NEW YORK (NYTimes) - In a rental space on West 36th Street, 18 people in two lines stretched, did shoulder rotations, lunges, neck rolls and ran in place. Most wore sneakers and workout gear, along with black T-shirts with "Rogue Alliance" printed on them in white.

It looked like any other exercise class. Except for the lightsabres.

The massive, cultlike following of the Star Wars franchise (tickets went on sale for The Last Jedi, which opened Dec. 15, in early October) has entered the fitness and performance zone. Rogue Alliance, formed one year ago, focuses on martial arts, stage combat, sword fighting and sabre choreography. Its members also perform at conventions, movie premieres and Stars Wars-friendly events.

"People come because it's fun," said Mr Daniel Reiser, 41, a special education teacher and co-founder of the Alliance. "It's good physical training in terms of handling the endurance for the fight performances. Plus it brings in the whoosh of fantasy from a cultural and iconic source."

For the next hour, participants discussed and practised several different forms of sword fighting, always incorporating their lightsabres. First there was fencing. Then German longsword, followed by stage choreography. Last was Shii-Cho, one of seven sabre forms of fighting that appear in Star Wars. The click of light sticks reverberated throughout the room.

"The wall side is attacking, mirror side is on the defence," said Mr Brandon Hughes, 36, a legal assistant, who was the instructor that night. "Let's practice doing the shape of an A with the sabres. Hip, hip, head. Hip, hip head." The tone remained lighthearted but serious as tips and tricks were shared. Veterans, using Star Wars lingo, helped newbies understand specific moves. Lightsabres - which in this universe are usually polycarbonate tubes illuminated from a lighting device in the handle - beamed yellow, red, pink, light blue and green. Some were basic, others more ornate. One member created his handle using parts from a vacuum and from the Custom Sabre Shop, an online tutorial and sabre blade supplier.

"I love being here; Rogue Alliance is the outlet I needed for creativity, fun and athleticism," said Ms Melissa Koval, 32, a legal assistant. "It allows me to give back because I'm part of the charity component," she said, alluding to the fact that many of the events she attends with the Alliance raise money for specific causes. "So it lets me be altruistic, creative and a sword nut."

She met her partner, Mr Russ Briggeman, 33, also a member, doing sabre combat six years ago. "I accidentally broke his finger playing with these," she said, nodding to the two short bladed sabres in her grip. "We have about 15 more on our walls at home."

The group is surprisingly busy. Recently, members performed at Wintercon, one of the largest science fiction conventions in New York. "It was a narrative show with a pirate theme using lightsabres, and we raised money for the Starlight Children's Foundation," Ms Koval said. The group also made an appearance earlier this month at Ace Comic Con at Nassau Coliseum in Long Island, and at the Alamo Drafthouse on Dec. 15 to celebrate the premiere of The Last Jedi.

"This is very much a support group where we all study together," said Mr Craig Page, 31, a freelance writer. "When I first saw this group I thought, This is the greatest thing, it mixes all my interests," he said. "When we put on these shows, for a second we make the audience feel this is real - that Star Wars is real - that Jedi and Sith can fight each other."

An hour into the class, two groups had been formed. One discussed the logistics, like costumes and timing, for an upcoming performance. Newer members worked on their Shii-Cho skills. This was followed by simulated sabre fights breaking off in different corners of the space, each looking like a mini laser show.

Next came "fight showoffs" between two people, while the rest of the class watched. When a duo would finish, spectators would pound their lightsabres on the floor instead of clapping.

The class concluded with participants coming together in a tight circle. They made the not-very-difficult decision to cancel class on Dec 22 so that everyone could see a screening of The Last Jedi and have dinner together afterwards.

Then it was lights out.

In the dark they joined their illuminated lightsabre tips in the middle of the circle and shouted some affirmations, ending with an impassioned, "Rogue Alliance!"