, darkening the room, taught them a breathwork technique, you know, to do while they were in bed, no screen time in bed, the things that I knew that everybody could do without spending any money or buying any other fancy equipment other than the WOOP to track it.

Speaker 2 And what was pretty interesting was we saw, again, anecdotal in this big group, but about an 18%

Speaker 2 increase in their sleep score, um, which obviously led to improved, um, you know, recovery and strain, reduced strain, improved recovery. And

Speaker 2 because we just brought their level of consciousness about sleep, you know, to the forefront. Yeah.

Speaker 2 And it's interesting because I, you know, I open up our, we still, I'm still in this whoop group, and

Speaker 2 my sleep score gets uploaded in there every day. So I'm like,

Speaker 2 so now I'm like stressed about sleep because I'm like, heck, it's my group. So if my sleep score is crap, you know, then people are going to be like, ah, he's a charlatan.

Speaker 2 So I do make sure that I go to sleep, you know, routinely at the same time. Yeah.
But the one thing that we were not

Speaker 2 tracking was the routine, like bed at 10 p.m. or bed at nine p.m.
Yeah, the consistency. I mean, the consistency.

Speaker 2 So, what you're saying is that is as if not maybe one of the most important factors for people to try to control.

Speaker 1 I think it's the biggest rock.

Speaker 2 That's a big statement.

Speaker 1 It is, yeah. And I,

Speaker 1 and I say that because I think when we, when we consider the circadian system,

Speaker 1 and

Speaker 1 when you, when you think about the circadian system, like there isn't a cell, cell, tissue, or organ that it doesn't touch. So when you're, you know, it's, it's the regulator.
Yeah.

Speaker 1 And so when you think about human health and functioning, and if you're not thinking about circadian rhythms kind of more broadly and certainly thinking about your sleep wake timing, you're just kind of missing a big piece of the puzzle.

Speaker 1 And I think we think about all these other things, right?

Speaker 1 And all those other things are important and we need to do them. But when our foundation is

Speaker 1 unstable, we're just kind of layering inefficiency on top of inefficiency. Right.

Speaker 1 So if we really want to optimize our health or if we just want to fix our health, the place to start is circadian alignment.

Speaker 1 Circadian misalignment, in my view, is the biggest problem in modern society.

Speaker 2 Because we're fighting the natural

Speaker 2 cycle.

Speaker 1 Yeah. I mean, we have access to artificial light 24-7.
We have access to food 24-7.

Speaker 1 And

Speaker 2 temperature regulations. Yeah, everything.
Yeah.

Speaker 1 I mean, we just, yeah, we're in like climate controlled environments all the time, right? So we just, we haven't adapted to

Speaker 1 blue light after the sun sets, for example. Right.
Right. We haven't adapted to eating, you know, huge meals after the sun goes down, like right before we go to bed.

Speaker 1 So a lot of these things, you know, we're just, we're kind of fighting our internal preferences, right?

Speaker 1 Every like all of the clocks in our body want to do things at certain times. Right.
And when we bypass those internal preferences, we cause

Speaker 1 a lot of miscommunication.

Speaker 2 Misregulation, sure.

Speaker 1 You know, the cells don't communicate as effectively, right? And we know that cellular miscommunication is the basis for aging and disease.

Speaker 2 You know, interestingly, I saw there was a sleep physician. I forget his name.
He's got the long blonde hair, but he was on Humerman. Oh, Matthew Walker?

Speaker 1 Dr.

Speaker 2 Matthew Walker. Yeah.
Amazing.

Speaker 2 One of the statistics that he put forward, and I don't want to misquote it, so I'm going to paraphrase it, which was was astounding to me, was about daylight savings time and about the increase in cardiovascular disease

Speaker 2 events and stroke,

Speaker 2 and the decrease in the concomitant decrease in cardiovascular events. So, when we lost an hour of sleep,

Speaker 2 there was a corresponding spike repeatedly in cardiovascular events. And when we actually gained an hour of sleep, there was a corresponding decrease.

Speaker 2 And this happened over and over and over on the daylight savings times

Speaker 2 each year. And I mean, that just kind of shocked me.
Yeah.

Speaker 1 When people are vulnerable already, right? Sleep is just going to throw you over the edge, right? Yeah, you're right on that edge. And sleep regularity, right?

Speaker 1 Like missed time sleep or, you know, changes in your typical sleep wake time just really throw your system for a loop. And I think that, that, that study is that.

Speaker 2 I think it's becoming so much more, you know, mainstream and in vogue for people to really pay attention to their sleep.

Speaker 2 You know, I know Brian Johnson talks about it being your, you know, superpower, the biggest superpower that he's discovered in his journey with Blueprint.

Speaker 2 And I'm a big believer in that. I mean, a few years ago, I stopped,

Speaker 2 I started scheduling all of my meetings and travel around sleep and exercise. Nice.
And what a dramatic difference it has made in my psyche. Yeah.

Speaker 2 Just.

Speaker 2 I don't know how to sort of paraphrase it, but just like my level of happiness and contentness and the readiness I have for meetings and preparedness for podcasts.

Speaker 2 I mean, that's why I put the podcast here in my home.

Speaker 1 And just what you're talking about is circadian alignment. Yeah.

Speaker 1 You know, so when you look at, you know, the consequences of circadian misalignment, it's, you know, it's increases in cancer risk, it's cardiovascular disease, it's diabetes, it's obesity, mood disorders,

Speaker 1 psychiatric disorders, right? Like there is not a mental health issue that circadian disruption doesn't touch. 100% of mental health issues will have some sort of circadian disruption.
No question.

Speaker 2 And I think sleep is just always the thing that we sacrifice, right? It's the easiest thing to forego, right?

Speaker 2 So, you know, we didn't have time to finish a project, so we stay up late at night and go to bed, and then we still have to get to work in the morning, or we just decide that

Speaker 2 we'd rather, you know, we're going to a destination, we want to have a whole day when we get there, so we're just going to take the really, really, really early flight, you know.

Speaker 2 And so now we're getting up at three in the morning to make a 5:30 flight.

Speaker 2 And so it's always the thing that I think we push around in our life, right? And I think it should be the thing that is the state.

Speaker 2 Yeah, the constant.

Speaker 2 I couldn't, couldn't agree with you more. You know, we had a really interesting conversation here in the unit before the podcast about some of the psychiatric impacts on

Speaker 2 performance.

Speaker 2 And you have a PhD in psychology.

Speaker 2 And I think it's a really interesting

Speaker 2 approach to take psychology and apply it to physical performance. Because the way that modern medicine, in my opinion, looks at the human body is that this is completely separate from this, right?

Speaker 2 Like somehow there's no connection here at the neck.

Speaker 2 We treat psychiatric disorders not as gut issues. We We don't treat gut issues as psychiatric issues.

Speaker 2 And so we had a really interesting discussion about the psychiatric impact of thought and perceived stress on performance.

