← BETTER! Muscle, Metabolism, Meals, & Mindset in (Peri) Menopause with Dr. Stephanie Estima
BETTER! Muscle, Metabolism, Meals, & Mindset in (Peri) Menopause with Dr. Stephanie Estima
15 Minutes of This Rewires Your Brain & Metabolism — The Science of Lactate | Dr. Stephanie
00:42:20
Dr. Stephanie takes on lactate’s bad reputation and explains why it’s not just “exercise trash” but a powerful signal that can boost body composition, slow aging, and maximize brainpower. Watch the full episode at https://youtu.be/pfW_xKHNKPQ
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I don't want you to think about lactate as a failure of some sort. I think that when we have heard the story, like, oh, I'm burning, or I feel this stitch in my side, I think that we tend to equate that with failure. When you're jogging comfortably, let's say like a light trot, you're in second gear, okay? When you sprint like that, all out, ovaries to the wall, you are going for it. You, you slam into fourth or fifth gear instantly. So that rapid shift requires a different metabolic lane. I don't want you to become metabolically polite, okay? I want you to train power. And my hope is that in training your physical power, this will also alchemize into mental power as well. I don't know why, but we're having another resurgence of like, but what about cortisol spikes online, which, like, gives me all the angry ticks. But avoiding stress does not build resilience. If you have a really big, like, cognitively demanding task, like, maybe you have to study for something or you have a really big presentation or you have to memorize something, do sprint intervals earlier that day. All right, friends, welcome back to a another solo episode on Better. You guys are really liking these lately, so I thought I might do another little geeky magic carpet ride for you. And today we are going to talk about lactate. It is such a misunderstood signal and it can actually have some profound effects on your body composition on the way that you age, on your mitochondrial capacity. So we're going to talk about lactate not as the villain today, but as the upgrade signal.
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Betties treat it that way. So I want to dismantle this because I think that this is one of the most persistent myths in exercise physiology. For decades, lactate was framed as this, like throwaway metabolic debris, right? It was a waste product. It was the reason why you fatigued, it was the reason why you burned it, it was the reason why you slowed down. But here's the. I mean, and that's partially true, but it's not completely true. Okay? So lactate is a metabolic strategy that you can use to your advantage. Okay. I don't want you to think about lactate as a failure of some sort. I think that when we have heard the story, like, oh, I'm burning, I'm developing lactic acid, I feel this burn or I feel this stitch in my side. I think that we can almost tend to equate that with failure, right? That you've hit a wall or it's like the end of metabolism when really when we get that lactate signaling, it's actually just the beginning. So. And then maybe the other thing we're going to talk about today is how this is a signaling molecule for the brain. It connects the muscles to the brain. So let's talk a little bit about this. When you sprint, when you perform high intensity intervals, when we push you into that uncomfortable zone, what Juliet St and Kelly St. Might call the pain cave, you're not just producing burn, okay? You're generating a biochemical signal. And this is going to travel through your bloodstream, it's going to cross the blood brain barrier, it's going to bind to receptors, it's going to modify gene expression, influence mitochondrial density. And it's also has been shown there's some really interesting research that's coming out that talks about how it can improve cognitive function. So the entire premise, my entire goal with this episode is about re educating you on lactate and making a case for why you should be sprinting again, not just for your dream body, but sprinting does do that as well. But so that you develop this athleticism and resilience. And maybe we can even another solo episode, we can talk about what sprinting does to deceleration and elastic recoil and tendons and ligaments. But for the purposes of today, when we're sprinting, how that develops athleticism and resilience that you will. So as you get better with time, you are using sprinting as one of Those tools. So what we're going to cover today, how lactate is produced at the biochemical level. So this is a little bit deep roast for some of my Deep Roast Betties. Okay? But I promise you, I'll always bring it back to light roast in terms of how we can use it for everyday life. I also want to explain why lactate is not caused by a lack of oxygen. I think that there's a misnomer that once you run out of oxygen, that's when lactate is produced. And that's like partially true, but it's not the whole truth. And then I want to talk about the lactate shuffle concept. I want to talk about lactate as a role for fuel, as a role as a signaling molecule and its effect on the brain. And maybe most importantly, and this is kind of the central thesis, why sprinting and high intensity interval training produce this disproportionate adaptation, not just to lactate, but the fall on effect, like the knock on effect for what that does to the body and how you're gonna apply this knowledge practically. Okay. All right. So let's talk about the 80s and 90s, as I love to do sometimes on the show. I think that this is really where we started to see lactate becoming the scapegoat.
