Exercise Expert: How Women Can Burn Fat, Build Muscle And Age Strong | Dr Kristi

You burn more fat during zone 2. Is that

correct? Relatively yes. But the problem with that claim is zone 2 is in that minimum intensity where like you're just accumulating volume but it's not actually doing anything and what promote

greater fat oxidative capacity actually come from this exercise. And the reason people care about zone 2 right now is based on what elite athletes do. Are you

saying that zone 2 movement was actually built on culture and not science? Yes.

And that's a problem. big theme within my PhD has been like, let's see if that claim holds up. So, that was my why I'm interested in mitochondrial health and using exercise to promote those

adaptations. Well, what about fasting? I

adaptations. Well, what about fasting? I

was under the impression because of prominent health podcasters, etc. say that fasting activates this pathway. I

found out wasn't true. Fasting is an energetic stress for rodents, but it's not for humans. Who knows if fasting is activating autophagy, which you hear all the time. So, you're saying that fasting

the time. So, you're saying that fasting doesn't elicit the same response in humans as it does in rodents.

Correct.

What's your theory on V2 max and longevity and then cortisol?

There's probably so much nuance to what I'm about to say. I'm Louise Nicola and this is the neuroexperience.

Christie, so you have posted research that challenges the notion of zone 2.

And now zone 2 is this infamous zone that we've heard about all over social media. So, can you break down what your

media. So, can you break down what your research found and what exactly is zone 2?

Yeah, I'll give some background of our motivation for um we wrote a paper, a narrative reviewing the evidence for zone 2 for certain claims that I had

been seeing online on social media on popular health podcast etc. That really started back in like I think that started coming out in like 2018. And I

am an avid podcast listener. I was

taking this information to heart and I was thinking like, oh, um, like I was I was hearing claims specifically that zone 2 training is this optimal intensity for improving our

mitochondrial health. It makes us more

mitochondrial health. It makes us more metabolically flexible, able to burn fat when we're at rest or during exercise, etc. And all those things are great and we want those because they're associated

with better metabolic health and then thus chronic disease risk goes down. Um,

so that was my why I'm interested in just mitochondrial health and using exercise to promote those adaptations.

But there was this strong narrative that oh, zone 2 exercise does that and it does something differently than high intensity does and we kind of use zone 2 training as like for mitochondrial

efficiency, which that doesn't really mean anything online. Um, and then we use like high intensity to improve our V2 max or something. And so basically I

brought the idea of zone 2 to my PhD supervisor and initially I was even thinking of studying zone 2 training cuz I was like we we're we're a lab that studies mitochondrial adaptation. So I

was like why don't we use zone 2 training and my supervisor was like what is zone 2 training? Like zone 2 training is not a concept necessarily in exercise physiology. That's not

physiology. That's not the way that we define exercise intensities is not zones. It's exercise

intensity domains and there's three of them. So we have our moderate intensity

them. So we have our moderate intensity domain, our heavy intensity domain, and our severe intensity domain. And they're

defined by very clear physiological responses to those exercise intensities.

And it's a way to just characterize exercise intensities based on actual physiology. So I'll cut you off there

physiology. So I'll cut you off there for a second. So we hear a lot about zones. We've got zone one to five,

zones. We've got zone one to five, right? which is starts with your zone

right? which is starts with your zone one where technically where we're just sitting down. Right.

sitting down. Right.

Okay. And then we go all the way up to zone five which I always describe on the podcast as the death zone when you're going really really hard out. But what

you're saying is that physiologically we in exercise physiology standpoints we only have three real domains. Correct.

And are they dictated by heart rate? Are

they dictated by lactate thresholds?

Right. So there are the reason we have these three domains is because there are clear demarcations of what sets those boundaries. Whereas zones there's no

boundaries. Whereas zones there's no real yeah you can't zone one versus zone 2 or zone 3 versus zone 4. It's kind of just like oh the upper half of the heavy

intensity domain or what have you. Um so

the way that we demarcate these domains is based on lactate. That's one way. Um

you can also use ventilation. So we have a ventilatory threshold that should correlate well with our first lactate threshold. So under our lactate

threshold. So under our lactate threshold is a moderate intensity and that's where zone 2 sits just below our first lactate threshold.

And then you get into the heavy intensity domain which would be I think this is what people think is zone 3 and zone 4. And once you're at the upper

zone 4. And once you're at the upper boundary of zone 4, you get to something called your critical power. Um, and or your maximal lactate steady state or

your maximal metabolic steady state.

It's essentially just anything below that threshold, you reach a set a steady state of ventilation, lactate, etc. So,

if you kept a constant power output or running speed, your lactate shouldn't keep going up. If you continue duration, it should reach a steady state. But

above that, above that critical power, you if you continue increasing duration, your lactate is just going to skyrocket.

You're in the severe intensity domain.

You can only exercise for minutes.

Um, but whereas below that, you can sustain a continuous bout of exercise without having to stop or without having to use intervals, which you would use in the severe intensity domain. Um, so

there are just clear physiological thresholds and things going on in our muscles, in our body that that allow us to make those boundaries that don't apply to all these zones. The zones

really come from the training world, the endurance training world. Um, and then now we're just trying to map the two on top of each other and they don't really mesh that well. Although I think we can

define zone 2 as that upper boundary of the moderate intensity domain that just falls right below your lactate threshold because for example a popular definition

of zone 2 is around 1.7 to 2 millmer of blood lactate and that that 2 millmer typically defines your lactate threshold.

Yeah.

Um and not many people are actually measuring that when they're exercising.

No. So, are you saying that this whole zone 2 movement was actually built on culture and not science?

I when it comes to the general public, like the the application that we're now taking from endurance athletes and trying to apply it to just everyone for general health, I think that yes, it's a cultural movement and it's not based on

science. Even in the endurance world, we

science. Even in the endurance world, we don't have many. So, this was a big conclusion from our review was that we really don't have any evidence for zone zone 2 exercise or zone 2 training

studies to say that it's eliciting these mitochondrial adaptations that apparently the whole online world thinks that it's doing and you'll see everywhere like, oh, you do zone two training to improve your mitochondria.

Um, there's very limited evidence for that. Um, and then when you compare what

that. Um, and then when you compare what evidence is available to higher intensities, higher intensities always wins. If you're going to do an equal

wins. If you're going to do an equal bout of like the same training volume or the same volume of exercise at a lower intensity versus a higher intensity, you're going to get a more potent signal

for mitochondrial adaptations with that higher intensity. Yeah, I've always

higher intensity. Yeah, I've always believed that too. And it makes sense physiologically when you actually understand how are we producing energy and we'll go into that. But I think one

of the main reasons why people, women especially, are somewhat um gearing towards zone 2 is a it's effortless.