Speaker 1 Could you give us a little yeah yeah so I'm a psychophysiologist so I started kind of with physiology and

Speaker 1 expanded into psychology really because of you know so a psychophysiologist basically

Speaker 1 you know, as a psychologist, I look at, you know, psychological processes and basically the interrelationships between your psychological processes and physiological responses, and vice versa.

Speaker 1 So, understanding kind of this connection, in my view, is so critical, right? When you have studies that just look at the physiology, but we don't know how someone's,

Speaker 1 or just the psychology, we don't know how someone slept, their sleep patterns, like we're just missing a piece of the puzzle.

Speaker 1 Same sort of thing.

Speaker 1 If we're looking at some of these physiological processes, but don't have any of any psychological context in terms of their psychological functioning, again, we're probably missing a piece of the puzzle.

Speaker 1 So, you know, from my perspective, you know, merging these two domains is so essential.

Speaker 1 And that's really where wearable technology has enabled us to basically run these psychological kind of experiments or, you know, include psychological measures while collecting all of this physiological data.

Speaker 1 So

Speaker 1 we ran a huge study looking at, you know, blood pressure, stress, and sleep.

Speaker 1 And, you know, in that, in the survey, we asked folks their perceptions of their day to the degree that they thought their day was threatening versus challenging.

Speaker 1 So we asked them at the end of the day. We also asked them lots of sleep anxiety questions.

Speaker 2 Sounds threatening.

Speaker 1 Yeah, is your day threatening? You know, like, yeah.

Speaker 1 And what we saw was really interesting. So folks who perceived their day as really challenging actually had lower blood pressure as measured by our stress monitor, which is not surprising.
Wow.

Speaker 1 And

Speaker 1 had better night sleep the prior night.

Speaker 1 So I think what that tapped was, you know, feelings of self-efficacy. So feeling like you have the skills and resources to tackle tomorrow are going to help you sleep better.

Speaker 1 Your preparedness kind of going into the day is going to help you sleep better. Right.
So all of these feelings of challenge.

Speaker 1 But what was really interesting is, is we, our hypothesis was that people who perceive

Speaker 1 challenge are going to have lower stress.

Speaker 2 Wow. I love that.
I always,

Speaker 2 but they didn't. Oh, they didn't.
So I always say if your morning's hard, your day will be easy.

Speaker 1 So on our stress monitor, which is a scale of zero to three, and it's taking in heart rate and heart rate variability continuously, they registered.

Speaker 1 If you perceive the day as challenging, okay, you're prepared. You actually register higher on the stress scale.

Speaker 2 Wow, because you feel prepared for the stress?

Speaker 1 I think you're just mobilizing energy. You're like, you're excited about your day.
And this goes back, I think, to the thesis that stress is not bad.

Speaker 1 Right. Stress is a gift, right?

Speaker 2 It gives us energy. Hermesis is a, you stress the body.

Speaker 2 It improves by strength. It's adaptive.

Speaker 1 It's adaptive.

Speaker 1 But, and then then, conversely, when people perceive their day as threatening, so at the end of the day, they perceived as threatening, actually, their prior night's sleep was worse.

Speaker 1 Okay, so they kind of knew going into the day that they were not excited about it, and that somehow impacted their sleep.

Speaker 1 And on the stress monitor, their stress was actually lower, but their blood pressure was higher.

Speaker 1 So, I think what's happening is almost like this paralysis, right?

Speaker 1 When we perceive something as stressing, we don't move as much, we're not as energized or energetic, or you know, we're not using our brain as much, or we're not excited as excited about the day.

Speaker 1 Right.

Speaker 1 So, you know, I think how, you know, what I take from this study is obviously how we frame our day is really important.

Speaker 1 And just understanding, I think, the role of self-efficacy, like feeling like we have the skills and resources to tackle our day, we've got some element of purpose, right?

Speaker 1 I think it taps purpose as well. Like, do I have, you know, is tomorrow going to be meaningful? Is it going to be, you know, fulfill my values, right?

Speaker 1 And

Speaker 1 that has a real adaptive impact on

Speaker 1 our physiology.

Speaker 1 Um, so it's pretty exciting, pretty cool to see.

Speaker 2 That's very interesting. You know, I often think, as, you know, as much of a big data person as I am, I also think that there's, you know, and this was 35,000 people.

Speaker 2 35,000. Wow, that's a huge sample study.
See, here we go back down. You know, you're reinforcing my belief in, again, in big data.

Speaker 2 I mean, I think that big data is going to revolutionize modern medicine in a way that,

Speaker 2 in my opinion, is going to be catastrophic for modern medicine.

Speaker 2 And the reason why I say that is that we will no longer be beholden to the randomized clinical trial, the isolated clinical trial that we're extrapolating out to a large population.

Speaker 2 We're going to have big data on human beings in real settings where everything, you know, is controlled.

Speaker 2 You know, we talked about a sleep study, for example, you know, five people go in or eight people go into the University of Miami and they sleep on a, you know, a...

Speaker 2 plastic cot and some dude's looking at them through a two-way mirror and they got electrodes all over their head and that's supposed to somehow be representative of every single night of every sleep Yeah, every single night of every sleep.

Speaker 2 And they're like, you know, REM starts here and, you know, deep sleep starts here.

Speaker 2 But, you know, rather than like what WOOP can do, which is take a giant population of people and examine hydration and

Speaker 2 their environment and their sleep and their recovery and their strength in their own natural environment, which is where, you know, we're human beings behave in communities.

Speaker 2 We don't behave in isolation. I don't think that we should be studied in isolation.
I don't think that ourselves should be studied in isolation. Sometimes when we do that and we extrapolate out

Speaker 2 data from that, it ends up being very detrimental.

Speaker 2 And what's happened historically, and I talk about this a lot, is, you know, these 10 year long randomized clinical trials to get, you know, a drug or a synthetic or pharmaceutical approved sometimes very often have a very,

Speaker 2 a very narrow hypothesis that you're trying to prove. And if they prove that, and then it results in a treatment, you know, a drug, pharmaceutical, chemical, synthetic, what have you.

Speaker 2 And then we get 10 years more population data and we realize we made a major mistake. But now we're 20 years down the road.

Speaker 2 I think that timeframe is being compressed to 30, 60, 90, 120 days now because of things like wearables. It has the potential to, you know, so much data.
Yeah.

Speaker 2 What, what are, so

Speaker 2 as good as big data is, you can also get paralysis of analysis, right? It's like trying to buy a stock and you got 50 different stock charts and eventually you just freeze.

Speaker 2 And I think sometimes when people are approaching wearables, like you can go pretty deep down the rabbit hole and whoop, right?

Speaker 2 As much as you, as deep as you you want to go, you can go. So

Speaker 2 for the non-professional athlete, you know, for someone that is genuinely interested in optimizing their health, like where do they start?

