EPISODE #978 How to Hack Your Cardio Workout - Ulrich Dempfle

You're listening to the Human Upgrade with Dave Asprey. Today, as I promised, I'm going to tell you what you're going to learn before you learn it. So you decide that this episode is worth your time. We're going to talk about new research that shows you the most effective cardio workouts. And I'm going to tell you to do it in 15 minutes a week and get pretty interesting results. Better than you'd get from, say, two hours a week. And we're going to talk about one of the newest innovations here. It's called the Carol Bike 2.0, which has a bunch of AI derived features that allow you to do this. And they are sponsoring this podcast episode. And I appreciate that because Carol's doing research that kind of goes against the grain. All of the big fitness industry, all of the exercise industry is like, do it more, do it more, do it more. And that's actually not how it's supposed to be. Even Netflix. Watch it more. Watch it more. Watch it more. Netflix has told us that their biggest competitor is sleep. Literally, they believe sleep, your sleep, is a competitor to them. And when we flip the script and say, what if you could watch one minute of Netflix and get all of the enjoyment and all of the knowledge you would have gotten from six hours of Netflix, isn't that in your best interests? So what biohacking is about is doing what works best for you. And I think with the Carol bike, you're going to realize, wow, I'm going to think differently and I'm going to be a little bit selfish and say, well, can I do less of that? Because I actually didn't want to spend all of my life in the gym, even if the gym company is wanting you to spend all of your life there. So that's how to think. Carol's thinking about your time as being the most valuable thing. Oh, and doing a better job of fitness than the other guys who are wasting your time. Anyway, our guest is returning today to talk about brand new research that just came out about cardiovascular fitness. His name is Ulrich Demflo. Ulrich, you co founded Carol and you've talked about it on the show before, but not every listener heard the last thing. And you talked about something called rehit. Can you walk me through what REHIT is? Just so we're all grounded?

Yeah, sure, sure. So rehat is short for reduced exertion, High Intensity Interval training. And it was basically developed by scientists looking for the shortest, most effective and most accessible way to exercise. And proper scientific research proved that Reheat is the fastest way to get fit. And basically it gives us workouts that fit into into any schedule. In rehit, you just do a small number of very short but very high intensity sprints. So all you need to do is two 20 second sprints as part of a five minute workout. And you do that three times a week, 15 minutes a week, and have all your cardio. And it's scientifically proven to be the most effective cardio workout.

Gee, five minutes, three times a week. I'm pretty sure that even the laziest person listening to this podcast could do that. Oh, by the way, that's me. Just to be really clear, laziness is a moral virtue. And whatever church or whatever factory boss tried to make that in our society to tell you that laziness was something to be ashamed of, they were wrong. Because the bottom line here is mother Nature wants us to be lazy. It is built into our bones to not do things that waste food. And every time you do something, that's why we have a resistance to exercising. And what you're doing with Carol that I really like is you're saying, well, let's just honor the fact that you don't really want to exercise that much. You just wanted the results. We're willing to exercise, get the results, but we don't want to. So I can do five minutes. I really can. And I don't have to sweat during the five minutes, do I?

That's right. And it's also really important to understand that even if you do work out for an hour or longer, you don't get fitter, you don't get stronger while you're working out, you get fitter and stronger in the recovery periods between the workout. So what you want to achieve is you just have to give the body a stimulus to basically trigger that adaptation. And rehit can produce the most potent, the most powerful stimulus with just two 20 second sprints and you're done in five minutes. And it's scientifically proven to be the most effective cardio workout.

Well, there you go. And I believe so much in this that we've got a special custom version of Carol in all of the upgrade labs. It's different than what you, you get if you're doing, if you're doing Carol at home. And it's integrated with our whole data system, which I'm really grateful for our partnership on that, but I want everyone listening to the show. Seriously, all your life, you have believed the simple thing that our monkey brains believe. Our brains are also lazy. So we like to just make basic rules. And one of the things that we believe, and certainly I've believed, is that more is better. If something is good, more better. And it's so easy to believe that it takes almost no thinking. And thinking also takes electricity. So we don't want to think and we don't want to exercise because our lazy biology, our cells are like, don't waste the electricity. Could we just take a shortcut? Well, the more better shortcut led me to be a vegan. And when I started getting sick from it, I became even more vegan, more devout, because I thought something worked. I thought it worked better. Then you get the world of keto. I thought, well, okay, if keto is good, I'm going to do three months of only meat. And ruined my sleep quality and gave myself some autoimmune issues because I gave myself leaky gut because I went a little too long before I cycled.