It's been marketed as just get on the treadmill light. you know, you be able

treadmill light. you know, you be able to hold a conversation with somebody else. Generally at that 60 to 65% of

else. Generally at that 60 to 65% of your maximum heart rate, which is in and of itself controversial because who on earth knows what that is without a true

V2 max or V2 peak understanding what their measurement is, right? So, how do you know when you're on a treadmill that you're going at that pace? So, it's

generally marketed as, you know, break a sweat but also maintain a conversation.

So a lot of people are doing this because they want to get into that fat burning zone. So zone 2 is sold as a fat

burning zone. So zone 2 is sold as a fat burning zone. You burn more fat during

burning zone. You burn more fat during zone 2. Is that correct? Relatively yes.

zone 2. Is that correct? Relatively yes.

But the energy expenditure of zone 2 is just absolutely lower than you would be at a higher intensity. And you're still going to be burning fat at a higher intensity. You're just now contributing

intensity. You're just now contributing more from carbohydrates as well to supplement energy demand. Um, and then eventually you do reach a high enough intensity where fat oxidation goes down

and carbohydrate oxidation goes up. Um,

but yes, so relatively you're burning more fat in zone 2, but it doesn't mean that you just like shut off fat metabolism when you go into higher intensities. And this is actually

intensities. And this is actually something that even within the exercise science community um, is not really talked about because at high intensities, you're still actually

breaking down atapost tissue. So we

think that we reach this certain intensity where fat oxidation goes down and carbohydrate takes over. However,

when you look at like glycerol levels in your blood at high intensities, glycerol is a marker that you're breaking down triglycerides and that goes up. And then

after exercise, triglycerides go up in the blood because or non-sterified fatty acids rise after exercise once blood flow resumes to our splanic like our

splenic blood flow and now they're released into the blood. So all of this is to say is that we're actually still breaking down fat during high intensity.

It's just like trapped inside our atapost tissue until we stop exercise and then it enters the bloodstream. We

think of high intensity as like, oh, we're just burning carbs, but our body is still breaking down fat and releasing it just after exercise.

So, I want you to imagine I'm a 15year-old right now. Okay?

I want you to explain. So, when somebody gets off a treadmill and they say, "I just did my 1 hour of zone 2 training," what are they actually doing?

I mean, it depends on if they're actually doing zone 2 because there's a high chance that they're not in zone 2.

So, one big observation I've made over the years working in our exercise lab is that moderately active, even like recreationally active, semi-trained

people, have very low lactate thresholds, and if they were to get on a treadmill and start running, even at like a very low um pace, like a slow

pace, they may very well be above zone 2. So, I actually just don't think

2. So, I actually just don't think people are doing zone two if they're like running. Uh, on a bike, it's

like running. Uh, on a bike, it's probably easier to stay in zone two because it's just easier to go at a lower intensity. Um, but so zone 2 could

lower intensity. Um, but so zone 2 could be just like a brisk walk for somebody.

Depends on how fit you are.

For sure. Yeah. Yeah. By the way, I want to interject here. I consider myself semifit, right? I I was very fit back in

semifit, right? I I was very fit back in my day. I was a I was a triathlete,

my day. I was a I was a triathlete, right? Mhm.

right? Mhm.

Uh we did a lot of like lactate testing, a lot of zone 2 and a lot of um V2 max testing.

Nowadays, um me I do if I was to test my lactate levels getting on a bike, let me tell you just like it shoots up. My

lactate will shoot up to like 2.9 just with one push. I think to myself, how do other people who are less fit than me think they're doing zone two, right?

When they're probably theoretically in that domain, maybe two as you mentioned earlier, or uh in probably three, zone three and four.

Mhm.

And that's I don't even know what you're doing in those zones, but I know for sure it's not that zone two.

Yeah. And I mean from my perspective I'm like happy about that because I would rather someone exercise for an hour in zone three than zone two just based on how we adapt to exercise in an intensity

dependent manner.

Okay. So that's that's so funny that you said that. Now there's a lot of exercise

said that. Now there's a lot of exercise physiologists right now on you know um on social media which is amazing and there's so much controversy between for some reason the males right and the

females which it should not be that way right uh we we'll go into sex specific differences however you've got this uh you know one female exercise physiologist who is saying get out of

zone three and four because they are the zones that are producing all the cortisol and this is why you shouldn't be going to orange theory or doing hit classes, right?

Uh but you're saying that you'd rather somebody be in that zone 3 and zone 4 or domain 2 as you said. Why is that?

When we look at meta analyses for mitochondrial adaptation specifically, so if we're thinking about mitochondrial content, so we want to grow more mitochondria obviously with exercise and we want them to become less dysfunctional.

Correct.

Yeah. Meta analyses show that there might even be a minimum intensity for which you need to accumulate volume over for you to experience like an increase

in mitochondrial content. And I fear that zone 2 might be below that minimum or be in that minimum intensity where like you're just accumulating volume but it's not actually doing anything. And

that volume matters when you're at higher intensities in my opinion based on these meta analyses um or meta analysis specifically. There's one I'm

analysis specifically. There's one I'm thinking of.

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a lot of our micked studies. So in if you're reading exercise science studies, a lot of it will be micked versus hit or micked versus sit or something like that. And micked just stands for

that. And micked just stands for moderate intensity continuous training.

And because of how much I've done in testing in the lab in recreationally active um individuals, which is typical population in any of these exercise

science studies, uh like 65% or 70% of V2 max, a lot of literature prescribes based on V2 max. I'm going to hedge my bet that that's above zone 2 for

recreationally active individuals. It

might be um zone 2 for a very trained person, but I don't think it's going to be for just an average person. And we

see similar adaptations in V2 max or mitochondrial adaptations. There might

mitochondrial adaptations. There might there some analyses do favor high intensity for things like V2 max. Um but

what I'm saying is that continuous training can elicit similar adaptations but that doesn't mean zone 2. It means

like I'm going for a 60inute jog or something but I'm versus a severe highintensity interval workout but that I'm not comparing HIT versus zone 2. I'm

comparing HIT versus zone 3 or zone 4.

And in that case I do think that a lot of the literature would support the use of zone 3 and zone 4 which for some reason people women specifically are being feared away from but the endurance

I think for this cortisol reason.

