And the question is well how do you improve your cardiorary fitness right? Yeah I mean >> do you lift weights do you go for runs do you bike what is it that is really good at improving cardiorisfree fitness and that's the question that a lot of exercise physiologists have answered over the last couple of decades. You want to do and engage in what's called vigorous intensity exercise.
So this is the kind of exercise where you're not able to have a conversation when you're engaged in it, right? So, so your heart rate is going up to about 80% your max heart rate. You're not able to really talk.
And it's I would say, you know, it's something that can be done in intervals. So you can do high intensity interval training. So you have these intervals where you're getting your heart rate up, you're doing vigorous exercise, and then you have recovery periods where you're kind of resting.
You're you're lowering your heart rate. you're not doing that max that maximal sort of exercise. And I say this because there have been studies, multiple studies that have shown people that engage in moderate intensity exercise.
So, this is the kind of exercise when you can you're breathy, but you can still kind of have somewhat of a conversation while you're doing it, >> like the stairmaster. >> Like the stairmaster. Yeah, exactly.
Um, even people that are engaging in that type of exercise for two and a half hours a week. So, this is following the physical activity guidelines. 40% of those people can't improve their cardiorespiratory fitness.
And it's like, well, I don't know about you, but like I don't want it to be a coin toss in terms of like if I'm doing that kind of exercise, well, if I have a 50% chance of not improving my cardiorespiratory fitness if I'm doing this. I want the sure thing. And the short thing is you take those people and then you have them engage in highintensity interval training and they're able to improve their cardiorespiratory fitness.
And that's because you you're putting a stronger stress on your cardiovascular system and so the adaptations are greater. And part of the adaptations are you're able to bring in more oxygen, carry it to your muscles, carry it to your your you know other other tissues better. And so that's your cardiorespiratory fitness.
Uh and so and so that's that's really I would say um the bottom line here is engaging in even just once or twice a week. And I I would say the the most wellressearched protocol for that would be something called the Norwegian 4x4. And that is where you're doing a longer interval.
It's a 4minute interval and it's best done on either a stationary bike or maybe a rowing machine. And you're going as hard as you can and maintain that intensity for four minutes. And then you're gonna go down to light exercise and recover for four minutes and let your heart rate go down.
And you do that four times. So it's a four by four. And that is probably one of the most robust ways to improve cardiorespiratory fitness.
But there are other ways even doing you know one minute on one minute off. So you do one minute as hard as you can go again for that entire minute. You're not going all out, but as hard as you can and maintain that for the entire minute.
And then you rest a minute. And you do that, you know, 10 times. So it's a 20-minute workout.
>> So for the several million people that are listening right now, if you had to prescribe them all something to do and it was the minimum they had to do. Tell me what exactly the workout would look like and how frequent it would be on a weekly basis. >> I would say the minimum effective dose would be once a week.
Okay. >> And it would probably be the one minute on, one minute off. If you want like the upper end robust effects of improving cardiorespiratory fitness, you can still improve it with something like a Tabata.
>> What's a Tobata? >> Where you're doing a 20 second interval and you're going more all out because it's shorter time and then you're recovering for 10 seconds. >> So, it's a 20 second on, 10 second off.
You do that eight times. And um if you repeat that twice, so it's essentially a 10-minute workout, that's also something that can improve cardiorespiratory fitness. But I would say, and I'll tell you I'll tell you why there's the minimum, right?
So the one minute on, one minute off. But I would say the Norwegian 4x4 is the gold standard. And that's because it's not only improving cardiorespiratory fitness.
This is probably one of the most exciting pieces of evidence I've seen with respect to, you know, exercise and aging. And that is that being part of an exercise protocol was shown to reverse the structural changes that occur with age in the heart by 20 years. So what do I mean by that?
I mean, people that were 50 years old that were sedentary, so they weren't really going to the gym. They weren't engaging in any sort of physical activity, but they weren't, you know, they didn't have diseases. They didn't have type two diabetes, they didn't have cardiovascular disease.
