This is 99% invisible. I'm Roman Mars.

Hey, this is starting up. What I'm going to have you do when you get on?

I'm going to have you just stand for a few seconds, and then when I tell you to run?

That is the sound of producer Phoebe Flanagan jogging on a treadmill.

She's been observed by LaGene Lawson, one of the world's leading experts on sports bras.

Lawson uses all kinds of fancy equipment, like a 3D imaging machine,

to understand the biomechanics of breasts and how they move when women exercise.

The breast will rise up and then it has to go down again. It changes direction constantly.

The accelerations, which is either speeding up or slowing down, where the the nipple is changing direction.

It can be very high. I did a little research and I said, you know, a 30,

60 nipple can go from 0 to 60 faster than a Ferrari.

Really? Much faster.

Okay, let's see.

For the past 30 years, Lawson has worked as a researcher and consultant to champion athletic wear.

She specializes in sports bra design. Sports bras are a piece of clothing that women might

take for granted today, but they were totally revolutionary when they were first invented.

They opened up whole new realms of sports and exercise to women.

Not just because I've spent 33 years studying it, do I say this? I know from conversations

with literally thousands of women that this is a game changer for them.

Today, we're going to feature a story from our friends at the outside podcast from

Outside Magazine and PRX. They did a whole episode dedicated to the design and history of the sports

bra. We'll start back in Lawson's lab with reporter Florence Williams.

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