Speaker 2 What are the key, like one, two, three metrics that you should be measuring? And then when they get that data, what kind of actionable steps could they take?

Speaker 1 Yeah. I mean, I think the metrics that I pay most attention to, sleep consistency, which we talked about.

Speaker 2 I mean, I tend to be very consistent with my sleep, but it's one of the things that we didn't actually track.

Speaker 1 We see that, you know, after like a few, so the average, so healthy user bias, right? We have the folks who choose to be on WOOP usually are like, all right, I want to be healthier.

Speaker 1 I want to sleep better. I want to understand how to recover.
I want to build strain. You know, they're pretty motivated.
Probably.

Speaker 2 I want to build strain.

Speaker 1 You know, they're probably pretty motivated, right? So, you know, just.

Speaker 1 understanding that we've got kind of this healthy user bias, which is what I'm going to say, I think make, I think that fact makes what I'm going to say even more profound: is that when you look at sleep consistency, the average sleep consistency, which is on a scale of zero to 100, right?

Speaker 1 The more consistent your sleep, the higher your sleep consistency score. So, 100 would be, you know, very consistent sleep onset/offset.

Speaker 1 We take the average of your last four nights compared to today, and we give you a percentage. So, 100% would be perfect, you know, sleep-wake time regularity.

Speaker 2 So, you went and you went to bed at 10, you got up at six.

Speaker 1 Yeah, and you did that for four days straight. Okay, so you'd be have a perfect score.

Speaker 1 So, on our platform, the average sleep consistency of our members is 66%.

Speaker 2 Wow.

Speaker 2 Which solid D.

Speaker 1 So a solid D, right? So to get 85%, you have to have about 45 minutes of sleep wake variability on either end. So these folks are probably at two and a half.
On average, our members are probably

Speaker 1 varying their sleep

Speaker 1 about two and a half hours.

Speaker 2 Two and a half hours, you mean in their bedtime?

Speaker 2 Meaning 10 p.m. to 12:30 in the morning.

Speaker 1 So basically, you know, they're going to bed at nine one night and then waking up eight the next day. And then the next day, they go to bed at 11.30, they wake up at six.

Speaker 1 You know, so there's a lot of variability, right? When you're at that 66%.

Speaker 1 So what we see in the healthiest population, okay, so collegiate athletes, 18 years old to 23,

Speaker 1 after just one hour, of sleepwake variability, we see a degradation in heart rate variability and resting heart rate.

Speaker 1 wow so you can just imagine as you age you become way more sensitive right wow just a single hour just one hour of variability we see declines in HRV and increases in resting heart rate

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Speaker 1 So,

Speaker 1 we have a lot more analysis to do across different populations, but I think this gives us a sense of, wow, okay, after an hour, you know, we start to see declines.

Speaker 1 And we know heart rate variability, resting heart rate, you know, kind of ladder up to your readiness, just generally, and your overall health. And so sleepwake variability matters.

Speaker 1 And we've seen, you know, sleepwake, we did a study

Speaker 1 that looked at basically COVID.

Speaker 1 So it was the three months prior to COVID. We had all of the baseline data, so all the physiological data, and 20,000 people basically took our survey, which assessed their mental health.

Speaker 1 So basically right after lockdown, we sent this survey out. Over the course of three months, we're collecting this mental health data.
They send it back to us.

Speaker 1 The one behavior that predicted mental health resilience, okay, was sleepwake variability.

Speaker 2 Wow. Dude, I am going to go down the rabbit hole of the sleep confusion.

Speaker 2 I mean, I knew it was important, but like, you're like blowing me away with this.

Speaker 1 I think, and then we did a study with a thousand paratroopers in Army, Alaska, and this is an exploratory study.

Speaker 1 But again, we saw sleepwake consistency bubble up to being predictive of psychological functioning, workplace resilience.

Speaker 2 It's hard for those guys to be controlled.

Speaker 1 So hard, right? Yeah.

Speaker 1 But the ones that, the more consistent they were, the better workplace resilience, the better they could handle off-tempo, the better, you know, the better, the more positive their social networks, more control they felt.

Speaker 1 Wow.

Speaker 1 And, and then just most recently, this study is

Speaker 1 is in review right now, but we looked at four behaviors, four core behaviors. We looked at viewing morning sunlight, which I'm going to talk about in a second.

Speaker 1 Viewing morning sunlight, zone two training, breath work, and time-restricted eating.

Speaker 1 So the folks who did those four behaviors, this was a quasi-experimental design. So we had basically the four weeks of the challenge, and we could compare that to the data.
the four weeks prior.

Speaker 1 And we also had a match control. And this was 38,000 people.
So we had a match control of 38,000 that matched the challenge participants. Wow.

Speaker 1 And basically, we saw that the folks who participated in this challenge and did these four behaviors improved their sleepwake consistency and then in turn improved statistically meaningful, meaningfully improved their cardiorespiratory fitness and their parasympathetic activity by just engaging in these four

Speaker 2 cardi behaviors.

Speaker 2 Yeah. Yeah.
So let's, what are the four again?

Speaker 1 I want to make sure it was viewing morning sunlight, right? So when we talk about sleep.

Speaker 2 Okay.

Speaker 1 yeah exactly so when we talk about sleep and for folks who you know are like all right i i want to improve my sleep

Speaker 1 a lot of the sleep industry is going to just say spend more time in bed cold dark quiet those are all really important yes but in order to really improve your sleep you need to stabilize when you go to bed and when you wake up and to do that you have to

Speaker 1 tell your body when it needs to release melatonin, right? Which is going to signal to your body that it's dark and it's time to be asleep.

Speaker 1 But to do that, that, you need to view morning sunlight.

Speaker 2 Yeah,

Speaker 1 I'm so you got to set your set your alarm, you know, at for a time that you can adhere to.

Speaker 1 Get up at that time within 20 minutes, get outside, view the natural light for five minutes, 10 minutes, depending on how cloudy it is. You might need to spend a little bit more time outside.

Speaker 1 But that is the best way to improve your sleep.

Speaker 2 Wow.

Speaker 1 And get to that kind of sleep regularity.

Speaker 2 That's, I mean, that's one of my drugs of choice. You know, I have the

Speaker 2 right outside. So the sun is on the east side of, you know, my building.

Speaker 1 I mean, your setup here is just, you got the sun set.

Speaker 2 The sun sets. Sunrise.
You just walk across the sun.

Speaker 2 Yeah. But, but I love it because,

Speaker 2 you know, I'll go out there and I'll also just do some horizon gazing. So

Speaker 1 the generative vision, which immediately drops your heart rate, increases your heart rate variability.

Speaker 2 You know, drops your heart rate. And I'll just do.
three rounds of 30 breaths. Don't put a lot of stress on myself.

Speaker 2 I usually just try to expose as much of my skin to sunlight, which my neighbors don't like. They love it, yeah.
Whatever.