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Right?
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It's like you felt burning in your legs from a sprint or whatever it was, and someone would say, oh, that's lactic acid, or that's lactic acid buildup, right? And it's like, yeah, sort of. Right. Lactate does not really sit in your muscles. It doesn't stay there for a long time. It's not metabolic garbage. And even after a really high intensity session, lactate clears from your bloodstream within like, probably an hour after intense exercise. And I bring this up at the start of the show because when we label something as waste, it's like when we think of lactate as this, like, throwaway waste product, this poisonous material that, you know, air quote burns, then we avoid it because it's labeled as this sort of garbage product. And if we avoid intensity completely, I think that we are really avoiding one of the most powerful upgrade signals in human physiology. Because how you think about lactate is going to determine how you train, especially when you don't feel like it. And I will say, side note, I'm recording this after a brutal, brutal Norwegian 4x4. And I'm going to make the case as well today. Why, if you do have some very, very cognitively heavy tasks, why, maybe you should sprint before that and this is. This is my favorite thing is, is when you. You know, I always dread it. It's like as soon as I see that my Norwegian 4x4 has come up on my calendar, I'm like, oh, my God, can I just skip it? Do I really have the time for it? I just, you know, and then the whole like, mental monkey is like, you can skip it, you don't have to do it. And then once I actually get through it, I'm like, oh, my God, I'm. Am I actually superwoman? Is this how I feel? And then, you know, you're high on the endorphins. You're like, is this how happiness? Is this what happiness feels like? And this is what I want for you. Okay, all right, so let's talk about what lactate actually is, first of all. Okay, so when you consume carbohydrates, they are broken down into glucose. We all know this. So all the fruit, all the vegetable, all the homemade sourdough bread that you're making, maybe the oats that you're consuming, all of those get broken down into glucose, okay? And glucose is going to enter any cell via something, a transporter called the glute transporter. The very creative, these people, right? It's like, oh, glucose goes in there, okay, Glut, okay, so glue transporter, the glute transporter. So inside the cell, okay, so the glucose gets in via the glute transporter, and then glucose is going to undergo something called glycolysis. Okay, so this is back to your high school biology. You can I. This is a little dark roast here, but hang on, hang on with me. So glycolysis is a ten step enzymatic process. It occurs inside the cell. And the net result of glycolysis, okay, so the net result is you get two ATP, so two molecules of energy. And then you get two other things, you get two nadh. Okay? So just remember, nadh kind of sounds like nad. And you're right, it is. And then two molecules of pyruvate, okay? So two nad, two ATP and two molecules of pyruvate. That is the end result of going through glycolysis. But here is where the misunderstanding often happens. Okay? You are likely taught in high school bio that when oxygen is present, pyruvate goes into the mitochondria. When it's absent, when we don't have oxygen, pyruvate becomes lactate. Okay, I don't know if this is ringing any bells or you're like, oh, my God, what the heck is she talking about? But hang on. I promise, I promise I will get to why this is applicable to you. Right now. What I want to say about this is that's true, but not totally complete, okay? Because your body always produces lactate, even in the presence of oxygen. Okay? So in fully oxygenated muscle, lactate is continuously produced. It doesn't just get produced when you become anaerobic. Okay? And the reason for that is because glycolysis is going to run faster than your mitochondrial's ability to produce ATP during high intensity effort. So another way of saying this is when ATP demand, when energy demand, when that spikes, like in something like sprinting, glycolysis accelerates dramatically, right? Like that process of producing that two ATP, the two nadh, and the two molecules of pyruvate, that gets really, really, really quick, okay? Glycolysis, which is the energy production system, only can continue. So in high intensity and low, in all intensity efforts, glycolysis can only continue if NADH is converted or like recycled back to nad. You probably recognize the molecule nad. It is a subject of many. I mean, we'll say longevity bros, but. But NAD it we see NAD does decline with age. And the only way that glycolysis can continue is when that nadh, the H there's important, is recycled back into nad. And the way that that is done is an enzyme called lactate dehydrogenase. Dh Right? So it takes off the H, lactate dehydrogenase. This enzyme helps to convert pyruvate into lactate and then it also replenishes that nad. So it takes the NADH and cleaves off that H. So now we have that NAD plus molecule again. That regeneration keeps glycolysis running. So without lactate formation, glycolysis would stall. Okay, so I know that that was a little heavy. Let me say this another way. Lactate production is the way that metabolism can continue. Okay? It's not a failure because we didn't have oxygen. Right?