Right.

So I've learned this value of temperance and I've also learned the value of laziness, which says more is not always better. And it turns out with cardio literally sitting there and writing really hard like I used to as a road biker, it doesn't get you the results, it just gives you endorphins though, right?

Exactly, exactly. And that's, that's how we've arrived at it and how our scientific partners arrived at it. We, we thought it about it really from a perspective, what stops people doing exercise? And you know, most people don't exercise enough. In fact, 95% of Americans don't exercise enough. And if you ask them what stops them from doing it, it's not lack of endorphins, it's lack of time. So the thought process was, well, if that's the key barrier, how can we overcome that? There we've really gone backwards and tried to undo this more as better and just looked how little is enough. And it's really, it's been successively, you know, like titrated down. What's the minimum amount that you can get away with to get the results? And for the vast majority of people, it is just two 20 second sprints packaged in a five minute workout. And then if you do more sprints or longer sprints, there's just not additional benefit. It's literally like flipping a light switch. The light is on the first time. You don't have to press long and hard. It's just, you need that stimulus. And then during the recovery, you get fitter and stronger. You don't have to keep Pressing the button. That's just doesn't help. Almost not always better.

It doesn't help. But, and I am guilty of this, and I'm hearing it with you as well, I say this all the time. Oh, only 8% of people exercise the amount the U.S. government recommends. And we all say, oh, but people don't exercise enough. But it turns out the reality is that people are exercising too much. They're just doing a crappy job of it.

Yeah. Sadly, the recommendations recommend a certain amount and are very old school in a way. And there's the, the research is just way further than than the recommendations and the guidelines.

So what we're seeing is exactly one of the big dreams for me that the reason quantified Self was so interesting as a movement. This is going back, geez, 12 years now when a bunch of nerds got together and said, let's start measuring the signals coming off of our body. And the original vision and Quantified Self was sort of like, well, let's just get the data, it's so interesting. And then the biohacking movement, well, so let's do something with the data to create a change in the body. And last year when I talked to you, you had taken a bunch of data from humans and said, all right, we've got the workout down to 8 minutes and 40 seconds and before that it was 12 and now it's down to 5 minutes. How low are we going to get it?

So I think the 2:20 seconds are pretty much the least you can do that we know of now. Maybe it gets lower, but I don't actually think reducing it to 2 times 15 or so would get more benefits. Effectiveness is one side of it. Like what, what are the health and fitness benefits you get out of doing it? The, the other angle is also how you feel and how the workout makes you feel and how likely you are to do it. So I should kind of almost like as a little, you know, disclaimer, the two 20 second sprints are not easy. You go to maximum intensity and it's quite hard. Yeah. And once you've tried it once, you will understand why it's effective and why it works because you push your body to your limits. And so two 20 second sprints for some, like most of our users have fabulous adherence rates. So for our new customers, we track their adherence, we're really happy with them. But for some, two 20 second sprints might be too long. So we've also included two 15 second sprints, which is, you know, you do get slightly less Benefit, but it might make it just more achievable and more doable for some. And so that's a exciting area of research, is kind of the combination of sprint duration, sprint intensity and recovery to really get the optimal emotional response as well. So there's for example, research out on a new workout that has 106 second sprints. So overall a little bit longer 60 seconds instead of 40 seconds hard work. But those shorter sprints for some are just that little bit more doable that they can actually stick to it and adhere to it. And that's, that's really, that's adherence is king. Like the, the, you know, the best workout is nothing if you don't do it.

Um, I, I am really impressed with where research is going. And the Carol bike is, it's kind of a platform where over time you'll be able to get tighter and tighter on this. And certainly that's what we're doing with Upgrade Labs and why I selected Carol as our partner there because we can customize working with you to continue to get more benefits. I don't know where the bottom line is. It may be that someone's going to discover based on this huge data set that we're gathering about our species. Well, it could be that you need 133 second workouts over the course of 94 seconds, I have no idea. But we're going to get down there and what I fervently believe is that it's not going to be the same for everyone. So I'm a 6, 4 wall of muscle, at least that's what I like to tell myself. And I probably have a different number than someone else who might weigh half what I weigh. Also, maybe I'm tired because I just got back from Peru and so my number is different today than tomorrow. So my dream and the one I'm working on is to be able to integrate all this. So we know who are you? What do you need today? What's the ideal stimulus? And so it's that combination of all the different biohacks that you can do. And I think this is the most effective and efficient cardiovascular, cardiovascular thing out there right now, which is. I'm super excited about it. It's something that, well, you can't put in your suitcase yet, but it's something you can have at home or something you can do as part of an Upgrade Labs experience where you're doing multiple things at the same time. So I'm stoked on it. And you're saying over time we might get to less than five Minutes.

