Welcome back to the Barbaugh Medicine Direct Line, our monthly Ask Us Anything for our Barbell Medicine Plus subscribers. I'm Dr. Jordan Flagenbaum. We've got a stacked set of questions today and a lot of it comes down to one recurring theme. The advice that was supposed to protect you might be doing the opposite. And to help me unpack all of this, we have the second most hands on, I'm Dr. North America. Dr. Austin Baraki, what's going on, dude? Hey, doing all right. I'm looking forward to

the breadth of topics that you've pulled together or that our audiences pulled together. I just

wrapped up some training this morning and I'm comfortable, ready to go. All right, let's get into

the first question. This one's on V-O-2 Max versus cardiorethreatpiratory fitness for longevity.

The question is, is V-O-2 Max the metric we should or could reference for cardiorespiratory fitness for longevity. The question is, is V-O-2 Max the metric we should

or could reference for cardiorespiratory fitness when it comes to longevity? Dr. Eric Topol

points out the data comes mostly from measures of cardiorespiratory fitness, not actual measures

of VOTU-Mex. How does this square with Dr. Peter Atia's recommendations for VO2 Max?

So to start, yeah, these aren't the same things. VO2 Max and Cardi Restopority Fitness are distinctly different. And most of the longevity studies that Dr. Atia has cited, they don't actually ever measure VO2 Max. We can fully concede that. VO2 Max, for those who are listening to Home and may be unfamiliar with what it actually is, it's a measurement of your maximum oxygen uptake. It usually requires a maximal effort test with a metabolic cart to get a real number. Cardiorespiratory fitness, on the other hand, is more

broad than that. In most large studies, it's an estimated treadmill test, estimated exercise test

sort of thing.

You take it to tolerance where people either have signs, if it's like a cardiac rehab sort of situation or just otherwise they feel some breathlessness, they can't continue.

And so you get a measurement of metabolic equivalence at peak effort.

You can also get a submaximal test.

There's also questionnaires.

There's a bunch

of different ways to test it. But most of the time in the research, it's an exercise tolerance test

sort of thing. So Atia, despite this, gives specific VO2 max percentile targets by age and sex

in his book, despite the underlying studies, not actually measuring that. So he says, despite all this, that VOTU Max is the single most powerful marker for longevity.

He's been saying it on his podcast.

It's all over his book, Outlive.

And honestly, he's probably right directionally.

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