Erin Weaver and Charlie Brady in "Xanadu."

Everyone knows whether they’re right- or left-handed. But right- or left-footed? Maybe not so obvious — until you lace on a pair of skates. Erin Weaver, starring as quirky Muse Kira in Signature Theatre’s production of the musical extravaganza “Xanadu,” is right-footed, which means nothing to most people, but a great deal to a leading lady on wheels.

“Point your toe,” instructed skating choreographer Gregory Vander Ploeg as Weaver practiced her routine to the song “Magic” at a recent rehearsal. Over and over again, Weaver did a left toe-stop turn (a sort of balletic twirl) — and stalled (blame the right-footedness).

“We’ll work on it,” said Vander Ploeg, who spent five years performing in the train-themed roller-skating musical “Starlight Express” in Las Vegas. “Then, we’ll add glitter and lasers and fairy dust.” And sets and lights and gloriously ’80s costumes. And an orchestra. Nobody ever said musicals were uncomplicated.

“I joke with my husband that sometimes I wish I could be working on Shakespeare. … I’ve never worked this hard on anything in my entire life,” says Weaver, who spends nearly the whole production singing, dancing and acting — on skates. (She’s not alone — eventually the entire cast joins in on the wheeled choreography.) Weaver plays the role originally held by Olivia Newton-John in the 1980 film of the same name, about a Greek goddess who inspires a Los Angeles artist to achieve disco greatness. Who knows whether Newton-John had to endure these sorts of rehearsals.

Neither Weaver nor fellow lead Charlie Brady were skilled skaters when they were cast in the show. Brady Rollerbladed in high school, and Weaver “mostly just skated forward and flirted with boys.”

“I think there was a lot of blind faith going into this,” says Brady. Not to mention a lot of sweat. Weaver and Vander Ploeg practiced together at a rink in Laurel, Md., where they went from Weaver’s first tentative attempts to skate backward (“It was like ‘Bambi,’” she says) to her current turns, arabesques and toe-stops on a dime. Two days before rehearsals, the entire cast attended an intensive skate camp where they progressed from timidity to falling — but falling fiercely.

And even though the skating adds an extra layer of difficulty to the already demanding experience of being in a musical, in a way it helps everyone focus. “In skating,” Weaver says, “you have to be in the moment.”

Despite the ongoing jokes about adding a lip to the stage to keep actors from pitching into the audience — or a plexiglass wall — Vander Ploeg isn’t worried about his fledgling skating corps. “By being on your skates every day, you become really comfortable,” he says. “Eventually you have to stop thinking about your skates and just do the show.”

Signature Theatre, 4200 Campbell Ave., Arlington; through July 1, $62-$86; 703-820-9771.

Ready to Get Rolling?

Though you won’t have a choreographer to hold your hand, you can get rolling at one of these local spots. If you want to find friends to skate with, check out Meetup groups like Washington Area Roadskaters, which brings together in-line skaters for skate sessions all over D.C.

The White HouseYou can’t expect the Secret Service to catch you when you fall, but the trafficless stretch of Pennsylvania Avenue right in front of Barack Obama’s house is a great place to practice your toe-stop turns. Try to avoid running into any tourists on Segways – they’re bigger than you are. (McPherson Square)

Temple Hills Skating Palace: Even though it’s a trek from the District to most indoor roller-skating venues, we prefer rinks to outdoor skating: fewer cars, more “Now That’s What I Call Music”-style tunes. Temple Hills Skating Palace has adult nights, teen nights and themed-music nights where you can roll to gospel or R&B.

Temple Hills Skating Palace, 3132 Branch Ave., Temple Hills, Md.; 301-505-6490. (Naylor Road)

Laurel Roller Skating Center: If you’d like to skate outside or on your own but want some time with a professional first, you can take skating classes here for $20 per month. The center also hosts general skating, disco evenings and rave-y lights-out skating where the price of admission covers a glow stick.

Laurel Roller Skating Center, 9890 Brewers Court, Laurel, Md.; 301-725-8070.