Yeah. I don't I don't understand that because cortisol is part of our adaptive response. Like cortisol,

response. Like cortisol, it goes up in the morning.

Part of liberating fuels from our body.

If you're if you want to meet the energy demand of exercise, you have to break down fuels. Cortisol is part of that

down fuels. Cortisol is part of that response. So your body's just doing a

response. So your body's just doing a normal physiological thing to the energy demand and it goes back down. Like it's

not chronic stress. Um exercise induced stress is not chronic stress. Well, what

about the notion of building your aerobic base? Everybody uses the term

aerobic base? Everybody uses the term aerobic base, but what does it actually mean?

Yeah, what does it actually mean is a great question because there's definitely no definition within the literature. Um, like I think it would

literature. Um, like I think it would just have to do like if we were just trying to like guess what determines our aerobic base, it's probably things like mitochondrial content or our

vascularization, our cardiac output. So

all these like both peripheral and central determinants of exercise performance and probably a lot of them that just determine V2 max. um which

people typically uh separate V2 max from your aerobic base, but I think a lot of the determinants are very similar. So,

if you're going to train your V2 max, you're probably pulling up your uh aerobic base.

And there's this is a really old analysis, but there was an analysis that looked at training intensities and improvements in lactate threshold. And

the conclusion of that was that the more trained you are, you probably need higher intensities to pull up your lactate threshold, which okay, let's define for the sake of this conversation

our aerobic base as our moderate intensity domain. So lactate threshold

intensity domain. So lactate threshold is the top of our aerobic base. Let's

say um this analysis showed that the more trained you are, the more you need high intensity to pull up your lactate threshold or improve your aerobic base.

um not push up. So the way we think of zone two is like you're training under like at a low intensity. So you're kind of building your capacity and kind of pushing up your bases or your

thresholds. But my understanding of the

thresholds. But my understanding of the literature is that you want to work out above your thresholds to pull them up instead of trying to push them push them

up. Um, and another big point is that,

up. Um, and another big point is that, so even just getting back to the introduction of this, why people care about zone 2 right now in just like the

health world is is based on what elite athletes do. So, we've we've taken the

athletes do. So, we've we've taken the training practices of elite athletes that exercise, train 20 to 40 hours a week, and they're doing polarized

training. the like the result of the way

training. the like the result of the way that they train results in an 80/20 split of 80% low intensity, 20% high intensity.

Training as you mentioned, how many hours a week?

Yeah. So, say a like a minimum of 20 like if you're a professional athlete.

I was I I'll just cut in there. I was

training 7 days a week around 6 to 7 hours a day.

Oh my gosh.

Yeah.

Yeah.

Yeah.

So, that's way more than 20 hours. But

if you're say let's say you're exercising for you're training for 20 hours 20% of that is 4 hours of highintensity exercise like that's more

than I do probably in a week.

Um so that we're we're attributing their pristine mitochondria and their great metabolic health to that 80% of low intensity where it could very well be

that 20% that's actually inducing those adaptations. And the 80% is I don't know

adaptations. And the 80% is I don't know facilitating the ability to do that 20%.

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order. A lot of this has to do with periodization as well, but also what are your goals? What I think uh a lot of

your goals? What I think uh a lot of people are missing is what why are you training in the first place, right? um

you train differently if you want to train for a marathon, you know, or if you're just training for longevity, whatever that means, right? But a lot of women are and and men, you know, like

let's just say in that age bracket of around 40 to 55, and they've been told you need to train for 20 minutes a week to increase your zone 2 uh to increase

your V2 max, and then you need to train, you know, in zone 2 for 3 to four hours, and then you need to do your resistance training. So, everybody doesn't

training. So, everybody doesn't understand that you need to be it's individualized. Like, what are you

individualized. Like, what are you training for? If you're training for a

training for? If you're training for a marathon or you're training for fertility, two completely different training programs, but what you're saying is for overall health and longevity. I think that's what you're

longevity. I think that's what you're talking about, right? Because we're

talking about mitochondrial adaptation.

Okay. Mitochondrial biogenesis. Are you

saying that we should be if that's the whole sole purpose, we should be sticking to more zone 4, zone 5? I just

think that we're over complicating exercise prescription. I for someone in

exercise prescription. I for someone in the general public that's exercising maybe 30 to 60 minutes, not even every day. Like think most people are maybe

day. Like think most people are maybe exercising like 4 days a week. And if

they're doing 80% of that in like let's say they're cardio, maybe they lift two days of those and then they have four days of cardio. If they're doing 80% of that in zone 2, I don't think it's going to be doing much for promoting

adaptation because that's such a small volume where they would benefit more from having some probably intervals and then supplementing that with if they want to do if you want to do continuous

exercise. I think people need to feel

exercise. I think people need to feel more comfortable with zone 3 and zone 4 because I think that that is people think of it as like this gray zone or like this no man's land um because it's like incurring stress without adaptation

or something. I don't know. I don't

or something. I don't know. I don't

actually know the argument, but I uh I think it's a good zone. I do think that it's all just a spectrum. The closer we get to that high intensity, the better, but then we'll have to do intervals. So,

you have to be if you want to do continuous exercise, if you want to go for a 10k run, um then you're going to have to stay at a lower intensity. But

if you're in zone 3 or zone 4, it doesn't matter. Who cares? Um, so I

doesn't matter. Who cares? Um, so I think that we're just over complicating the and the need for this like period periodization or this training intensity

distribution for members of the general public. If you're an an elite athlete, I

public. If you're an an elite athlete, I don't think this conversation like applies to you. I I think we're talking about someone like you and me who care about health and we have like maybe an

hour to dedicate to exercise a day. Um,

and in that case, I think just pushing yourself like one, I think you need to be doing what you enjoy because you're never going to stick to something longterm for the rest of your life, which I think everyone needs to do

exercise for the rest of their life. Um,

so you need to find something that you'll actually stick to. Two, we need to add in resistance training into there in there somewhere. So, we're not just speaking cardio. So, if we only have

speaking cardio. So, if we only have like a select few days to do cardio, then go hard. Like, don't I don't think any of that has to be dedicated to zone 2. And when I say go hard, it's go hard

2. And when I say go hard, it's go hard for how you feel that day. Like don't

deliberately stick to a low intensity because someone told you online or you read it in a book that like, oh, I have to do zone 2 training for my mitochondria. Um, I think you should

mitochondria. Um, I think you should always just go as hard as you can for that day. And if you're only doing

that day. And if you're only doing cardio like three to four days a week, I don't think we have to worry about recovery. Like you can do zone 3 plus

recovery. Like you can do zone 3 plus every time you do do cardio. um where

people think like, oh, you can only handle one or maybe two HIT sessions a week where that's not true. Like even

from a glycogen depletion standpoint and like recovery standpoint, uh there was a study that um did used the three intensity domain. So there was a

intensity domain. So there was a moderate intensity which is like zone 2, a heavy intensity, which is the 34, and then a severe, so that's your

your in your V2 max. Yeah. In zone. Um,

and they exercised them to fatigue. The

severe intensity, they didn't even really deplete that much glycogen because you're only exercising for like minutes, like maybe like 8 minutes. They

could last not even that.

