Today, many Americans are making a new year's resolution to exercise more.

It's well known that regular exercise is good for your health, but a new scientific

consortium is revealing fresh insights into just how profound the benefits are for the human

body.

William Brigham spoke recently with someone who's helping lead this research, UN Ashley.

He's a professor of cardiovascular medicine and genetics at Stanford University

and the newly named chair of its Department of Medicine.

And he calls exercise the single most potent medical intervention ever known.

You and Ashley is so good to have you on the news hour.

You are undertaking this massive,

multidisciplinary study to understand how exercise changes our body in some fundamental way.

But as I mentioned, don't we already know a lot of this? I mean, what is the importance of doing this much deeper dive that you're doing? Well, we've known for maybe 70 years

that exercise was among one of the most potent medical interventions known. We knew from studies in the

1950s comparing London bus drivers and London bus conductors that lived in the same environment,

but the bus drivers were sitting, the conductors were standing, and the heart disease

rate among the drivers was twice that of the conductors. So yes, we've known for 70 years that

exercise is really, really good for you. But we have not, through that entire time, really understood

how it works. So the new study was to bring together 17, 18 different groups from across the United

States to really study,

to build a molecular map of exercise, to try and work out how come this intervention that's

so available to all of us is the most powerful intervention known?

How does it actually work?

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