- Out, hold, holding out, and rotate.

- The world is changing, but women still, by and large, there's a huge expectation, right?

That we're calm and we're cool and we're collected and we're kind and we're nurturing and we're supportive.

We have just as much frustration and energy that needs to go somewhere.

When you don't have that athletic outlet to get that out and to have it somewhere, it gets kind of pent up.

And so I think that's where a lot of the draw comes from for us, for the most part, it's just that freedom to be powerful.

And everybody is rooting for you to be powerful.

(whistle blows) - [Stefanie] Flat track, roller derby, a mix of athleticism, theater and aggression.

It's full contact and the skaters love it.

- [Pepper] It's not done in a mean or violent spirit, it's done in a competitive spirit.

It's the expectation all on wheels.

The word is getting out about some of these things and about the community of roller derby and the supportiveness and the empowerment and the acceptance.

And it's okay to be pretty and powerful.

It's okay to be any body size or body shape, or any of that that you have because it all works and it all fits in this space.

- [Stefanie] Born on 1920's bank tracks, roller derby sped from punishing pileups to spirited scripted TV in the 1980s, then skidded toward oblivion.

A Texas crew yanked it back in the early two thousands, ditching theatrics, writing flat track rules and handing control to the skaters who still drive the sport today.

- Texas roller girls actually said, "This is an athletic sport, we can do something with this."

And they got together with some other folks in the WFTDA, Women's Flat Track Roller Derby Association, kind of was born.

And that was 2001.

And by 2010, roller derby was in 15 countries.

It just, it took off like wildfire.

And in the last few years here in the states, it really, really has grown.

- [Stefanie] Pepper went roller derby in the Mayhem, because her New Year's resolution was simple.

Try something new.

One night on skates was all it took.

She rolled out battered and bruised, but with a brand new community at her back.

- Roller derby community is just so encouraging.

I mean, I would get out there and I'd be falling flat on my face and people would still be saying, "Get up, Pepper.

You can do it.

Keep going, get back up.

You've got this, you've got this."

- [Stefanie] Players must master certain skills and learn proper techniques like falling to gain a roster spot.

Once they get that spot, they're given a derby name, an alter ego for the track.

Pepper becomes Cayenne Calamity.

- You create a persona for the track, right?

You let part of you that doesn't get to see the light of day kind of come out.

I'm a college instructor and a high school teacher.

We have a physical therapist on our team.

We have someone who has a home daycare, we have a tattoo artist, nurses.

There's a lot of walks of life.

- Roller derby can definitely look like a ride on wheels.

But the beauty is that you don't need to know every rule just to enjoy about.

On Saturday night, the hardwood at Pins Bar and Grill crackled with energy as the Central Michigan Mayhem clashed with the Synergetic Sweethearts in a duel that had the crowd on it's feet from the first whistle to the final jam.

Momentum swung back and forth, penalties mounted and the Mayhem even lost players to ejection.

But the Mayhem held off a late push and squeaked out a 132 to 124 victory.

The real draw is the energy in the room, seeing a community of women giving it their all and leaving it all out on the track.

(group cheering) - And when I get on the track, I can hit people and I can knock 'em down.

I'm allowed to be strong and confident.

It's a place to find that confidence that you don't give yourself permission to have.

And everybody knows you're gonna get hit and everybody's cool with getting hit.

The harder you hit, the better.

And people high five you and say, "Man, that was a really good hit."

Even if it was them that you just knocked on the floor.

Some people walk away saying, "I don't know how you guys do that.

That is crazy.

Good for you."

And some people walk away and say, "I will be at your next practice, 'cause I think I wanna try that."

(group cheering)