Um, in the heavy intensity domain, they fatigued at around like 40 minutes and they depleted a good amount of glycogen.

But it was really interesting the zone two, so the moderate intensity domain, they they fatigued at like 240 minutes.

So, it was like a really long bout of exercise, but they like dramatically decrease their glycogen stores, which we think of zone 2 as like not depleting glycogen, but you do actually deplete

glycogen. So, I was thinking about this

glycogen. So, I was thinking about this just today like on the subway coming here, I was like, we think about zone 2 as not really needing that much recovery, but according to that study, like you're depleting a lot of glycogen.

It makes sense physiologically.

Well, yeah, you're exercising for like a like a long time. like you're burning mostly fat, but like if the duration's long enough, you're still going to you're still going to be burning carbs.

So, we've heard a lot around to exercise fasted or not. You know, if you exercise fasted, you go into the fat burning stores and you burn fat more

efficiently. Is this true?

efficiently. Is this true?

Yeah. Yeah. So, I guess this comes back to your question or your few questions ago about like burning fat during zone 2 and like the reason we would even want to burn fat during exercise, which

applies to fasted exercise as well.

And I think this comes like the idea that like burning fat makes you a better fat burner because like you're just pract like you're training your body to do the thing that you're forcing it to do.

However, the adaptations that promote greater fat oxidative capacity actually come from exceeding your capacity. So

this is applies to mitochondrial adaptations as well. Like you're going above what your your body is comfortably like can comfortably handle so that you're sending signals that you need to

adapt so that the next bout of exercise you're better able to handle that stress of exercise. And I think about that from

of exercise. And I think about that from a fat oxidative capacity too. And hey

I'm like I do exercise fasted. I have

for many many many years and I was always bought into like oh I'm I'm inducing greater adaptations and I think there's something to that. There's

a whole there's a lot of literature that you could make a good argument even my own research um that if you train fasted you may be inducing greater adaptations

that promote or are markers of greater fat oxidative capacity. And from a metabolic health perspective, there's some studies showing that fasted exercise versus breakfast fed or

carbohydrate fed um actually improves like things like glucose control to a greater extent. So there is something to

greater extent. So there is something to like burning your stored fuels or induc like that flux through the system that's not coming from exogenous sources like you're using your stored fuels. There

might be something to that like turnover from a liver, from a muscle, from a whole body perspective that's good for metabolic health and for potentially inducing some adaptations, but there's also evidence to the contrary. So, I

don't have like a strong stance other than the studies that exist in favor and the studies that exist not in favor. But

I do want to get back to the fat burning part because we do think that like, oh, I'm I'm going to do a low intensity so I burn more fat or I'm going to train fasted because I'll burn more fat. And I just don't

think that there's strong evidence to suggest that the fuel you're burning during that bout of exercise is making you better at burning that fuel that you

burned during that bout of exercise. Um,

so we just need to think like reframe how we think of adaptations. It's just

like you want to it's kind of like resistance training like you're you want to lift almost to failure so that you tell your muscles to grow.

Exactly. Adaptation stimulus. Yes. of

enzymes, mitochondria, etc. You want to yeah, stress the system, we respond to stress. That's how we adapt. Um, and so

stress. That's how we adapt. Um, and so when we tell the system like, oh, we're going be above and beyond what you can handle right now. Those that's the signal to say like build more so that

next time it's easier.

So, one of the newest hacks that I have been doing, it's not going to be new for you, it's new for me, is I have started to introduce probiotics into my system.

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actually said that you shouldn't exercise females specifically uh in permenopause that you shouldn't exercise fasted. And then you've got Stuart

fasted. And then you've got Stuart Phillips who I've had also had on the podcast saying that there's no evidence for that and you can exercise. You can

eat before you exercise if you feel good or you don't have to. It doesn't matter.

Right. So it definitely does matter. I

don't like there's no female specific argument against fasting before or fasted exercise. You have when you go to

fasted exercise. You have when you go to bed at night when you sleep, say you've gone 12 hours without eating, your muscle glycogen is untouched. You have

not there's no decline. you when you went to bed from when you woke up is the exact same. Your liver glycogen is

exact same. Your liver glycogen is slightly depleted upon waking. And so if you go into now a bout of exercise, your if you're doing high intensity, for

example, you're really just relying on muscle glycogen. Like you're not um

muscle glycogen. Like you're not um because depending on the demand of exercise, like you're using your local fuels, you're not relying on blood glucose as much if if you're doing a super high intensity about but if you're

going to do a low intensity, then you're burning more relative fat. And then your liver is just going to take over and make sure that your blood glucose is maintained during that bout of exercise.

But you will burn relatively more fat in the fasted state during moderate intensity exercise. But as soon as you

intensity exercise. But as soon as you go into high intensity, so if you were going to do like a CrossFit workout or an Orange Theory fasted, um there might not actually be that big of a difference between fuel

utilization, unless you're in like a lower intensity because once we reach a certain intensity of exercise, the fuel utilization is actually the same between fed and fasted cuz like I said, you're

relying on local stores and your muscle glycogen is the exact same. And then I think this comes back to your cortisol um mention of cortisol from zones three and zone four from earlier and that's

kind of used as a reason women shouldn't train fasted because it's the morning your cortisol is higher in the morning and now you're fasted so potentially you're increasing more cortisol because

you're like I said liberating fuels because that's a natural response and now you're exercising and you're going to be inducing cortisol and it is true that fast exercise can elicit greater

increase in cortisol than if you were fed. But I do think that just is because

fed. But I do think that just is because you need to break down your stored fuels. And so if you're in the fasted

fuels. And so if you're in the fasted state and so uh it doesn't mean that it's like I said contributing to chronic stress. It's just that you you need that

stress. It's just that you you need that greater signal to break down fuel and then it comes back down post exercise.

Um so it's fasted fed regardless. um

you're going to elicit a bit of a cortisol response, but I don't see an argument for encouraging women to only train in the fed state or discouraging women to train fasted if that's what

they prefer cuz I like training fasted.