Speaker 2 Not fully in the birthday suit, but I, you know, I'm down in my bathing suit and I'll, and I'll just go out and I'll sit on the chair, I'll horizon gaze, do three rounds of 30 breaths.

Speaker 2 I'll take in the morning sunlight. Now I'll let that sun kind of warm my skin up.
It feels amazing.

Speaker 2 Usually, you know, at first light, there's no real UVA or UVB for about the first 45 minutes. You get healthy blue light, not like the blue light we get from our screens.
Exactly. And,

Speaker 2 you know, it really does set my, my day.

Speaker 2 And, you know, again, I keep shouting out to Hugh Roman, but I was also watching a podcast of his where you actually talked about the importance of taking in this light and your effect on your sleep that night.

Speaker 2 And I do notice

Speaker 2 when I am consistently, you know, viewing sunlight and doing breath work

Speaker 2 and allowing the sun to hit my skin.

Speaker 2 And sometimes I'll even go down to the park down here and ground at the same time. You do those.
those few things.

Speaker 2 I mean, touch the surface of the earth, let the sun hit your skin, view the morning light, do a little breath work, work, cost you absolutely zero. I just don't think people realize how profound

Speaker 2 of an impact it is.

Speaker 1 And I think like that's the message.

Speaker 2 Like bottle it up and patent it and then charge it and write it as a prescription.

Speaker 1 I know, I know.

Speaker 1 But that's the problem. I think people want a quick fix or they, or they want just take a pill.
Like, you know, you, you, you cannot beat the natural environment. Right.

Speaker 1 You know, like you, you, we need, we need natural light like so desperately. Our body is craving it.
Oh, we're photovoltaic beacons for sure.

Speaker 2 I mean, you know, when we we look at these red light beds, you know, these fancy red light beds,

Speaker 2 all they're essentially doing is mimicking the beneficial wavelengths from the sun. I mean, they're emitting the UVA, UVB, the damaging rays, but

Speaker 2 they're taking in that photovoltaic energy that our cells need.

Speaker 2 And there's an enormous body of evidence that exposing your skin to sunlight, you know, my opinion is that we're not getting enough sun. Not that we're getting too much sun.

Speaker 2 I mean, you look at the levels of clinical deficiency in vitamin D3, I mean, 50% of the world's population, darker-complexed populations, African-Americans, Latinos, even more.

Speaker 1 I mean, mental health issues, clearly. I mean,

Speaker 1 you know, people who are spending more time during the day in the natural light are going to sleep better. You know, like, it just has this like virtuous cycle that's funny.

Speaker 2 The whole reason why I live in Miami right now is I went to grad school in Chicago and I lived there for six years downtown. And Chicago is a great city at that time.
And

Speaker 2 just clean, friendly. I lived in the South Loop

Speaker 2 and I love Chicago. I learned to believe in like

Speaker 2 live music there. It's had a great live music scene.
But by the middle of the winter, everyone had seasonal affective disorder. Yeah.
Like everybody was in a bad mood.

Speaker 2 And all everybody wanted to do was just drink beer and eat pizza and stay inside.

Speaker 2 And

Speaker 2 I remember the feeling six years in a row of that first like Indian summer day in the spring where.

Speaker 2 you could actually go outside you could actually open your windows and you could feel the energy of the whole city change yeah right um now i was there when like jordan and pip and rodman were playing for the bulls it was a great it was really a great time in Chicago.

Speaker 2 But

Speaker 2 I just remember those, you know, they would have jazz in the park and like the whole city would come alive.

Speaker 2 But there were three or four months there where absolutely your mood, your emotional state, even, even like your memory, the level of fatigue,

Speaker 2 you know, you would put on a little bit of weight. You would just be so lethargic because you wouldn't see the sun for months.
Yeah.

Speaker 2 And

Speaker 2 so now that I live here, I never feel like that. Yeah.
You know, just having that.

Speaker 1 It's easier down here. But I can say, you know, as someone who's lived in Maine and, you know, I live in Massachusetts, like my data is better in the winter

Speaker 1 because

Speaker 1 I just, I can train harder, I think, just because I think like the hot weather reduces your capacity. You know, like I can't quite push probably as hard.
I think that's what's at play.

Speaker 1 And I definitely sleep a little bit longer in the winter, which we're supposed to do, right? We're supposed to actually adapt to the seasons.

Speaker 2 Right.

Speaker 1 But that said, I spend as much time outside in the winter as I do in the summer.

Speaker 1 So do I.

Speaker 1 Like I'm, you know, but so I think that is actually the solution for people who are in, you know, these more northern climates who, you know, it's, it's, yeah, it's maybe not as comfortable, but right.

Speaker 1 But I feel again, it's a hormetic stress, right?

Speaker 2 Yeah. You got to tell grandma not to go outside.
It's too hot, not to go outside too cold, just to lay down, to relax, to rest, you know, to eat at the first pang of hunger.

Speaker 2 I mean, these are collapsing our natural defense mechanisms.

Speaker 1 Kids don't need to be buttoned up to the T, you know, like the clothes. You know, like it's okay to cold on your skin, you know, for a little bit.

Speaker 1 Obviously, you have to be safe, but, you know, but or heat on your skin.

Speaker 1 Or heat on your skin, you know, like, oh, yeah, those, those, to your point, those stressors, I think, are really important, right?

Speaker 1 And, and, um, you know, and we need to give our bodies a chance to adapt to that stress because if we, when we adapt to it, that we grow, we get stronger.

Speaker 2 I totally agree. What, what are, what are some of the really exciting, like inspiring things right now for you that are going on at WOOP or going on with, you know, big data sets?

Speaker 2 Like, where, where is your energy going right now? Where is your curiosity taking you with big data?

Speaker 1 Yeah, I mean, I really want to help women understand how to have and maintain a healthy period.

Speaker 2 Wow.

Speaker 1 That is massive. You know, like I, I just, you know, it's one of those things where,

Speaker 1 you know, I, I feel like I've unlocked a lot for myself in this area. And

Speaker 1 we

Speaker 1 are seeing really exciting things in the data.

Speaker 1 And, you know, I have a daughter and how old's your daughter? She's She's 16.

Speaker 2 Oh, awesome. Yeah.

Speaker 1 And it just, yeah, just, you know, being around, you know, her and her friends and just kind of seeing like all the confusion and noise that exists around that.

Speaker 1 And, and I think too, like the desire to, you know, have a natural period and not be on hormonal birth control.

Speaker 1 Like, you know, there's like a real change, I think, in terms of it doesn't mean that you're not a feminist, right? If you're having a natural period, you're being a great.

Speaker 1 I think people recognize, oh, okay, you know, natural period is probably the healthier path, potentially.

Speaker 2 Natural period probably being the operative term there.

Speaker 1 And not for everyone, you know, and I'm not demonizing hormonal birth control at all. I'm just saying that

Speaker 1 the default shouldn't be, doesn't have to be hormonal control. Just because it's inconvenient.
Because what happens, it masks symptoms, right?

