There are many kinds of jump ropes. Some are made of soft rope, but are harder to control. Plastic ones sting a bit when they hit your ankles, but are gentle enough to keep novices generally injury-free. But then there are those with thick, plastic beads surrounding the rope—ideal for tricks, since the weight makes them easier to control. But if your timing gets off and you jump a second too late, the massive plastic beads strike, leaving red welts across arms, legs, and—in one recent cringe-inducing moment—Stacy Brewer’s face.

“The redness goes away,” assures Brewer, who goes by the handle “Stack.”

Brewer is part of the five-member jump-rope team On the Double. At face value, the group—founded in 2003 by Amy-Ellen Flatchestedmama Trefsger (yes, she had her name legally changed) and Andrea Gardner—is a bunch of hipsters having a get-in-touch-with-your-youth moment. Two sport hair dyed black, another thick, bleached layers; there are tattoos and vintage socks for all. (Trefsger will also stage a solo performance-art piece for Artopia: a Lucy-style advice booth called “Inquiries for an Artist Who Doesn’t Draw or Paint.”)

But the double-dutch team doesn’t just exist for the sake of irony. Thanks to two-hour practices twice a week, they’re serious jumpers. During what looks to be an exhausting two-and-a-half-minute routine requiring near-constant hops, they call out tricks, including cartwheeling in and out of the whirling ropes, hitting the ground push-up style, and switching out twirlers without interruption.

None of the women on the team—all in their 30s—actually double-dutched as a kid, Trefsger explains. Jump rope just wasn’t a thing in rural Pennsylvania, where she grew up, she says. “I’d never even seen it.”

Gardner had been on an adult double-dutch team in San Francisco and got Trefsger into it. At first it was just kind of a play thing—they got some friends together and started messing around with the ropes. But as they got better, they brought in friends with more expertise to coach, and culled YouTube for ideas.

Since starting the group, Gardner has actually made it her vocation: She is now a full-time instructor through her company Northwest Double Dutch, which hosts one-off classes and longer camps for both kids and adults.

It was through one of those classes that Brewer, Stacey “Ace” Merrick, and Hollis “Kung Fu” Rendleman got to know Trefsger and Gardner and joined On the Double. Trefsger says members tend to rotate in and out pretty quickly—in addition to the small, temporary welts that are the hazard of learning to double-dutch, past members have been felled by more serious ankle injuries.

Still, the dangers haven’t dissuaded the current team, whom I recently caught polishing their act in matching black athletic skirts in a Capitol Hill elementary-school gymnasium.

Trefsger watches Rendleman struggle with switching out twirlers. “You’ve got a whip-it arm on that one,” she finally diagnoses—a tendency to jerk the rope too quickly just before starting a trick. With less than two weeks to go before Artopia, there are a couple of hiccups in the routine to iron out.

It’s easy to get a little snarky about hipsters doing things like playing dodgeball or riding around on fixies. But double dutch makes no allowances for casually dipping a vintage-Saucony-clad toe into memories of youth, it takes a real commitment. On the Double jumps for keeps—and have the welts to prove it.