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You know that feeling after a brutal
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training week where your body is just
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tired and your brain won't shut off? I've been there. That is a dysregulated nervous system. And to be honest, it is absolutely sabotaging your recovery. Here's the thing that most women don't realize. Muscle is not built in the gym. It is built in recovery. And recovery is not just sleep and protein. It is your nervous system actually downshifting
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out of fight or flight.
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60, 70, 80 is built on all three pillars, not just two. Try muse@choosemuse.com forward/better and use code better at checkout. That's choosemuse.com better and use code better at checkout. Betty's sleep is not a recovery strategy. It is the recovery strategy. And if you are waking up at 3am running hot, or lying there with your brain doing its little highlight reel
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of everything that you forgot to do
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that day, this is your nervous system stuck in output mode because nothing in your evening told you that the day was over.
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So just to hammer this home during sprinting Glycolytic flux increases by up to like a hundredfold over resting levels. That is an enormous amount of like, metabolic acceleration, right? So I want you to think about lactate simply as the byproduct of speed. Lactate is the byproduct of speed, okay? So here's. Let's translate this into real life, okay? Think about it this way. Your body has different energy gears. When you're walking slowly, you're in like first gear. And if you ever drive a standard car, which is the only way to drive in my opinion, even though I currently drive an automatic car. But okay, if you, if you're walking slowly, you're in first gear, okay? When you're jogging comfortably, let's say like a light trot, you're in second gear. When you sprint like that, all out, ovaries to the wall, you are going for it. You slam into fourth or fifth gear instantly, right? So that rapid shift requires a different metabolic lane. And in order to get to that fifth gear, lactate is required. Like, you have to produce lactate in order to get to that fifth gear. It's like I said, it's what keeps that energy production moving. When we see that, that demand in, in energy spikes, right? It's like, you know, and it's like, thank God I was never involved in like designing the body because I would have never thought about this. But it's like baked in design of your body to be able to handle sudden increases in intensity, right? It's not a mistake. So what happens if you never sprint, right? Or even if you never lift heavy, or if you never move explosively? What ends up happening is you're never training that fifth gear. You'll become efficient, right? You become, you know, metabolically efficient, but you don't become metabolically powerful, you know? And if there's one thing that I want for you is to be powerful. And I want you to take up space, and I don't want you to be. I have this thought that's just delighting me, so I'll just share it. Like, I don't want you to become metabolically polite. Okay? Okay. I want you to be like, I want you to train power. And my hope is that in training your physical power, this will also alchemize into mental power as well. Okay? Okay. So here's why this becomes important for real women, you know, in real bodies. Metabolic health is not just endurance. Endurance is really done at that first or that second gear of intensity. Metabolic health is really at its core about flexibility, right? So you Want to be able to switch between fuels when you need it. You want to be able to produce energy quickly when you need it. You want to be able to clear glucose efficiently from the bloodstream, from the plasma when you need it. And the other thing you want to think about is like, can your body tolerate spikes in demand or spikes in stress? Right? Demand and stress kind of like, you know, two sides of the same coin, right? So I'll use those words interchangeably. If you're always avoiding high intensity work, you'll build that gear one and gear two, right? That aerobic efficiency, which is wonderful. We all should be doing that. But you may like, without knowing under train, that rapid glycolytic capacity, okay? And so that glycolytic capacity really matters when, let's say you've had a really high carbohydrate meal and you wanna be able to dispose of that glucose after that meal. It matters for your confidence in your athleticism, right? Like that, you know, you're going to hear me talk a lot about this concept of like body trust. You want to have