Speaker 1 When we take hormonal birth control and, you know, and in the way that,

Speaker 1 you know, primary care physicians are like approaching this, I think we need like a whole revamp in that area. So, just in terms of what I'm passionate about, like, you know, I just, I really want

Speaker 1 the time.

Speaker 1 I want practitioners to be able to have a bit more time to have conversations with young women around what their options are.

Speaker 1 You know, and I think that's where technology can step in and really help you understand when you're ovulating, when your fertile window is, so you can be smart about when you have sex and when you don't have sex and the type of protection that you need

Speaker 1 so you can maintain a natural period and you can get all the benefits of those fluctuations and you can see when you might be

Speaker 1 underfueling or overfueling or you know not hydrating enough or overtraining or under training, you know, that is going to manifest.

Speaker 2 Give you that kind of data.

Speaker 1 Yeah. I mean, we're getting there, you know, but

Speaker 2 this is the promise.

Speaker 1 This is, this is, I think, helping people understand

Speaker 1 how to use their period as a signal and then be able to modify their behaviors to keep themselves in the healthiest possible range to me is the future.

Speaker 1 And we can, I think, delay the onset of carry menopause.

Speaker 2 I think we're not seeing all kinds of things.

Speaker 1 Yeah, I mean, all of these things that I think that when we understand how to apply our effort, right? And how you respond to certain interventions is going to be different than me.

Speaker 1 And that's, again, I think the promise of technology. It is me against me.
Right. Right.

Speaker 1 And that's where a lot of these normative values we were talking about, you know, blood panels and hormonal panels and, you know, what is good for, you know, that girl, it might not be good for me.

Speaker 2 I totally agree with you. It's like HRV, right? You know, people compare theirs to other people.
And I'm like, well, you should really develop a baseline and start to see what's improving or

Speaker 2 making yours worse.

Speaker 1 Exactly. And your genetics is going to establish your baseline too, right?

Speaker 1 Like, just because I have maybe, you know, my resting heart rate is 50 beats per minute and my doctor is like, oh, God, you're so healthy. But maybe for me, you know, that's just because of genetics.

Speaker 1 So when I go to the doctor and they say my heartbeat, my resting heart rate is 62. And for me, that's 12 beats higher than my baseline.
That's a problem. But I'll go to the doctor.

Speaker 1 They'll be like, oh, you're so fit and healthy.

Speaker 1 I'm like, no, right.

Speaker 1 And that's, I think that is another promise of like just this longitudinal data is that we can understand our own baseline and understand what is good for me, not just these referent values that, you know,

Speaker 2 who do you have? Perfectly healthy people have HRVs in the 50s and 60s. Perfectly healthy people have HRVs over 100.

Speaker 2 My son's a pro-athlete and his HRV is constantly over 100. Yeah.
Well into the hundreds. Yeah.
And

Speaker 2 my daughter's is a lot lower, but compared to, she's also very healthy, but compared to her baseline, you know, we know what helps it and hurts it, sleeps, sleeps.

Speaker 1 Exactly. And you can modify, you know, that's, that's what's so fun is like you can do your behaviors are going to support,

Speaker 1 you know, your, your kind of values or not, right?

Speaker 1 Like you're, you know, there, so I think there's an opportunity, of course, to improve your HRV through your behaviors or improve your restoration behavior.

Speaker 2 Is there really ways to, to look look at follicular ovulation and luteal phases of the menstrual cycle

Speaker 2 and menstruating within the city? It's a very clear impact. For the wearable day, really.
Oh, yeah. What kind of things are they?

Speaker 2 What kind of metrics are you tracking?

Speaker 1 Yeah. So basically, looking at the pulse shape of your heart rate, we can see how the amplitude changes over the course of a cycle.
We can tell you if

Speaker 1 that amplitude is

Speaker 1 kind of healthy range versus not.

Speaker 2 We can kind of tell if you're in perimenopause or not like you know these are things that we're going to be able to model and and detect that's amazing because you know we we also have the clinic side of our our our business and on the clinic side you know our our our clinic director is a board-certified OBA GYN she's a regenerative OBGYN Dr.

Speaker 2 Sardis she's amazing and a lot of times we see that women that have been on birth control for prolonged period of times when one of the things they use in birth control is you know SHBG the sex hormone binding globulin and And it does exactly what it sounds like it does.

Speaker 2 It's a protein basically that binds to sex hormones, mainly testosterone. And so what it does is

Speaker 2 it doesn't throw the level of their hormones off. It throws the ratio of their hormones off.
Oh, interesting. So free testosterone to testosterone, for example.

Speaker 2 And in men and women, you know, this testosterone level, even in young women, it has an impact on this urethropoietic process of the production of new red blood cells.

Speaker 2 And so we find in the vast majority of these young women that are on birth control, especially if it's SHPG, and I know there are other forms,

Speaker 2 IUDs and things, but that use this SHPG, that their testosterone levels seem to plummet.

Speaker 2 And when their testosterone and free testosterone levels are so low, they're not producing a lot of red blood cells. They become borderline anemic.

Speaker 2 Wow. But it's the kind of anemia that hides in plain sight because, you know, red blood blood cells have a range, but they're down near the bottom of the range.
Hemoglobin has a range.

Speaker 2 You know, the fluid in the red blood cell has a range, but they're down near the bottom of the range.

Speaker 2 And so when you have, you're in the lowest percentile for RBCs, then you're in the lowest percentile for hemoglobin. And these girls are just wiped out.
Wow. They're exhausted.

Speaker 2 And they never tie it back to the birth control. But when you look at a blood panel, you're like, you don't have any oxygen in your blood.
you know

Speaker 2 and as they come off and that as that protein unbinds and yeah and their levels return to normal, like their energy goes back through the roof. So it's what's really exciting to me

Speaker 2 is that,

Speaker 2 you know, using a wearable to reliably time their menstrual cycle. So like you said, they can

Speaker 2 they can have safer times to have intercourse.

Speaker 1 You can just understand what is normal fluctuation, right? Like what is abnormal fluctuation?

Speaker 2 Maybe I know why I just don't feel my cycle line. Really good right now, you know? Yeah.
Okay. It's cuckoo time, you know?

Speaker 2 And, but i mean it just it i think it's this is what again is so exciting to me and when you can apply it to a mass population especially a population that is in their own environment and i think this is the downfall the pitfall of a lot of clinical studies that have good intentions but you take people out of their normal pathic environment and assume that they behave the same way when you put them back in or you take a cell out of the body and study it in isolation you assume it's going to behave the the same when you put it back in the body.

Speaker 2 And I think nothing could be further from the truth. I think big data combined with artificial intelligence

Speaker 2 is going to absolutely lead the charge.

Speaker 1 It's just going to

Speaker 1 cut down on the guesswork.