Yeah. So that's one thing. Yeah. And if time is, I mean, many people, I hope, value their time and will appreciate that because you can save just a ton of time with it. And then the other thing is kind of making it as nice and as pleasant as possible so that you are able to do it. So the personalization and optimization that we've driven so far was just minimum time for maximum benefit. But we have data, you know, from hundreds of thousands of workouts. And if you, if you think like a scientific study, they would have 20, 30 subjects, they would do it for over six to eight weeks. So they get hundreds of rides. We have like a huge multiple of that. That allows us to, you know, push the envelope further and make the bike better and better. And because the bikes are all connected, whenever there is new insight and new research out, we can build that into our algorithms, we can build that into our platform. And your carol bike will only get better over time.

That is ridiculously cool. I'm looking at the comments from the Upgrade Collective, my mentorship group, and wow, a lot of them already have a carol bike and they're talking about all the things that they do with it and the benefits are real. A couple of people are asking though, do you need to warm up before you do this?

You don't actually. No, I don't. The warm up is something. So in that five minutes, we've allowed for a 20 second warm up, but that's, you know, just getting into position. The warmup really doesn't do much. It's, it's the two 20 second sprints that create the stimulus. And then what is actually something that we don't want to skimp on and probably wouldn't reduce is the cooldown. So there's 3 minutes cooldown at the end just to kind of normalize afterwards. So you go all out and then you allow yourself three minutes to just cool down again, blood pressure comes down and so on, that we wouldn't shorten. But it's, it's really the two 20 second sprints, that's, that's what creates the stimulus and that's what makes you then ultimately fitter.

What would happen if I did, say, 20 of these 15 second workouts? Wouldn't I get more benefit? Or 20 second workouts, whatever. If I did a lot more, am I. Or even three instead of two?

So that's, that's been quite comprehensively shown that. No, you wouldn't. It's, it's really. Doing more is optional if you enjoy it, if you get the endorphins you can, but you don't get additional benefit from it. Wow. So that's not how this particular exercise works. Our recommendation is to do it three times a week. And that's been shown to, to work even two times per week has been shown to work for the fitness benefits. Especially if you'd like to do it more. You can, but you really don't have to. There's no good reason other than I really enjoy doing it. Yeah, no. So the thing about exercise that's I think quite important to understand, it's not like a one off that you do and then you fit exercise. Like I, I think of it very much like diet or nutrition. Like you can build and can make a massive amount of positive change in a surprisingly short amount of time. So in six to eight weeks you can feel completely different. But if you don't stick to it, you will lose it again as fast as you gained it in about six weeks. Yeah, that's an inconvenient truth about exercise. And that tells you that you need a plan. You need to have something that you can stick to that fits into your life. That's not just because it's got a great soundtrack and maybe an inspiring person yelling at you. It needs to fit into your everyday life. And we found, well, with five minutes three times a week, scientifically proven, that is something that people can adhere to and it's basically a long term plan and something that you can stick to.

And Ulrich, I have to admit, going back two, three years when I first started talking with you guys, I think this is bullshit. It's the dream, but I don't think it's real. And then I interviewed your research. I think it was Lance from the University of Colorado and was like, oh wow. Like no, this is serious third party academic research. And having used it, it absolutely, absolutely works. And the problem is, and some of the Upgrade collective are talking about so like, but I like the opiate, the endorphins from exercise. Like I want to get high. It calms my mind. And for those people, I mean should they get on their carol and just keep doing it or.

I think they, they, they can and so Carol will, you know, it's, it's a fallback option. So some people might not always have time. Like they, they might enjoy the long workouts, but you know, you, you go through different phases. You, you might have a busy period and then this is like your insurance policy.

Now one of the things that I've used over the years to determine whether I've over trained or just overstressed is heart rate variability when you wake up. If your heart rate variability is low, hey, maybe you need to take it easier. And one thing I know that Carol does is you're looking at heart rate during the exercise. Is that what you're using with the algorithm to determine how intense the resistance is?