athletic confidence or this idea of trust in your body, which is of course going to lead to like, down the line fall prevention, right? In your later decades, your ability to produce power. This is very, very important. You need to be, because you are a powerful mfer, right? Like you want to be able to produce power and you also want to be able to have nervous system resilience and intensity appropriately dosed. Teaches your body how to handle stress or how to handle demand is another way of saying that, right? Avoiding stress does not build resilience. And I don't know why, but we're having another resurgence of like, but what about cortisol spikes online, which, like, gives me all the angry ticks. But avoiding stress does not build resilience. It actually just makes you weaker with time. If you avoid lifting weights, like, your muscles don't get stronger, they get weaker. Your joints don't get stronger, they get weaker, right? So strategic stress is the key, right? So we want to be intentionally dosing that intensity, right? So I'm going to give you like a whole thing on, you know, how to apply this. But for right now, think about one, once a week, one controlled discomfort session. Okay? So Juliet would call this the pain cave, as I mentioned, but you must go into that pain cave and just get it done. So if you're a beginner, that might look like 10 seconds of something really, really hard, right? That could be. I actually really like the bike for, for a beginner, because you are minimizing impact and running, it's very hard to do well, et cetera, et cetera with technique. But something where you have a predicted line of drive, like a bike basically controls the way that you're, that you're projecting force. So 10 seconds, maximum 20, but 10 to start if you're a beginner, hard, like all out, ovaries to the wall, you are pushing it. And then like three to four minutes of a full recovery. And then maybe you do four rounds of that. Okay, Intermediate is going to be kind of the same thing, like 10 to 20 seconds all out, ovaries to the wall, right? But maybe instead of, you know, four rounds, you're doing like six to eight. And if you're advanced, instead of doing six to eight, now you're doing like eight to 10. Okay? So it's like 10 to 20 seconds all out, really, really hard. And then you're doing eight to ten times of that. Now recovery, as you know, is super important. You need to recover fully in between those intervals. And the way that I typically will monitor that is through heart rate. So you want to bring your heart rate down into like a zone 3, 2, right? If you're gearing up to like zone 4, 5 in those recovery periods, you wanna bring your heart rate like that 2 to 3 minute rest in between each interval, bringing your heart rate zone two, zone three. If you're not fully recovering in between the intervals, you're just training fatigue. Okay? You're not, you're not training, signaling you're not training lactate. Okay? So just something to keep in mind. Okay, so now we know where lactate comes from. That wasn't that painful, right? We can do biology on a podcast. So I wanna talk a little bit about the lactate shuttle. Because lactate does not just like accumulate like randomly, right? It moves. This is the lactate shuttle, okay? And this matters because this is going to change how you think about intensity. So instead of seeing sprinting as damage, you're going to maybe start to see it as more like integration. Right? Instead of seeing burn as like, oh, I'm accumulating this lactic acid and I'm breaking down my tissues. You're going to see it as lactate redistribution, right? And this is also my hope is gonna reframe your view on cardiovascular fitness, because your heart will become more efficient at using lactate as fuel. So when you have high intensity interval training, when it's dosed correctly, not every day, we'll get to that. But you know, when it's dosed correctly, it's going to improve your cardiac metabolic flexibility. And ladies, you've heard me say this, gosh, probably a dozen times now. Breast cancer is not what takes you out, okay? It's usually cardiovascular disease. It is the number one killer for women. Okay, so we wanna be thinking about our cardiometabolic capacity as we age. And sprinting is one of the ways to do it. Okay, let's get into the science of the lactate shuttle. So active fast twitch muscle fibers produce lactate. Those are your type 2B fibers. Okay,
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The lactate exits the cell. Okay, this is a little dark roast. Okay? So it exits the cell via something called the MCT4. For my nerds who want to know what that stands for. Monocarboxylate transporter. Not medium chain triglyceride. Okay, so MC before and so now lactate enters the circulation. Okay? Other tissues take up the lactate through MCT1 transporters. Who uses a lactate? I already told you one.