Speaker 1 There's no need. We're getting so close to not having to guess.
Yes.

Speaker 1 You know, and that's what, like, when we take this back to like our original conversation with my athletes, like I was just, I didn't want to have to guess, right?

Speaker 1 I just wanted to be able to keep them healthy. I wanted to keep them safe.
I wanted to, you know, just be able to, you know, just, I wanted them to be able to thrive, right?

Speaker 1 And a lot of this stuff that we, that, you know, frankly

Speaker 1 is really noisy, you know, just this metro cycle. How do we actually, you know, train? Like, do we need zone two versus zone five? Or, you know, can women do zone two?

Speaker 1 You know, like, there's so much of this stuff out there that. I can't wait to answer a lot of these questions.
And we're not far from being able to do that, you know?

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Now let's get back to the Ultimate Human podcast.

Speaker 2 Does it surprise you that I work with a a lot of professional athletes

Speaker 2 in the NFL? I also sit on the board of the NFL Alumni Association Athletica. I work with a lot of professional fighters.

Speaker 2 It's pretty astounding to me how many athletes and even athletic teams are relying on just pure talent, right? Athletic ability.

Speaker 2 And, you know, okay, when you're 19, 20, 21, 22, you can just pure talent will get you through just about anything.

Speaker 2 But, and, and, you know, they're into nutrition. They've really dialed in training.

Speaker 2 I think that like strength training and position training and all, I mean, they're, yeah, they're really dialed in in the training.

Speaker 2 Yeah.

Speaker 2 But the paucity of real understanding of this type of data or the availability of data, I mean, I think still, if you were to go to most professional teams and talk about heart rate variability tracking or sleep tracking or, you know, readiness, recovery, strain, any of these metrics that were so easily available.

Speaker 2 Yeah. That could, I mean, you're way ahead of your time.
What you were doing

Speaker 2 in your collegiate guy now coaching at Princeton

Speaker 2 that you haven't even done for what, a decade? Yeah.

Speaker 2 They're not doing that. No.

Speaker 1 They're leaving so much on the table. So much on the table.

Speaker 1 And I'm in so many high-performance environments. You know, just have been over the course of the years.
Yeah. There's so much we could be doing.

Speaker 1 And a lot of the barriers, frankly, just are around trust. You know, the athletes don't trust the performance science team, you know, that to handle the data and to model the data.

Speaker 1 And it's such a shame. Yeah.

Speaker 2 Because I think very individualized, too.

Speaker 1 Like some some of them yeah they'll have their own team one guy yeah but it but that's where you know it's like if we want to manage load over the course of a season and keep athletes healthy like you need that data right and the coach needs to know how many minutes do i play this guy you know and some of the teams are doing it but I guarantee it's not as dialed in as it could be like you could be way

Speaker 2 a lot of players you know um take this into their own hands too you know like the ones that are hyper dedicated yeah yeah you know like you look at somebody like a Tom Brady that you know really took matters in hand.

Speaker 1 And he had a lot of control over, you know, in that environment, just given that he was Tom Brady.

Speaker 2 Right. Right.

Speaker 1 He, he probably had a lot of say over when he practiced, how much he practiced, you know, what his load was going to be that day. Right.

Speaker 1 But I, but I think that, that to me is kind of the missing piece in a team environment is really being able to individualize training and have that actually be part of the culture, right?

Speaker 1 How I responded to yesterday's game is going to be very different from the guy on my right and my left, right? Based on how I I slept, how I ate, you know, just how I'm managing my relationships.

Speaker 1 You know, there's a whole myriad of factors that are going to influence how I show up today. Yeah.
Right.

Speaker 1 And being able to account for that and plan a practice around that to me is like the only way to do it. And that's literally what I was doing as a coach.

Speaker 1 And one of the reasons why we were so successful is it was so individualized. And that became part of our culture.

Speaker 1 And because I think where teams go wrong is, is I think that they try to apply one model to all the athletes. Right.
And that is just not the way physiology and psychology works.

Speaker 1 Like we're so individual. Now you can have cultural norms, you have team values, like you have everyone kind of centered around this like common mission.

Speaker 1 But in terms of how you train someone and the individual protocols that each person needs, I'm sorry, it's going to be different.

Speaker 1 And if you can't create an individual performance plan for each athlete,

Speaker 1 you're going to leave something on the table.

Speaker 2 Yeah. You know, it's interesting.
You know, part of our clinical practice is we do genetic testing. Nice.
And what's becoming really exciting about genetic testing is that,

Speaker 2 you know, our genes, you know, they say they load the gun, but they don't pull the trigger. I mean, you know, epigenetics, our environment, right? It's a set point.
It's a predisposition, right?

Speaker 2 But you're not,

Speaker 2 you know,

Speaker 2 if you have the BRCA gene, you're not guaranteed to get breast cancer.

Speaker 2 If you have predisposition for, you know, early onset cognitive dysfunction, you're not guaranteed to get Alzheimer's or dementia or, you know,

Speaker 2 early, you know, memory loss. You can make behavioral changes and environmental changes that have dramatic impacts on pushing that back or even eliminating it from your life.

Speaker 2 But it's, it's astounding how, you know, I think like in early cancer screening, people are like, I just don't want to know. No, actually, you do want to know, right?

Speaker 2 You, you, you want to know as early as possible so it is the least disruptive to your life. But

Speaker 2 I feel like in general, there's a slow adoption for this type, especially the pace that big data is moving and its pace of adoption. Like people like you and I are like, dude, this is great data.

Speaker 2 You should be paying attention to this.

Speaker 2 How do you bring it more?

Speaker 2 mainstream how do you how do you improve the the adoption of it i guess prove the efficacy i mean i i

Speaker 1 I think the science is there, you know, in terms of Hare variability. It's accurate.

Speaker 2 You know, like we've got external studies that are able to

Speaker 1 validate. Yeah.
I mean, I think

Speaker 1 we are starting to know that, oh, this is a really nice proxy for my overall mental and physical and emotional health resilience profile, right? Like, I think HRV is a great proxy.

Speaker 1 Everyone, I think, recognizes heart rate, you know, resting heart rate is also a great proxy. So all these technologies are doing that pretty well.
It's like table stakes.

Speaker 1 It's not, it's pretty accurate. And our sleep, sleep staging, like all of that is getting better and better and better.
You know, our algorithms are getting better.

Speaker 1 And

Speaker 1 so I think there's a lot of insight to be derived. And I think to get people over the hump, they have to be just willing to kind of face the truth.

Speaker 1 And I think that is the, to your point, is the barrier for some folks. They're like, I don't know if I want to know, you know, or I don't know if I'm ready to make change.

Speaker 1 And so I think number one, it's people, all right, I want to make some change.

Speaker 1 And then, you know, not being intimidated by the data, but being, all right, this is going to be a tool to help me understand if what I'm doing, if the effort I'm putting forward is actually helping.