So this is a coming feature. So with our Bike 2.0, we provide a wearable heart rate monitor and actually everybody on our current bike who uses one of our heart rate monitors, the wearable heart rate monitors, we do measure HRV during the warm up period and we collect the data and analyze that and this is a feature that will come in the next two, three months to basically use heart rate variability to further kind of micro personalize and optimize the workout to you. So yes, if you're not in perfect shape or it's not the time of the month for you to perform at your highest level, that we make it somewhat easier for you and take it into account. So yeah, that's something that's coming, that's in the analysis and R and D stage, but we're very close to that. And that's over the next two to three months will be launched.

What's the gold standard you're using to measure effectiveness? Is it still VO2 max?

So on the Carol bike, we've got our own, we call it just a fitness score and that tracks and mirrors VO2max. And yes, for fitness benefit, VO2max is generally, it's probably just one of the most important health markers and predictors of kind of healthy life expectancy and longevity and health. That's around. So VO2 max is, is the most important metric really.

So using the current Carol 2.0 bike algorithms, people are still getting a 12% improvement in VO2 max in about eight weeks, right?

That's right, yes. So in terms of effectiveness, there's no difference between 1.0 and 2.0. It's about flexibility and choice. And yes, you get, and that's scientifically proven, 12% increase in VO2 max in just eight weeks. And that if you, if you think about what that means to you, it's really a very, very substantial, very noticeable improvement. It's not subtle at all. If you like, we all lose about, as we age, about 10% VO2 max per decade. So in essence, in eight weeks you can dial back your fitness levels by around 10 years and you feel that. So it's very noticeable. You'll see the difference, you'll feel the difference?

Couldn't you just sprint for 20 seconds and then just rest and then sprint for 20 seconds? Does it do the same thing?

So, I mean, we do get asked the question, can't you do it in other ways? And first thing is take it on trust. If it was possible, we wouldn't have spent the last 10 years developing an automated bike that makes rehit kind of as safe and as effective as possible. If you wanted to do it without a carol bike, I mean, first a few don'ts. I think it's absolutely impossible to do it on a treadmill, a stepper, an elliptical, all of those things. I think it would be really just unsafe if you wanted to try it on a normal exercise bike. Well, that's what we've tried 10 years ago and we just couldn't get it to work. And then when we asked the scientists why it didn't work, they first thing they said was, well, you need a special bike for it. Bodyweight exercises, any of those. I think the load is just not fast, it's not high enough, and you don't get that increase in load fast enough. Sprinting, frankly, I think of all the alternatives that are out there is probably the next best thing. So if you were to try to do it really on a budget, yes, by all means, go out on a sprint track, gentle jog, and then do two all out 20 second sprints. You might get some funny looks. And you don't see people in a park very often kind of going really all out. And there's obviously a trip hazard and you need to be careful not to fall. I think especially for people who might have some mobility issues, who are a bit older and so on. Not to underestimate, but that would be the next best thing in my judgment. You wouldn't have any of the data, you wouldn't have the tracking, but by all means, yeah, if you're really on a budget, try that, see what it does to you.

And this is one of the chapters in my new book, Smarter, Not Harder. It is okay if you're not gonna get a carol bike. What we know now is the most efficient algorithm is to do that. But one of our Upgrade Collective members says, yeah, my husband tried that. It's just too hard on the joints. Guys, this is the kind of running you would do if literally there was a bear chasing you. The all out I am going to die. And what the body will do in an uncontrolled situation like that, even if you're just running in the park, is, I mean, it's sure you want to pull a ligament, it doesn't matter. It's got to be really high intensity and you're dealing with your body weight and relatively high impact. When you do that, you're sprinting like you're going to die. And I kind of like the idea of having that intensity level on an exercise bike, which is why I would prefer Carol for that.

And an exercise bike is in terms of safety and how should I say? Like, like it's. It's obviously very high intensity, but then low impact exercises, it's much more gentle on joints than the vast majority of other exercises that you could do. And if you look at who I mean, we've got a huge spread of users, but many of our users are in the 40 to 60 range. And in fact we've got many users who are above that up to 80. In fact, we have a few that are over 80 who can still do high intensity exercise safely on Carol because we have all these because it's a bike and it's kind of hyper personalized to you, we've got a number of safety features and certainly I would think safer than any alternative.