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The heart.
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Right? The heart is going to use it. Your slow twitch muscle fibers will use lactate. Your liver will use lactate, your brain will use lactate. Okay? And the heart in particular. I wore red lips for this discussion. In particular, the heart prefers lactate during exercise. It oxidizes lactate very Efficiently, very rapidly, the liver is going to convert lactate back into glucose, okay, via gluconeogenesis. We won't get into the cori cycle, but, you know, the liver will kind of recycle lactate, sort of in the reverse back to glucose, and then glucose can be released back into the circulation. So lactate, essentially, it's like, you know, when you put your green bins out at the, at the driveway, like once a week, it's recycled. Like maybe not the green bins. What is it? The blue bins becomes recyclable energy. So your lactate is being recycled. It's not waste. Right. It's, it's like. What would be the. It's like metabolic redistribution. It's like all the organs kind of getting together like at a, you know, Knights of Templar meeting or something, and they're all cooperating. Right. So when you're sprinting, you're not poisoning yourself, you're redistributing fuel to the places that it needs to get to. Let's translate this again. So your fast twitch fibers, they're like factories, they're producing fast energy, they're generating lactate, but instead of like dumping the lactate into a landfill or something, they send it into the bloodstream, right? Your heart's going to grab it and burn it, your liver's going to recycle it and it's going to make glucose again via gluconeogenesis, like we said. It's kind of like, it's like redistribute. It's almost like, I mean, I hesitate to say this, but I'm just going to say it anyway. It's almost like communism, but it actually works. You know, it's like not like the economic system that sends people into poverty, but in the body. It's like, it's like a communal sharing. Everything is redistributed, distributed. Right. So when you sprint, you're not accumulating waste, you're literally moving fuel from one tissue to another. So if you're somebody who already lifts weights, I would say if you're crunched for time, you can add intervals after your lifting session. Right. I wouldn't add them before personally, because lifting weights typically primes glycolysis. And then the short sprints that happen afterwards is going to amplify my lactate production. So if you're listening to the show, you probably do lift weights. So if you're short on time, add, you know, a couple of rounds of sprinting at the end of your training. Or if you have the luxury to be able to separate your weight training from your sprinting. You can do that too. Like, literally just whatever works. Okay? Okay. So I want to talk a little bit now about lactate as metabolic fuel. Because women are often just told, do more cardio, right? Spend more time, do more steps, burn more calories, right? It says eat less, move more stuff. But what I hope I am creating in this lactate masterclass, we'll say is that your adaptation does not not scale with time, it scales with signal and intensity, right? So a 15 minute interval session can create this, like, powerful mitochondrial signaling that's gonna matter for, you know, metabolic health, like your insulin sensitivity, your cognitive resilience, the way that you age. So what I mean by this is that you don't need to live in a gym, right? You don't need to be spending hours and hours and hours on the cardio machine. Like, if you have all that time and you have the desire, you know, knock yourself out. But if you don't, you need to think about how you can intelligently apply the stimulus to get the signal that you want. So during high intensity exercise, when we have rising lactate levels, this is going to, in terms of longevity, this is going to activate a couple of different signals that help with mitochondrial biogenesis, which is just like a super fancy word for making new mitochondria. If you don't know what mitochondria is, these are basically, we learned this again back to high school. Bio is like these are the battery packs of the cell. So these are the things that power the cell, that create ATP. So when lactate is rising, we correlate that, we can see that there is an activation of these, what I would call master regulators of mitochond biogenesis. AMP kinase, or ampk, you may have heard of that is one of the activators. And then PCG1 Alpha is the other. So both of those are involved in fat oxidation, so burning fat, mitochondrial replication, and of course, mitochondrial biogenesis. And then maybe more interestingly, at least for nerds like myself, is that lactate also? So it upregulates ampk, but it also appears to be a signaling molecule unto itself that is now going to influence