Speaker 1 Right. Right.
And I think that's, that's where we need to get people to is just like, hey, it's not about the score per se.

Speaker 1 It's about understanding if how you're applying your effort is actually working. Right.
Right. And that's really a lot of the reason.

Speaker 2 You don't really have a

Speaker 1 understanding. Yeah.
I mean, you just, you just don't know if like how you're, the effort that you're putting in is, if you're actually getting the return, right? Right.

Speaker 1 You can see your body changing maybe, and, and that's good

Speaker 1 motivation, um, but your body can change. For example, I could lose a lot of weight, lose a lot of muscle, and I can look great, but what's my scorecard internally? Yeah, right.

Speaker 1 Like, that's, that's what really matters, right? So it's getting people to recognize that, okay, whatever's going on on the outside, that's one thing. Okay.

Speaker 1 And yeah, that's a signal, like your skin health and your hair health, like all of that.

Speaker 1 Yeah, your nails and all that matters, but, but there is a scorecard internally too, that we now have insight into.

Speaker 1 And the things, the behaviors that are going to impact

Speaker 1 our ability to adapt to external stress are things for the most part that we can control. And my research is really about what is that taxonomy? What is the order of operation?

Speaker 1 How do we move the needle the most? Right.

Speaker 1 You know, and that's where like all of the research that we're doing is kind of basically distilling down the physiological and psychological variables that matter the most.

Speaker 1 When I say physiology, I mean like circadian behaviors, recovery behaviors, training behaviors, right?

Speaker 1 I kind of bucket them really loosely on the psychological side, kind of the core psychological needs, purpose, self-efficacy, control, like understanding how these variables move around our internal status and how they relate to each other, the psychological aspect and the performance aspect.

Speaker 1 How they play off one another.

Speaker 2 They're just their inner, their interconnectedness, which I think is so exciting about what you do because, you know, having a psychiatry background and then having this big data, I mean, you, you must, I mean, I'd be like a little kid if I was you.

Speaker 1 No, it is. We, we try to pre-register.
Like, so we, we try not to go in and just cherry pick, right? Like, you know, sometimes we're doing just exploratory study.

Speaker 1 We always call that out if we ever publish any of that type of exploratory research, but we pre-register an open science framework every study that we do. We follow the scientific method.

Speaker 2 Right.

Speaker 1 Right. So and we do, we do retrospective analysis, which we pre-register.
Well, we're going to look at ice baths, have some insight around that if you want to. Yeah.

Speaker 2 Yeah. Definitely.

Speaker 1 hot off the press.

Speaker 2 Please don't stop me from doing the cold plunge because I will chop this podcast off right here because it's my favorite thing. I know.
I know.

Speaker 2 She's going to

Speaker 2 be a cold plunge routine. Tiny.
A tiny bit.

Speaker 1 A tiny bit. But we could still, we could do the end of one analysis.
But

Speaker 1 yeah.

Speaker 2 But

Speaker 1 I don't even know.

Speaker 2 What were you saying?

Speaker 1 Shit, I got thinking about the ice bath.

Speaker 2 Yeah,

Speaker 2 let's go into the ice bath because when she got here today, I was actually in an ice bath. You were.
You were.

Speaker 1 Yeah.

Speaker 2 I call it my drug choice. I mean, it's just like three minutes and I go in there.
I only do it at 50, 51 degrees was what it was today. So I don't believe in the colder is better, longer is better.

Speaker 2 I think there's a place that you can take hormetic stress to the point where, you know, you're overdoing it. Yeah.
You know, not 90 minutes in a 200-degree sauna is way too much.

Speaker 2 You know, you're baking your brain.

Speaker 2 I think the really, really cold ice baths for prolonged periods of time can actually take the hormetic stress into a place that's non-beneficial. Oh, it is.

Speaker 2 But I'd love to hear what you have to say about it.

Speaker 1 Yeah. So, you know, this is not, oh, I was just talking about pre-registration.

Speaker 2 It's kind of going off. Yeah.

Speaker 1 You guys,

Speaker 1 yeah, we, you know, we really, we really try to, so basically, what Open Science Framework is and what pre-registration is, basically you put your hypotheses out in the world.

Speaker 1 You say exactly how you're going to analyze the data. You know, you just literally put everything you're going to do.
out in the world before you even look at the data.

Speaker 1 Okay. So, um, yeah.
So anyway, we want to-that's important. It's important.

Speaker 2 Yeah, so you don't have an end destination in mind, and you sort of because that's the other thing that I learned, you know, in statistics is you know, you tell me where you want to go.

Speaker 2 And I'm careful what the result is.

Speaker 1 Many people don't care what the result is. We're just agnostic.
We're looking at the data.

Speaker 2 We're trying to prove

Speaker 2 the hypothesis. Yeah.
Data. Okay.
So, moving into bursting my bubble about cold punching.

Speaker 1 Yeah. So, so, ice bath.
So, this is really interesting. So, you know, I think

Speaker 1 to this is a very, very big data set right there's lots of people on our platform who ice plunge very consistently so what we did is we bucketed the group into high fit and low fit

Speaker 1 okay so folks who are high fit we just looked at normative values so we're just you know heart rate variability resting heart rate um bmi like all that just basically kind of created yeah and just like a high fit group and a low fit group and then we looked at the frequency of their ice bath.

Speaker 1 So what's great on WOOOP is you basically can record when you start an ice bath and when you end an ice bath. So we have these really nice timestamps.
So some people forget to stop it, right?

Speaker 1 It ends up, you know, being like 12 hours. Exactly.
So those we had to throw out, obviously, because those aren't, those are not going to be accurate.

Speaker 1 But we could actually go back and tell in the data.

Speaker 1 We did this for some, but then it got. it got too much.

Speaker 1 We can actually see when it ended because there's very clear responses, physiological responses when you're in the ice bath.

Speaker 1 But anyway, we had this plenty of data in both this high-fit and lowfit group.

Speaker 2 And basically what we saw, the fitter you are,

Speaker 1 the more you ice bath, the less good it is for your recovery when you're ice bathing more than three times per week.

Speaker 2 Really?

Speaker 1 We see a diminish. We see a

Speaker 1 decline in your markers of recovery after three days

Speaker 1 of ice bath. And your ice bath is more effective on days that you are not exercising.
I think going back, exercise, of course, is a hermetic stressor as well.

Speaker 1 So you're layering on top just all the stress that's happening during the day, the stress of your workout, the stress of the ice bath, it has a deleterious effect on markers of recovery. Wow.

Speaker 1 So, but for the low-fit people,

Speaker 1 it's only beneficial.

Speaker 2 Really? And potentially

Speaker 2 low-fit people are not stressing their body

Speaker 1 as much. So they get a big return on markers of recovery from engaging in ice bath.

