Dr. Kevin Tracey

And the proof of this came just a couple of years ago from a study in New Zealand.

where the researchers put sheep on an elevated treadmill and had them run, which I just think is a farsight cartoon.

I think that is a riot.

If Gary Larson hasn't done one and he's listening, he should draw that, right?

What the question was, when the sheep are exercising, what's going on with their autonomic nervous system?

And what the results showed is that, as you'd expect, when they're jogging along...

the sympathetic fibers, the adrenergic fibers to the heart increased their activity, heart rate goes up, blood pressure goes up.

Fine, check the box.

When they looked at the vagus nerve and measured the activity, it also went up.

And when they

when they blocked that activity, either blocking the nerve with drugs or cutting the nerve, what happened was the cardiovascular performance of the sheep declined.

Cardiac output went down and coronary artery perfusion went down.

That means, which is what you would expect if you were designing the system,

that the fight or flight and the rest and digest are acting in synergy to optimize cardiac output and cardiac function, which is exactly how you would design it if you were the great designer.

That's how you would design it.

And that's how insulin and glucagon work.

That's how clotting and fibroanalysis work.

Everything, the opposing things work together to get a fine balance.

And so that's actually a really important point and leads to where you started all this is with POTS.

In COVID, what we saw convincing evidence that in some, it started with autopsy studies, actually, of people who died from COVID in Spain, that their vagus nerves were damaged in a number of those people.