Like I don't really like eating before I exercise. And I'm not scared to exercise

exercise. And I'm not scared to exercise in the fasted state for some sort of female hormonal health perspective. If

you have a really high training volume, this applies to both men and fe and women. um training fasted if can put you

women. um training fasted if can put you into just an overall energy deficit. And

in that case, if you're an athlete training for hours and hours, you can't you basically just like you get into you dig yourself too big of a hole that you can't climb out of over the course of the day if you're training fasted in the

morning. And in that case, then you

morning. And in that case, then you could be potentially leading to low energy availability. And that's a

energy availability. And that's a problem. But it's not because of the

problem. But it's not because of the fasted exercise per se. It could be just because now you can't catch up and you're in an energy deficit for the rest of the day. Yeah. Um and that's

problematic and I totally think that if you that's you then eat before you exercise or consume some sort of like liquid or gel during exercise.

Can you walk me through a piece of research that changed your life? Ooh. Oh

my gosh. because I've got one like I know for me uh what you know I read a 2011 study from Eric Senetal which basically was a systematic review of all

of the available literature to figure out what benefit does resistance training play on the brain and that I don't know what year I read that but

that that was you know the pinnacle for me and that paper is what actually dictated the rest of my my academic career career. You know, my entire

career career. You know, my entire doctoral thesis is literally looking at uh resistance training on MCI patients and that changed my life.

Wow, that's a loaded question. I'll just

like pick let's just talk about like some some pieces of research you found that's some of your favorites.

Can I just can I bring up my own research?

You can anything that you've read? Yeah.

My first um my first study that I did in in my lab was a systematic review and it looked at the fasting response in humans versus rodents. And I was under the

versus rodents. And I was under the strong impression that fasting was this energetic stress and we adapt energetic stress the same way we do in exercise

and that should increase um that should activate something called AMPK and that leads to a downstream signaling cascade that should lead to things like mitochondrial biogenesis and activate

longevity genes etc. Anyways it's good for health it's good for whole body metabolism. Um so I was under the

metabolism. Um so I was under the impression because of very prominent health podcasters etc that say that fasting activates this pathway and

giving a mechanism to a behavior um that was what was I found out wasn't true and I think this comes to the zone two thing too this I mean a big theme

within my PhD has been like is that true let's look into that let's see if that claim holds up and when I I've published that fasting review and I

was really proud of it and it got a lot of attention and basically fasting is an energetic stress for rodents but it's not for humans if we're doing just like a 24-hour 36-hour fast like it's not

activating these pathways that we think it is and then therefore not and AMDK is like an upstream signal for autophagy for example and if that's not activated

then who knows if fasting is activating autophagy which you hear all the time so anyways that was like one claim that.

So, you're saying that fasting doesn't elicit the same response in humans as it does in rodents?

Correct.

So, why why this huge push for fasting, you know, going on a one two-day fast?

Yeah. I don't know. I like I said, we're giving it mechanisms based on like mechanistic data in things like rodents um or just like giving I this is a problem with social media is that like

we want to tell a mechanistic story so that individuals buy in. And I think that's with the zone two. It's like zone two, we burn fat, so therefore we use our mitochondria and thus we're

improving our mitochondria and then we get better at fat burning. And like you can buy into that, but there's no way for you to prove it. So you just kind of have to have this like faith belief in that it's doing something. You know,

when you do your PhD, you really realize that, you know, just stringing a bunch of words together in a sentence and throwing in a mechanism there, you think

that you're, you know, you can definitely move mountains and manipulate an audience to believe into your theory, which is what a lot of these mainstream

uh social media influencers/docctors have done. But when you actually dig

have done. But when you actually dig through the data and you do the RCTs, you realize it doesn't make sense, right? what you're saying does not make

right? what you're saying does not make sense. And I see this, there's a, you

sense. And I see this, there's a, you know, Instagram is just flooded with this every day.

And I think to myself, how can you stand there and say this when you have no data to back it up? And

by the way, I have this new headline that I want to put out. Right? Tell me

if you agree.

Okay?

Right. It's very simple.

Humans are not mice.

Yeah. Okay.

That's a good one. So, you and I both have a um I know I'm going off track here, but we we share somebody in common, Dr. Tommy Wood, who is one of my academic adviserss. Love him. And he

academic adviserss. Love him. And he

works primarily with rodents. He was the one who said this, you know, he came on the podcast back in December. We had a coffee and he's like, Louisa, he's like, we're actually talking about peptides.

Okay.

Okay. I'm not going to go there today.

And he's like, "Please," he's like, "A lot of the a lot of literature does not correlate to humans because we're not mice. We are not rodents." Do you agree

mice. We are not rodents." Do you agree with that?

Oh, 100%. And that was like my fasting review really just hammered that home for me because like I learned about the differences in metabolic rate, the differences in like the way body weight

changes during a fast. Humans lose like 2 to 4% after a 24-hour fast.

um rodents lose like 50% of their body weight or something crazy and their muscle glycogen depletes within like a 12-h hour fast and it's just so radically different that like applying

applying the research in rodents to humans. It's obviously needed and it

humans. It's obviously needed and it starts us off and and allows us to create human studies and study design, but until it's shown in humans, like why

why are we applying things that because it's fun and it sells books and it sells supplements. Yeah.

supplements. Yeah.

What's your theory on um V2 max and longevity? Because you know V2 max is

longevity? Because you know V2 max is one of the things I care about, right?

And there is a strong correlation between V2 max and brain health. But

what does the data say for V2 max and longevity?

Yeah. I mean I'm not an expert in this area at all, but I mean it's correlated with reduced risk of chronic disease, which is therefore going to health because it's a marker of just our whole body physiology. It means that we have

body physiology. It means that we have good blood flow. It means we have good vascular vascularization. It means we

vascular vascularization. It means we have a good heart. It's it's just like a good marker of like whole body systemic metabolism. It means that we can extract

metabolism. It means that we can extract oxygen from our blood and we can use it in our cells. It's just a it is a really good like whole body marker. Um and

yeah, I mean it's obviously correlated with longer I mean up until a certain point. I don't know, there's some like

point. I don't know, there's some like elite athlete data that kind of contradicts this, but um yeah, like it's associated with greater um reduced risk of mortality. So,

of mortality. So, yeah. And how you're utilizing oxygen,

yeah. And how you're utilizing oxygen, but all I think uh it really comes down to you're in a mitochondria lab, right?