gene expression. So it's kind of beyond the parameters of this podcast. But, you know, for my dark roasters who want to know lactate, there's some good evidence to show that lactate can upregulate something called angiogenic factors, which is just like vascular supply. They can modify something called histones, which is in centenarians and supercentenarians, we see a lot of histone expression. So lactate can modify histones and it can upregulate vascular supply as well. So when you generate lots of lactate, like a high lactate concentration, you're basically telling the body you're creating a signal that says, build more oxidative capacity. Right? And this is why these sort of shorter bouts of intense exercise can produce significant mitochondrial adaptation, even though the total exercise time is lower. Right? It's the intensity. It's all about the intensity, ladies. The intensity produces the signaling density. So when lactate rises, your cells receive this message. We need more capacity. We need more mitochondria. Build more engines, improve the efficiency of. Upgrade the system. That's essentially what's happening. So that short, intense interval will produce this disproportionate adaptation relative to the time invested. Okay. So you don't have to sweat for hours. Although if you want to, like, knock your heart out.
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Right?
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It's about a strong signal. It's about a strong signal. All right. I want to talk about the brain, because this is, in my opinion, maybe the most compelling piece of the whole thing. And that is to say that lactate crosses the blood brain barrier. Okay, Like. Okay, so when we see. When we see lactate produced, there's this blood brain barrier, which is basically the brain is obviously a neurologically immunologically protected site. So not many things get past it, but lactate does. Okay, so when lactate gets into the brain, it will activate a certain receptor in the brain. The name, okay, it's the HCAR one, for those of you that want to know, but, you know, it doesn't matter. Activation of this receptor, we see increased expression of bdnf. You've probably heard that little Alphabet soup acronym before. Brain derived neurotrophic factor. Okay. It will also drive angiogenesis in brain tissue. Again, better vascular supply to the brain, and it will also enhance synaptic plasticity. Now, bdnf, we know for the aging brain, right? You know how I know we all hate the word aging, but as we are getting older and better with time, BDNF is really important for learning. It's important for memory consolidation. Like, so the, you know, keeping the memories that we had. But also when we learn new things, to be able to consolidate those new learnings in the brain. It's important for mood regulation, it's important for neural protection. So high intensity exercise, when we elevate lactate, it seems to correlate with a higher post exercise bdnf. Okay. And so I don't know if you've ever noticed this, but if you've ever sprinted afterwards, you feel like, I always do. I always try to pair sprinting when I have a very mentally heavy task that day. Because sprint interval training can produce cognitive benefits, again, disproportionate to the duration that you spend. And so now when we get, when we think about sprinting, we're not necessarily thinking about sprinting, like, okay, I'm just like increasing my cardiovascular Fitness or my VO2 Max, although those things are very important. But we're also sending a brain growth signal as well. Right? Again, the acute lactate is like, it's almost like a metabolic alarm, right? It's like upgrade the energy systems, increase the vascular supply, strengthen the neural networks. This. Now when we think about sprinting again, it's cognitive training. You know the translation, I guess, or like said another way, if you will. When your legs burn, your brain is receiving this like update, right? This metabolic update. It's like the lactate is sending this message, like the energy demand has just spiked. We need more resilience, we need more circuitry, which I personally think is absolutely extraordinary. And this is really applicable to a woman in, in perimenopause. But I would say across her lifespan, if you're noticing that you are feeling like you're a bit more foggy, maybe experiencing a little bit more brain fog, you're feeling overwhelmed from the demands of your life, you're feeling stressed, maybe you even feel like, I hear this a lot in women in their 40s and 50s, a little bit more cognitively dull. Moderate cardio is great and helpful, but when we spike the lactate, that is gonna add this extra layer of like neurological stimulation where you are now deliberately driving neurological signaling and maybe improved, like cognitive hygiene, right? So if you're someone who's experiencing brain fog, try