I would argue sedentary, being sedentary is a disease, but putting that aside, they didn't have any diseases, right? And they're 50, so they're midlife. And um this was again this was done by Ben Lavine out of UT uh Southwest at in Dallas.
He took these, you know, 50-year-olds and put them on a pretty intense exercise routine for two years or a stretching routine. This was like the the control. And this type of exercise routine was progressive.
So they started out lighter and sort of worked their way up, right? Like you don't want to just start with a Norwegian 4x4 people that never never exercise. I mean that's going to be tough.
So it was a progressive sort of building up to that. But um towards the ends of about the first six months, these people were exercising about 5 to six hours a week and that included one to two sessions of the Norwegian 4x4. And it also included a lot of, you know, they're they're doing moderate to vigorous intensity cycling or running and some some strength training as well.
And they did this for two years. their hearts were looked at and so as we age our hearts shrink and they get stiffer and that plays a role in causing cardiovascular disease. I mean that's the number one killer in the United States.
It also affects cardiorespiratory fitness, right? Why does the the heart, you know, stiffen with time? Well, it has a lot to do with actually being exposed to a lot of glucose.
When you're eating a lot of refined sugar and refined carbohydrates, you're having a lot of glucose around in your system. This causes a chemical reaction called glycation. So you get these advanced glycation end products that sort of react with your collagen that's lining your heart and your mocardium and it causes it to stiffen and so now the heart can't really respond to stress well.
It's stiff and that plays a role in like heart attacks for example. So exercise is one of the best things you can do to move glucose out of your vascular system and get it to your muscles. And so that's that's one of the things that it does and helps with not causing that stiffening of the heart.
And so essentially these 50-year-olds had their their heart the structure so it was bigger and less stiff after two years of this you know exercise protocol. It essentially made their hearts look like 30 year olds. And I mentioned they were 50 year olds.
I mean, that's amazing. That's incredible that you can take someone midlife, put them on a two-year training protocol, and reverse the aging of their heart by 20 years. >> So, on this Norwegian 4x4, you've convinced me to give it a shot.
But specifically, how I how I do that. So, it's it's I do my warm up and then I do four minutes of hard exercise. I take a break and the exercise I'm doing in those four minutes can be any number of things but I just have to get up to 85 80% of my exertion levels 80% difficulty.
>> So the way it works is as they mentioned it's it's best if you're doing a cardiovascular type of exercise. So like >> the assault bike. >> You could do assault bike.
Yep. Assault bike. You can do a rowing machine.
You could do uh stationary cycling machine as well. >> Could I run? You can, but that is is it's definitely um it's I think it's better on on doing like maybe a bike or a salt bike or something.
Um but you can run like what whatever it is that you like to do and you are going as hard as you can for that four minutes and maintain within that four minutes. So it's not an allout or it's far from all out, right? But you're not really having a conversation while you're doing it.
And then the four minutes of recovery, you're if you're running, you kind of go down to walking. If you're on the rowing machine or the assault bike, you're just going very slow. You're just really going slow and you're letting your heart rate come down.
You're letting your muscles kind of recover, your cardiorespiratory fitness, you know, kind your your cardiorespiratory fitness system recover somewhat. And then after that 4-minute recovery, you go back to the four minutes of like intense again. And you're doing that four times.
It's not easy, but you know, people can start out, they don't I mean, even if you start out with not going super super hard in those four minutes where you just maybe you can have a conversation, but you're still going hard harder than you're used to pushing yourself. And I think for people that haven't really engaged in any type of high-intensity training before, that's a good idea where you kind of you got you can't just start doing it >> right out the gate. You want to kind of work your way up that.
So doing the four minutes do just try to put in as much effort as you can right during those four minutes and then you do your recovery and you repeat that four times but then work your way up as you as you do it one week two weeks you know a month later two months later and really try then to get to that point where during those four minutes you're getting you know you're pushing yourself hard where you're not really able to have that conversation.