Do you think that a lot of diseases come down to the efficiency of the mitochondria?

I think mitochondria Yeah. mitochondrial

health um content and function is certainly associated with many diseases because of how critical our mitochondria are for metabolism and then how critical

metabolism is for just every process in our body. So that's why it's probably

our body. So that's why it's probably related to insulin resistance but also Alzheimer's and then also I don't know everything. It comes down even to

everything. It comes down even to fertility, right? You know, in in in

fertility, right? You know, in in in females and in males, you know, we you know, I speak about this often. I've

been on this whole uh uh mitochondria rampage this week with the podcast, but you know, when it comes down to it, it's like, how can you refute that a, you

know, 25year-old female with really poor metabolic health, you know, and a high AMH, which is a marker of uh egg quantity, I believe, um can't get

pregnant. But then you've got this

pregnant. But then you've got this 42year-old really low AMH but really great markers of mitochondrial health and uh and metabolism and can fall pregnant naturally. And that's where I

pregnant naturally. And that's where I think that mitochondria is really interesting because you know it dictates how we use energy effectively. Uh what I

don't know yet is well we can't just go and draw blood and figure out you know it doesn't say on a on a CMP mitochondrial health you know we can't really measure it can we

no unless you get like an invasive if you get a muscle biopsy which actually so my current study right now that is in collaboration with Dr. Tommy Wood and Dr. Andy Galpin. Um, a portion of our

study I'm stealing for my PhD dissertation and I'm looking at whether lactate threshold correlates with u mitochondrial content in across

individuals uh older, younger, lean, overweight. Um, so hopefully diet like

overweight. Um, so hopefully diet like separating health status and seeing if we can use lactate threshold as a marker of mitochondrial content because that is a way that zone 2 is almost advertised.

It's like a if you if you know your zone 2, it's a functional assessment of mitochondrial health. And that is a claim I've heard

health. And that is a claim I've heard that I don't see hasn't been really studied within the literature. So, I

hope that I address that with my research. Um, but that would be really

research. Um, but that would be really cool. So, if if we can just do like a

cool. So, if if we can just do like a graded exercise test, which means just it increases in exercise intensity until we find our lactate threshold. Um and we find that that

yeah that threshold for which basically I'm the power output associated with our a certain lactate level. Um if that is associated with how

level. Um if that is associated with how much mitochondria we have in our muscle then that could be that literally could be a functional assessment of mitochondrial content. Um so I mean I

mitochondrial content. Um so I mean I hope my research one day shows that you keep saying the word lactate. M uh

you and I probably uh have we have the same definitions of it but um probably think about it very differently cuz I think about it as a phenomenal fuel source for the brain. Can you just

explain what lactate is?

Yeah. So the way I view lactate and why I'm using it in my research and I've done lactate thresholds in all of my studies is because I think it's a really cool window into the bioenergetics of

our muscle. Um, so when we're

our muscle. Um, so when we're exercising, as we increase exercise intensity, like I said, we're going to start burning um more and more carbohydrate, we're going to start

oxidizing more and more carbohydrate.

And as we oxidize carbohydrate, a necessary product of glycolysis is that we're going to make some lactate. Um,

and so, so some of that pyrovate is going to be make turned into lactate, and some of that lactate is going to be exported into our blood. Some of it's going to be used by nearby muscle

fibers. Um the the what gets exported

fibers. Um the the what gets exported into the blood can be used by our brain, our heart, etc. other tissues, but we can measure that in real time. The the

blood uh concentration of blood lactate.

And while it's not it is just a snapshot in time. So it doesn't tell us about

in time. So it doesn't tell us about flux. It doesn't tell us about import

flux. It doesn't tell us about import into the blood or export into the blood, but it does give us a little snapshot during exercise. Um, and so it's a

during exercise. Um, and so it's a marker of carbohydrate metabolism basically. So if you're, yeah, if you're

basically. So if you're, yeah, if you're burning more carbohydrate during exercise, then you're going to be producing more lactate and eventually you're going to reach failure and your lactate will be through the roof most

likely. Um, and so I think of lactate as

likely. Um, and so I think of lactate as just a really cool marker of fuel substrate utilization, even though it's very indirect. But I just I like it

very indirect. But I just I like it because it's more accessible than something like a metabolic cart where you have to wear a mask and that will tell you your whole body fuel subst utilization and how much carbs you're

burning, how much fat, but that's just really not accessible from the general public. Whereas like a lactate meter is

public. Whereas like a lactate meter is more. No, not many people own a lactate

more. No, not many people own a lactate meter, but it's definitely more accessible than It's actually really expensive, those lactate strips.

Oh my gosh. I just ordered Yeah.

thousands of dollars worth and I did the math and it was like $3 to $4 per strip and I was like, are you kidding?

And then they actually expire.

Really?

I think they expire. Yeah.

Oh, wow.

The actual lactate meter I got, lactate plus I believe it was around $400. But I

was like, oh, that's expensive. But then

the strips are what cost me.

Yeah.

Um I want to ask you if you were to redesign how the population thinks about cardio, what would you say?

I think the general population thinks about cardio as just for weight loss or for fat burning. Um and just yeah, like they're like, "Oh, I want to lose weight. I'm going to start doing I'm

weight. I'm going to start doing I'm going to start running. I'm going to get on the treadmill." I think of exercise as basically like our daily metabolic reset. It's like my body doesn't know

reset. It's like my body doesn't know what to do with the foods that I'm going to eat and the nutrients I'm going to eat unless I stimulate my muscles and I start transllocating glute 4 to the cell

membrane so that I can take in glucose out of my bloodstream. And so I think of it I think of exercise as our like activator of teaching our body how to

use fuels. And without that, that's what

use fuels. And without that, that's what can lead to metabolic dysfunction because we're now declining mitochondrial content. Our efficiency is

mitochondrial content. Our efficiency is reducing and now it's leading to insulin resistance and blah blah blah. It's

gunking up our cells and uh etc. So I wish people viewed exercise as just like a daily hygiene thing like brushing your teeth where it's like yeah your daily metabolic reset. kind of like that like

metabolic reset. kind of like that like where it's like you're you're about to eat and you your body needs to know what to do with those fuels and exercise does that. It sensitizes our like when we

that. It sensitizes our like when we exercise our muscles are now sensitized to amino acids so we can bring them in.

We can we can start building muscle but we can also start using glucose better and we're more insulin sensitive and those things are so important for just long-term health and just maintaining

maintaining good metabolism which is obviously going to be associated with disease. So, you're saying that we

disease. So, you're saying that we should all be exercising every single day, even if it's just moving our body, getting on the treadmill even for 10 minutes.

