Dr. Benjamin Levine: If you're going to ask me, what does high-intensity training mean? That's a whole 'nother discussion.

Dr. Benjamin Levine: I know you met with my friend Marty Gibala and had a discussion with him a few months ago. When I think about aerobic power, I like to think about Jan Hoff's 4 x 4, which is the old Norwegian ski team workout. Four minutes at 95 percent to max, followed by three minutes of recovery repeated four times. Even if you don't have a heart rate monitor on, it's basically as hard as you can go for four minutes. And at the end of that four minutes, you need to be ready to stop. And then at the end of the three minutes of recovery, you need to be ready to go again. And that's how you judge that intensity, completely independent of heart rate.

Dr. Benjamin Levine: And I think that if I compare a 30-minute moderate intensity session versus a 30-minute 4 x 4, clearly the 4 x 4 will have a greater benefit on improving aerobic power session per session. That being said, over time, I think there are great benefits to doing more moderate-intensity exercise. Also, it's lower risk, it's easier to do. It's emotionally easier for many people. Others love doing short-duration burst activity. They say, oh, my God, I can get… I mean, I can get the same benefit by only exercising for four minutes as opposed to 40 minutes. I'll do it. So it's very individual. And at the end of the day, certainly when you look at a competitive athlete, no athlete does just one thing.

Dr. Benjamin Levine: That's why a lot of the studies… That's why a lot of the studies in this field are a little bit artificial because they say, I'm going to do only moderate intensity training. There's a whole new burst of enthusiasm for zone two training. I mean, gosh, I've had about ten interviews about what is zone two training for your audience? Typically that means exercising hard enough that you get a little sweat on your brow, you can still talk, but you're a little short of breath. And I like to tell people, you can talk, but you can't sing. That's a good indicator of that higher level of zone two training. So the ideal strategy then is to incorporate all kinds of training. That's what the human body is best at adapting to.

Dr. Benjamin Levine: It doesn't really adapt very well to doing the same thing over and over and over again. You will not get fitter if you do that. And in fact, in our two-year training study, if you read below the lines a little bit, we markedly upscaled people. These were completely sedentary and we worked them very hard for a year, including multiple high-intensity sessions, prolonged sessions. But then we said, all right, I want you to sustain that for a year. So we dropped them to only one interval session a week and one long session a week. And we didn't increase the dose. We didn't increase the frequency or duration or intensity over that last year. And you know what? They didn't get any fitter and their hearts didn't get any bigger. The only thing that got bigger was the atria.

Dr. Benjamin Levine: And we can chat about that when we get to talking about toxicity of exercise training. So the human, to come back to our point, the human body doesn't adapt very well to doing the same thing over and over again. And so my prescription for life, if you will, is one that mixes things up. So I suggest to people that you spend, do at least one day of a long session that lasts at least an hour, and it should be fun. I don't care what it is. It could be, you know, going square dancing. It could be a long walk with your spouse or a long bike ride. It could be some other class that you take, but it needs to last over an hour and it needs to be fun. Second thing you need to do is do one high-intensity session a week. I like the 4 x 4. I think it's very effective.

Dr. Benjamin Levine: There's great data about it from the Norwegians, but I don't care if you did 2 by 6 or if you're a Marty Gibala fan, if you did 30 seconds times eight, it doesn't really matter. Just do one thing at high intensity, and then do two or three sessions of that moderate intensity, at least 30 minutes getting the talk test, and then supplement that with one or two days of strength training. And what I mean by strength training, it doesn't mean you have to go to the gym and pump iron. It could be Pilates, it could be strength yoga, anything that requires training of strength and skeletal muscle. And if you do that over your whole life, I think that's the best strategy for preserving cardiovascular health. Now, if you tell me you want to run an Ironman, you got to train different than that, okay?

Dr. Benjamin Levine: And that's a really important thing for your audience to understand. Training for health versus training for performance, right? Every coach knows how to train for performance. And so if that's your objective, if your goal is to have a competitive performance objective, then you have to train differently. If you tell me your goal is, I just want to preserve my health and stay fit and have a good life, then you don't need to train 30 hours a week. But if you want to compete in Kona, you need to train 20 to 30 hours a week or you're not going to be successful. So I think you've got to just clearly identify what your goal of your fitness is and your goal of your overall health, and that's what will guide your training program over your life. Let me just add one more thing. I can see the questions circling around in your head. I forgot what I was going to say. We'll come back to it later.

Dr. Rhonda Patrick: So definitely a lot of questions, and I'm trying to figure out where to go first. So I think the cardiorespiratory fitness and the VO2 max, and lots of questions with that, starting with you talking about what your goal is. Right. So do you want to be a master's athlete? Do you want to train for health and longevity? I loved the way you explained the cardiorespiratory fitness and function, how it keeps going down with age and how you kind of want to stay above this level. And if you start way up here, you know, it's easier to kind of go down. It's going back to that same analogy, like contributing to your retirement fund. Dr. Brad Schoenfeld talked about this on the podcast with muscle mass, and it applies to so many different areas.

Dr. Rhonda Patrick: And I think cardiorespiratory fitness is another one. Right. If you're starting way up here, then the decrease with age, you know, it's not going to be as big of a deal functionally. So why do you think cardiorespiratory fitness does correlate with longevity? Is this relationship with reduced… So the higher the VO2 max, which is a marker of cardiorespiratory fitness, the lower the mortality risk.

Dr. Benjamin Levine: So I'm going to remember your question. I remember what I wanted to say, so let me go back to that. Okay. So the one thing I want to say is that exercise needs to be part of your personal hygiene. It can't be something that you just add on at the end of the day when you're tired and you don't really want to do it. It has to be part of your life, like brushing your teeth, taking a shower, changing your underwear, having breakfast. These are things you do to stay healthy. And exercise is one of those. And the mindset of people who sustain exercise over a lifetime and who are able to do this over and over again and who are able to stay fit and healthy is that it's part of their lives. It's not something they just add on.

Dr. Rhonda Patrick: Right. So you brush your teeth twice a day because you don't want cavities. Well, you exercise because you don't want cardiovascular disease. Right. I mean, that's, there's other reasons you exercise, too. Dementia. But, yeah, I love that "part of your hygiene" where it's not just, ‘Oh, it is this thing I have time for.’ No, you do it. It's just like you brush your teeth.