I think it's the best way to do it, which is why I'm a fan and a supporter and I'm integrating all of the Upgrade Labs tech with your data set so that we can do all these custom things. And that's a really big investment of just time and energy for me. So all in on it. One thing that the Upgrade Collective members are asking, and you may not have any information on this, but I'm curious as well. I've had several episodes and I'm also in the new book writing about blood flow restriction training. Have you had people try and use blood flow restriction training like the B strong bands while they're doing the Curl bike? Do you recommend it? Is it a good idea? Is it a bad idea?

So I know of some of our users who do do that. I've tried it myself. Don't do it regularly, just out of curiosity, but yes, absolutely. You can combine it with blood flow restriction bands if you so wish. I don't think it's a standard. Don't think is something that many people do, but I've heard of it. Yes. And I know of a few users who do that.

You know, I'm pretty darn sure that it can replace a $45,000 system that takes a lot longer to use just by restricting some blood flow to the limbs, which is really convenient. And a lot of people listening who are from the traditional exercise science, exercise physiology world. They're already standing there frothing at the mouth, swearing, because this isn't what they learned in college. Right. And this isn't what supports people coming in for an hour, three times a week to do workout sessions. This is just cardiovascular training. This is not functional movement, this is not muscle training. This is to make the cardiovascular system work. Right. So you have the power to go do the other kinds of exercise. So normally blood flow restriction training is in place so that you build muscle more quickly, so you might restrict the blood flow on your arm. And then you're going to do your curls and you're going to get more of a pump and there's a lactic acid change and all these other things that is not the function of Carol. But will it probably help your legs? Probably will. Right?

Yeah. And that's actually, we only got the results very recently. So this is actually a piece of research that Professor Lance Dalek in Colorado did. He looked at the strength benefits of rehit and rehit specifically on Carolina and found that in six weeks and only six weeks, you actually get meaningful increases in muscular strength. So like your one rep max in a squat and found that participants, like subjects in a scientific study there increased their leg strength by 14% in six weeks. So Rehat is done at, you know, a muscular load that's also meaningful for strength training.

Okay.

And I've heard that. So this is. I know that many of our users who are in contact with us, they understand that cardio is one thing you do for exercise and that strength training is also important. But they've told us that they notice and we also see it in that data, of course, that doing rehit on a Carol bike improves your lower limb strength. They can focus on upper body and frankly skip leg day, which is the hardest part for many people who like resistance training. So there is a meaningful benefit on strength for your lower body, not for your upper body, of course.

Talk to me about burning calories on cardio. What do you think about that?

We have a range of different protocols in our very short the signature rehab protocol, because it's so short, you actually only burn a relatively small amount of calories while you're on the bike. But because you go to such high intensity levels, you burn more like you have a large amount of afterburn or excess post exercise oxygen consumption. And in fact, you burn two thirds of the calories from a caro ride after you've gotten off the bike. So there's in the 90 to 180 minutes after the ride. So that's. And that even though it's so short, you get a meaningful amount of calorie consumption from doing the workout. So if I do our signature workout, that leads to a calorie consumption of something like 200, 230 calories, which is not insignificant. That's like 10% of my baseline needs. And then if you, if your primary goal is weight loss, we do also have others. We have a fat burn series that's not quite at. So there you do more sprints at slightly below maximum intensity, so they're shorter and more of them. It takes about 15 minutes or up to 30 minutes if you wish. And there you burn just loads and loads of calories on the bike and also afterwards. And even more important than calories because calories is always, you know, it also depends like on nutrition obviously, vastly, vastly important. But it's been proven to help with actual fat loss. So in the, there was a great study on obese women where that particular fat burn. Right. Has been proven to lead to nine times more fat loss. And that's kind of the end point for most people that they're after than traditional moderate intensity exercise.

So one other question, it's kind of different for men and women and I've interviewed a bunch of women, professional athletes. I've written chapters in my fasting book on women. There's, there's just different biohacks here. What have you figured out with all the data you have at Carol about women and doing rehab training?