Yeah. We don't have to like structure and like we don't need structured exercise every single day, but we should certainly be moving our body every single day. I feel like sedentary

single day. I feel like sedentary I mean, I'm sure you've had so many people on this podcast say that like a sedentary lifestyle is a disease.

Yes. It's terrible.

And exercise is medicine.

Exactly. And it's not even that exercise like exercise it's good obviously it does a it benefits you but it also protects you from a sedentary lifestyle.

So it's it's not only just like retract like bringing you like preventing that but it's al it's bringing you forward as well. But I think of yeah like sedentary

well. But I think of yeah like sedentary lifestyles as like you're doing something harmful. So now you have to

something harmful. So now you have to exercise to combat that.

Yeah. And so what would be the best in your um in your experience the best exercise prescription for people who just want to increase health span and

lifespan like they they want to live a long life. They don't want to go crazy.

long life. They don't want to go crazy.

They don't want to be a they don't want to do a marathon. They don't want to be a bodybuilder. They just want to feel

a bodybuilder. They just want to feel good, feel energetic. What's the best exercise prescription for that? And

don't worry about resistance training.

Okay. If we're just speaking cardio, I don't think there's a best. I don't

think that there's a onesizefits-all.

The the most recent meta analyses would suggest that training volume and training frequency is very important for things like V2 max and for mitochondrial

adaptations. So frequency meaning that 3

adaptations. So frequency meaning that 3 days is better than two, four days is better than three, 5 days is better than four. Um and so staying consistent I

four. Um and so staying consistent I think is really important. intensity I

think is very important. Um, and what that means like that could be like I said just like I think it's just accumulating as much volume above zone

two as you can. Um, and and what that is, it's going to depend on the individual and what they what they enjoy. But I think that the consistency

enjoy. But I think that the consistency is very important. I think that intensity is important. Um, and then just trying to hopefully find something that's fun. Like it's exercise. Like

that's fun. Like it's exercise. Like

it's it kind of sucks that we biologically don't want to exercise but we have to. So we have to figure out a way to build it into our life that we can sustain for the rest of our life.

Um, so I think that's the behavior change is really probably the hardest part. And from there, if you want to

part. And from there, if you want to optimize, I think that doing some I do think that continuous exercise and what I mean by that is like not intervals

like being able to go for like on the bike steady state um in those zones three to four etc. And then doing intervals um I think are really important. So pushing yourself to the

important. So pushing yourself to the point where you can't sustain it for more than four to five minutes. you have

to do it in intervals because it's such a high intensity. Um I think that that's a really potent stimulus for adaptation and it's also just the best use of your time. You're getting the best bang for

time. You're getting the best bang for your back.

That's what I say. Yeah. I do a lot of mine um on the uh stair master because you know I live in Manhattan and like it's been it's about to we're having a snowstorm today. It's raining.

It's like I can't get outside that much.

But I love that stair master.

I I've become you know utterly obsessed with it. that and sprint intervals as

with it. that and sprint intervals as well. And my prescription is the same.

well. And my prescription is the same.

I've because I took my triathlon career so seriously. I never missed a session.

so seriously. I never missed a session.

I woke up every single day at 5:00 a.m.

I took it so seriously and I don't want to be in that phase of my life anymore.

I want to be in a a more mature phase where I I fall I I am in love with exercise. I was in love with triathlon

exercise. I was in love with triathlon training as well and the variety that it gave, but I don't want to be that prescriptive, right? I want to be able

prescriptive, right? I want to be able to do what I have to do. And I I I work out every single day.

And sometimes, listen, I'll be really honest. Uh sometimes I can only get to

honest. Uh sometimes I can only get to the gym for 15 minutes, right?

But I've still done it and I've lifted my And I know if I've got 15 minutes, I'm just going hard out, right? As hard

as I can.

Yeah. And I think that's like what's really fun is like I mean I love circuit training. So lifting weights in a

training. So lifting weights in a circuit for time like I have about like I started in CrossFit that was really my like start with fitness and so I've

continued just training in that style for the last decade and I do think that it's such a great way to both get cardiovascular responses but then also be resistance training at the same time.

I don't think it's necessarily the best for either but it's something I can stick to and do every day. So,

devil's advocate, uh, 73y old female says, "Well, I'm I'm too scared to get into the zone 5. Um, I don't know how to get there. I can't get there. My knees

get there. I can't get there. My knees

hurt. I'm you know, what if I have a heart attack?" Like, how do how does the

heart attack?" Like, how do how does the elderly population stick to this?

Yeah. For someone who is very, I'm assuming an elderly 73-year-old who's may be coming from a sedentary background is going to be unfit like untra untrained from a physiological

perspective. And in that case, high

perspective. And in that case, high intensity is brisk walking. So we have a study out of Queens University that looked at moderate intensity versus high

intensity and and followed they were older um obese individuals I believe and there was greater results with the high intensity but the high intensity was

breast walking. So it was like just a a

breast walking. So it was like just a a a nice slow pace walking. I I can't remember the actual prescription like how many times a a week etc. um versus

high intensity like it was the the verbiage was high intensity but then when you go to the methods it says brisk walking. So if you are really untrained

walking. So if you are really untrained brisk walking is high intensity for you and that if you're going to take that into the real world you could just go

lamp post to lamp post a bit brisker a bit as fast as you can whatever that means to you and then you take a break and you go a bit slower. That's interval

training for someone who is untrained.

And so I think we just meet everyone where they're at.

We get out of breath when we exercise.

Like we're pushing ourselves. We're

getting uncomfortable like to elicit these adaptations, there is a bit of discomfort. Um so accepting that and and

discomfort. Um so accepting that and and then just trying to find something that that you enjoy. And I think that no matter what fitness you come into

exercise at, so if it's you versus the 73year-old woman, like her brisk walking is probably the same as potentially your sprint training. So, uh, it's meeting

sprint training. So, uh, it's meeting where you're at and not getting so like bogged down by the best prescription and etc., etc. I think we're I think we're over complicating it because like I said

like these when we look at the literature when it's in done in a systematic meta analysis um like we do see like similar adaptations with different intensities and all this

stuff. So um I just think that there

stuff. So um I just think that there isn't going like we're not going to find like this best protocol and that we can get we can do a mix of things and get to

all all roads lead to Rome. Yeah. I um

when I go to the gym, I wear a heart rate monitor and I have a Garmin watch and it's a look, I don't know if it's a it's something that I carried with me

from my my triathlon days. I just can't do that and I don't think that everyone should be doing that. I don't think everyone should be looking at their heart rate, but I do just it's just, you know, embedded in me.