Speaker 2 Because right now I'll do three minutes, probably five days a week, some sometimes six days a week if i'm home um i do three minutes 50 degrees and then i um you know i dry off i warm up i do 10 12 minutes on the treadmill and then i always feel like i have an amazing workout after that a normal ice bath after the workout um because i don't want to i don't want to shut down the normal repair process but again i'm not tracking that so um this is completely anecdotal this is just how i feel yeah um and i and i sort of have this mental thing in my head where, you know, I wake up in the morning and I don't, as I exit my bathroom, there's the ice bath.

Speaker 2 And then I come down the hallway to the coffee maker and I make myself do an ice bath. Yeah.
Just because I want to do something hard. I know, I know.

Speaker 1 It's so good for that.

Speaker 2 And it doesn't get easier. Come down to the ice bath.
Maybe what I'll do is

Speaker 2 start to measure and track these and maybe back off the number of times.

Speaker 1 Yeah, but potentially, you know,

Speaker 1 again, you know, this is, is we, we have a, uh, quite a bit more to look into the data set in terms of the timing of the ice plunge relative to exercise. We don't necessarily know that.

Speaker 1 And then we need to dig into sleep as well. But the results, it looks like ice bath, regardless of when you do it, is sleep promoting,

Speaker 1 which was really neat. Yeah.
Cause I, you know, I would have said.

Speaker 2 So sleep promoting should be good for recovery. Right.
Sleep promoting is good for recovery. Yeah.

Speaker 2 And then, but the fact that the more deconditioned people, like, like, you know, there was an amazing study by Otto Warburg on multi-step oxygen therapy.

Speaker 2 And he basically took deconditioned, mainly geriatric patients. And,

Speaker 2 you know, since he couldn't put them on a treadmill and since they obviously weren't going to go outside and most of them have even a hard time walking, and what he did was he put them in a sauna and used the sauna to raise their heart rate.

Speaker 2 And while their heart rate was elevated, he ran high. concentrations of oxygen.
In the study, he did it at 50% O2 and ambient air is about 21% O2.

Speaker 2 And the amount of improvement in fitness was incredible just from marginal increases in their heart rate and exposure during that timeframe to

Speaker 2 oxygen.

Speaker 1 It mimics exercise.

Speaker 2 Mimicked exercise. So I have two elderly parents.
My father's handicapped from a scuba diving accident, fully cognitively functioned, but he has motor coordination issues.

Speaker 2 He got hit in the rear part of his brain. uh by the problem of a boat so he's had motor coordination um issues for for 30 years on on the left side of his body.

Speaker 2 And then my mother had dual knee replacements. And

Speaker 2 so she's not highly mobile. So I got them a sauna.

Speaker 2 I do a lot of other stuff. I have most cerebral lysine peptides and other things, but I got him in a sauna.
And so four days a week, they do 20 minutes in the sauna.

Speaker 2 And I run a nasal cannulus of oxygen in there. The improvement in their mood, emotional state, chattiness, if that's a measure.

Speaker 2 You know, just,

Speaker 2 you know, my, my dad says mom's memory is better. Mom says, dad's memory is better.
I mean, they're, they're a lot more active now.

Speaker 2 It's just, it's, it was astounding how this little variable made such a noticeable change in the

Speaker 1 so exciting.

Speaker 2 So, you know, there's, there's hope even for the decondition. But going back to your point of these ice baths, for

Speaker 2 decondition or what you were calling the non-fit group.

Speaker 1 I mean, it could be a way to, you you know, when I think about it as just like a way to kickstart maybe becoming more active, right? Cause all of a sudden you're like,

Speaker 2 whoop. Yeah.

Speaker 1 I mean, you know, and,

Speaker 1 you know, we're seeing it improve, you know, reducing heart rate and increasing heart rate variability, which should, in theory, increase capacity, which should give you more energy to exercise.

Speaker 1 And so it could be a way to jumpstart potentially.

Speaker 2 Well, this is awesome, Christian.

Speaker 2 So for my audience

Speaker 2 that's really interested in this podcast, where can they find out more about you? Yeah. Instagram.

Speaker 1 Yeah, so I

Speaker 1 joined Instagram a few years ago. So I

Speaker 1 wrote a book.

Speaker 2 Have you written a book?

Speaker 2 I have a book deal.

Speaker 1 I'm writing one right now. It's going to be out in May.
Okay.

Speaker 2 So I'm going to, I'm going to put the book. Really? Can they pre-order?

Speaker 1 Not yet, but I will certainly let you know when that

Speaker 1 available, but I appreciate that. Yeah.
So yeah, Kristen Holmes, 2126 on Instagram.

Speaker 1 I post on LinkedIn.

Speaker 1 And I don't have like this, a big old team or anything. So it's just me.

Speaker 2 That's okay.

Speaker 2 We love organic content. Yeah, yeah.
I just mine is very organic.

Speaker 1 Yeah, so I just, yeah, it's really low budget.

Speaker 2 It's low budget.

Speaker 1 Not produced at all.

Speaker 2 This is no budget. Yeah, no, no budget.

Speaker 1 But I'm, you know, I really try to get a lot of these insights out there. And, you know, obviously I'm very passionate about

Speaker 1 circadian health and sleep and recovery and training.

Speaker 2 Woke me up. I'm going to go deep down the rabbit hole.
I mean, you really, I knew that circadian health was important.

Speaker 2 I do that sunlight every morning, but I did not realize that the biggest variable, you you know, I don't have alcohol, I don't eat, you know, within a window.

Speaker 2 And those things are, you know, like, yeah, I mean,

Speaker 1 caffeine are going to be some

Speaker 2 EMF tenths. I did.
Next level with the sleep in there.

Speaker 1 I mean,

Speaker 1 the amount of modalities in this

Speaker 2 fortress of yours is just, it really is a lab.

Speaker 1 Yeah. Yeah, it's a lab.

Speaker 2 But

Speaker 2 I end every podcast the same way by asking all my guests the same question. There's no right or wrong answer to this question.
And that is, you know, what does it mean to you to be an ultimate human?

Speaker 1 I think just being able to wake up and live my values with joy and energy.

Speaker 2 Wow, live my values. That is a live my values.
That's a really good one. I might steal that one.
I like that. Well, thank you for coming, Chris.
And I'm definitely going to have you back. I mean,

Speaker 2 your journey is one that's kind of ongoing. So, you know, I'd love to see where you are six months from today, 10 months from today, because it really is exciting what big data can bring to us.

Speaker 2 And to have your background as a professional athlete, as a coach,

Speaker 2 you know, as you know, with a doctorate in psychiatry, now looking at the data in ways that are going to practically be applied to human beings, I can't wait to continue to follow your journey.

Speaker 1 I appreciate that. Thanks for having me.

Speaker 2 Thanks, Greg.

Speaker 1 Thanks for being here.

Speaker 2 Thanks for having me.

Speaker 1 Thanks, Gary.

Speaker 2 All right, guys. And that is just science.