So this is not just our data, but we, this is a hot topic for research. And so for example, Professor Gibala at McMasters University, he's, he's doing a big year long study and he's using Carol bikes for that study to investigate the differences in the male and female response to rehit. Now that study is ongoing. I don't have all the results. We do know that there are differences, but we're still working and we're partnering also with the leading researchers to understand what are the differences, what drives the differences and then what recommendations can we give. What our users tell us is that for women certainly menstrual cycle plays a role and that they perform better at certain stages of their cycle. And that's a well known fact. So professional athletes, pro athletes, time, or many do at least I don't know whether every single one does but time their monthly cycle. So they're at the right stage, at the mid follicular stage for competition. For competition. So that they're really at Their best. We don't plan to track our female users menstrual cycle on the bike, but what we do know is that HRV is also linked and driven by the menstrual cycle. With tracking HRV during the warm up with a wearable heart rate monitor and then adjusting the ride accordingly and making it easier or harder and also just taking it into account whether you have a good day or a bad day in our longer term optimization we basically try to take that into account in the easiest possible way and so just make it easier to perform for our female users.

So what you're saying is when a woman is menstruating it will change her heart rate variability and that's enough for you to change the intensity of the bike without having to know exactly when the menstrual cycle is.

That's it. That's it. And it will also help you when you're coming back when you've been on a long haul flight and you, you didn't sleep very well. So it's the, the benefit is there for, for men and women but, but for women it's, it's kind of, you have this monthly cycle that's just there and that has a big impact.

Well, keep in mind too, 85% of women have used hormonal birth control that breaks their cycle throughout at some point in their life. And a huge number of women are on that which can affect this quite a bit. So I would say that given the preponderance of evidence in my fertility book, my anti aging books and the dozen experts who said that's not a healthy practice, even if you're doing that, if there are changes in your heart rate variability, they'll be reflected. So the bottom line is you don't have to have any kind of invasive data gathering whatsoever. You're just hey, what's the state of the system today? And then let's change the intensity up and down which is, which is really smart. Okay, what about men? What do you see with testosterone levels and things like that?

Every exercise is actually helpful for testosterone levels, but that rehit and hit is more helpful and leads to higher levels of testosterone, growth hormone, lower levels of cortisol. So therefore it's just superior, it's a superior type of exercise versus long cardio.

Lung cardia reduces growth hormone and testosterone. That might not be the ideal choice for most people. Just saying, I mean you say something.

There with biohacking or kind of hacks. I do a bunch of stuff where, and take a bunch of stuff where I'M not really sure whether it works, but I'm kind of convinced that serious people or trustworthy people recommend that it's good and I go with it. So I'm quite happy to accept. And as long as the, the effort I have to put in is low enough, I'm quite happy to do it. Carol, basically, the response you get and how noticeable and how clear the benefit is and also how quickly you can feel it, I think is very, very convincing and something that's very easy then to, to stick to, because, yes, you do something, you have to do it three times a week, five minutes, 15 minutes in total, but you get not only a scientifically proven benefit, but something that you really feel very noticeable yourself that makes you perform so much better in all sorts of ways in your everyday life because you are just so much fitter.

Well, I think that you're putting your money where your mouth is, you could say, because you give everyone 100 day home trial of the Carol 200 bike, so you'll send it to them and if they don't like it for any reason, they just send it back. And that's plenty of time, given that it only takes eight weeks to see this massive improvement. So if it turns into a clothes hanger for you, it should happen in the first eight weeks and then you send it back. Are you willing to say what your return rate is?

It's very low, otherwise we couldn't afford it because.

Fair point, you're still in business.

That's like the 100 day home trial is really risk free. So you don't have to send it back. We collect it. And unfortunately, with fuel rates at what they are, kind of shipping bikes back and forth is very expensive. That's just the truth of the matter. So, no, they're very low and the vast majority keep them. If everybody gave them back, I wouldn't be sitting here. I hear you.

So people are satisfied it does work. And I absolutely know that because I've worked on it myself. So, guys, go to carolbike.com you can use Code Human Upgrade and they'll give you two years of membership worth about 360 bucks. And if it doesn't work, you can call Ulrich and disappoint him with high fuel charges. But I'm just telling you, you can do five minutes three times a week. It's just the smallest possible thing you could do. And after that you can check off your box that says, I'm a good person because I took care of my cardio. You didn't have to take the stairs at work. You didn't have to do all the crap that is on your to do list for exercise, for cardio. It. That stuff wasn't real. We just didn't know how to do it. So I'm. I'm a huge fan of this and carolbike.com code human upgrade and enjoy. Ulrich, thanks for coming back on the show. Thanks for getting us from 12 minutes down to five minutes.

Thank you.

You're listening to the Human Upgrade with Dave Asprey.