How do you think that people should go to the gym and know if they're in these certain zones?

I think you can tell a lot by ventilation. So, how heavy your

ventilation. So, how heavy your breathing. So, for an untrained indiv or

breathing. So, for an untrained indiv or just like recreationally active, so we're not talking about elite athlete.

So, anyone who's not an elite athlete, um your ventilation is a is could be a good indicator of these like thresholds that I was talking about in the beginning. So, our lactate threshold, as

beginning. So, our lactate threshold, as soon as we're above our lactate threshold, we're going to have more heavy breathing because now we're we're burning more carbohydrates. Our energy

demand is higher. We're our muscles are releasing more CO2. that all these things are triggering the need to breathe at a heavier pace. And so we can tell intensity by how heavy you're

breathing. Um, and so getting to the

breathing. Um, and so getting to the point of where you can't talk during exercise, that's probably in the severe intensity domain. That's where you're

intensity domain. That's where you're doing those V2 max intervals. Um,

anything below that, like you like it it should be challenging to have a conversation because your ventilation is just too high. Why I say not elite athletes is because elite athletes so I

want to get back to these domains and the difference why it doesn't make sense to apply elite athlete research to general public because their domains are

their entire exercise intensity spectrum is almost entirely the moderate intensity domain. So their lactate

intensity domain. So their lactate threshold is so high and then their heavy intensity domain is like this little sliver and then they have their severe intensity domain. So they

probably end up just doing polarized training and 80% in low intensity because it's literally makes up like the majority of their entire intensity spectrum. Whereas someone like you or me

spectrum. Whereas someone like you or me or some someone who's less trained would have their lactate threshold is very low. Their moderate intensity domain is

low. Their moderate intensity domain is much smaller. Their heavy intensity

much smaller. Their heavy intensity domain is much larger and then they have this severe intensity domain. Um so

everything there the spectrum is split and that's where I think that we should be exercising more in those heavier intensity and severe intensity domain.

Um because that moderate is just the absolute intensity associated with that that zone 2 or the moderate intensity domain is so low. Whereas an elite athlete that could be 300 watts on the

bike. For someone in recreationally

bike. For someone in recreationally active it could be 80 watts on the bike.

And that's a completely different it could be a completely different stimulus um to adapt to and that could be why elite athletes maybe do adapt to zone 2 and that it actually is doing something really great for them. Although like I

don't think there's strong research for that yet. Um but why I think that it

that yet. Um but why I think that it doesn't make sense for a recreation active person to be doing zone 2 is because it means such a low intensity.

Like if you're trying to get better at running and now you're trying to do zone two and it means you're just like shuffling along, I don't think that's making you a better runner. Like I think you need to get

runner. Like I think you need to get into a stride that you would run. And

unfortunately that's going to be not unfortunately fortunately it's going to be in zone 3, four, and then if you're going to do intervals zone 5. Um

I don't even remember your initial question but I just went off on a tangent. My last question is, if you

tangent. My last question is, if you could put one sentence on a billboard that every woman exercising right now would see, what would it say?

Every woman.

Ooh, I don't know. I don't do a lot of sex differences stuff. Like, I don't think that it applies really. Like, I'm

I don't change my training.

Did you actually talk about that? So,

you're saying that all of these um exercise physiology studies that we've looked at, are you saying it applies for both men and women? Well, for for zone 2 specifically, like I've seen like claims

that zone 2 doesn't work for women. Um,

but the because of the mitochondrial um density, I think it was a I know what you're talking about. It's was a claim that women don't need to do it because women have more mitochondria than men,

right? It was like, yeah, it's like, oh,

right? It was like, yeah, it's like, oh, women are already metabolically flexible. We always we already have

flexible. We always we already have inherently higher fat oxidative rates, so we don't need to do zone 2. But the

the problem with that claim implies that zone 2 training is good for improving fat oxidation. And like that's like the

fat oxidation. And like that's like the the underlying implication is like, oh, it works for men because they have poor fat oxidative capacity, so they should be doing zone 2, but women shouldn't.

But the problem with that is that it's implying that zone 2 is improving fat oxidative capacity, which like maybe it does, but I'm don't I'm don't think zone 2 is inherently improving fat oxyative capacity. Um,

capacity. Um, but do men have But then to get to the sex differences, um, yes. Like, so women do burn

um, yes. Like, so women do burn proportionately more fat during exercise than men and have like different I'm not super familiar with this literature, so I'm just like going off

like the the basics in and what I think is consensus, but probably controversial. like everything in

controversial. like everything in exercise science. There's probably so

exercise science. There's probably so much nuance to what I'm about to say, but I think it's that females have like more intramuscular triglycerides, greater type one fibers, so we're more

oxidative. We have which are more dense

oxidative. We have which are more dense in mitochondria, so we're burning more fat at the same intensity um as men.

Like we'd be burning more relative fat fat. Um, and then that's somehow being

fat. Um, and then that's somehow being turned into zone 2 training doesn't work for women, which like literally is like taking leaps in literature and making I

don't know puzzles pieces together. Um,

so no, there's I don't think there's any reason that we could say zone 2 works or doesn't work. One, again, the crux is

doesn't work. One, again, the crux is the saying that it works at all. Um, so

that yeah, no sex differences there. I

will put my money on.

And and then when it comes to the way we adapt to exercise, very similar between men and women. Like I think more and more research is coming out showing that females do not respond dramatically

different from men. There might be some slight sex differences, but I'm this is not my area of expertise, but I would I do not think that the the state of the

literature would ever encourage me to change what I do because I'm a female. I

wouldn't I wouldn't do something differently because you're a human.

Yes. I I'm just going to exercise the way a human should exercise.

I really Yeah, I I'm with you on that.

Even in the, you know, myioine research, right? It's And the the only part I

right? It's And the the only part I think where it gets tricky is the estrogen receptor loss. We don't have a lot of data on that, right?

I have no idea. This is beyond my my scope.

Well, but for a billboard, I didn't answer that. I think it would just be

answer that. I think it would just be move your body every day.

I don't I don't have a or for Yeah. for

women. I mean, it's it's gonna be this is gender neutral.

Be happy.

Be happy.

Yeah.

Oh, I loved having you on the podcast.

We're going to link your amazing papers below. Thank you for being part of it.

below. Thank you for being part of it.

Thank you so much for inviting me on.

This was fun.