integrating, even at a beginner level, it's like 10 seconds, do that. Like, you know, do a 10 second sprint, recover for three minutes, and then do that four times and watch over the next several weeks if you don't see that brain fog improving. Right. The other thing, I kind of hinted at it before, if you have a really big, like cognitively demanding task, like maybe you have to study for something, or you have a really big presentation, or you have to memorize something, do sprint intervals earlier that day and then, you know, recover, like wait 45 minutes, 60 minutes. Now the lactate is like now clearing from the body and then do the deep work, like Pair the physiological stimulus, the lactate, with the cognitive demand. I did that this morning. So I did my Norwegian four by fours and now I'm recording a little soliloquy, if you will, on lactate. It works really, really well. When I was writing my book, the first, you know, the first draft of the manuscript, that's how when it was writing day, I was doing my Norwegian 4x Fours because it made a phenomenal difference in my ability to think and write and be creative and be punny, you know, like using puns, but they're funny, you know, like just trying to, you know, integrate all my quirks and jokes into the book. That would be my best recommendation for you. When you have something really cognitively demanding, try to do the sprints earlier that day if you're able to. And again, if you have lifting on the menu that day, just do a couple of sprints at the end of your lifting session. Okay? So let's talk a little bit about dosing and recovery because I know y' all are. I know who I'm talking to. I'm talking to my type A's, my type A Betty's. More is not always more. Okay? So intensity is really powerful, but if you misuse it, it can be completely destabilizing. Right? So I want you to monitor if you are sleeping five or six hours, it's not enough. If you are chronically stressed, if you are under eating your protein, if you are not recovering like you're paid to, adding more high intensity interval training is not going to provide the signal that you're hoping for. It's just going to contribute to overload. Okay? When you are driving such an intense signal, you need to think about restoration. And this is why this cannot be done every day. I honestly, to start once a week is plenty. And there are many weeks when that is all that I do. It's just once a week because it is enough. Two times a week, you're kind of nearing your maximum. I wouldn't do it any more than that, if I'm being totally honest with you. So practical couple practical rules for you. Never do high intensity interval training if you've had less than six hours of sleep. Never do more than three back to back high intensity days in a row. You need to recover from them. Okay? And I would also say keep the total interval sessions under like the time that you're doing, the intervals under 25 minutes, right? Per session. Like that doesn't include the recovery base in between. But I mean like the intensity, the intense part so, for example, when I do Norwegians, I do four minutes on and then three minutes off, and I do that four times. So the total interval session is four minutes times four. So 16 minutes in total. And I do that usually once a week. Okay. If you also notice that you're losing control of your heart rate. So, like, your heart rate is just like going bananas. You can also reduce the frequency or the intensity as well. I did. It's a couple years old, but it's still such a great podcast episode. Phil Maffetone, we were talking about how to use your heart rate max. He calls it his, you know, fat max for optimizing fat burning. But it was such a great episode. I'll link to it in the show notes if you want. It's an oldie but a goodie. Using heart rate to tell you kind of when you're finished. Okay. And then the other thing, of course, always to recognize your motivation. Right. So motivation is a flaky friend. She's not always there. But if you are consistent consistently noticing like week over week over week that you just don't want to do it, you need to have. You need to either reduce the volume or increase your recovery, which is kind of two sides of it of the same coin. Okay. Okay. So let's translate this into some programming for you. Okay. So I know that you want all the brain resilience. I know that you want all the cognitive sharpness and the metabolic flexibility and the lactate signaling and building your dream body, and the insulin sensitivity and all the things, the mitochondrial density. We also talked about that today as well. In order to achieve all of those things, you need some periodic high intensity efforts. Okay. So a couple different ways that you can start. Okay. Safe and effective. So I really love, I've already said this before, but bike, I really love a bike interval. Once a week, you can start off at 10 to 20 seconds, four rounds, and that's it. If you're someone who's run track in the past, and if you are live in a place that you know you can run outside, you can certainly do that. You know, just translating that into track sprints as well. Uh, the rower is also an interesting one to do high intensity interval training on as well. Like again, 10 to 20 seconds, really, really hard, somewhere between four and 10 rounds, depending on your, your proficiency and your fitness skills. And then if you're psycho, I'll say you could do hill sprints, which are just orders of magnitude worse than track sprints, because instead of just running on a flat surface you are now doing it uphill. So again, same kind of thing, like 10 seconds. I would probably do like maximum like 8 hill sprints and then like kind of walk back down the the hill for recovery. And then the other option, of course, I've mentioned if you are someone who strength trains, at the end of your strength training session, you can, you can throw in like four to six rounds of, of sprinting. Now, if you can talk, you are not generating a significant amount of lactate. This is like, I'll say it this way. When I am doing like zone one, zone two, I do my duolingo on my app. You know, like, I'm doing my language lessons, I'm, you know, texting people, I'm sending voice notes. I'm, you know, on Instagram scrolling. That's like gear one and gear two. You should not like, it should be 100% of your focus for that 10 seconds or 20 seconds. You should not be able to do anything else. You should not even be able to hold a phone during that sprint. Okay? It needs to be uncomfortable. So starting once a week, if you're deconditioned or you're a beginner, and then your recovery days, I would actually build in if you, I would start off with once a week. I've said this before, but if you want to do more than once, I would build in two days of recovery days as padding around like on either side of the high intensity interval training. So I would do like, let's say, let's say Monday, for example, you do the sprinting. I would make sure that Tuesday and Wednesday, zone one and two aerobic work. And then maybe even the Saturday, Sunday is the aerobic work as well. And then if you wanted, you can do it again on Thursday, right? And so then again, you've had the Tuesday, Wednesday as your zone 1 2. And then you can have Friday, Saturday as your, as your buffer. Okay, so zone 12 aerobic work, that's like walking cardio machines for sure. I would definitely be putting in mobility, especially if you are doing track or hill sprints. And then of course prioritizing your sleep. And that's like the big key. If you stop, if your sleep is starting to get disrupted from too much intensity, then that means that you are overdoing it. Okay. All right, my friends, so I hope I have succeeded at convincing you that lactate is not waste, right? It's that fuel redistribution, right? It's brain signaling, it's vascular remodeling. It's like, it's like if you've ever renovated a house and you're like, oh my God, these walls, this arc, you know, this electrical wiring, it's terrible. Lactate is going to remodel your electrical wiring, your nervous system, but also angiogenic. It's going to also redo all the plumbing, you know, all the cardiovascular work as well. And so I hope that the next time your legs burn during a sprint, you will with delight know that this lactate that's being produced is upgrading your signaling that it is communication and that you are literally remodeling yourself to be a better, more resilient version of you. Not accessibly not, you know, but strategically.
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Right?
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So there you have it. I would love to know what you thought of this episode, so let me know in the comments if you want more solo episodes. What topic? Let us know whether you are commenting on Spotify or Apple, wherever it is that you listen to the show. We are so excited to hear from you, our community in the Bettyverse. So until then, I bid you adieu and thank you so much for listening.
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I hope you enjoyed today's episode. And now I must give you the obligatory legal and medical disclaimer. This podcast, Better with Dr. Stephanie, is for general information only. The advice and recommendations we discuss do not replace medical, chiropractic, or any other primary healthcare provider's advice, treatment or care in the consumption of this podcast. There is no doctor patient relationship and the use and implementation of the information discussed are at the sole discretion of the listener. Please take this information to your primary healthcare provider to make the best choice for you. Remember, I am a doctor, but I am not your doctor, and these episodes are meant for educational purposes only.