A neon crowd of girls stand in a black-lit room, yelling to each other over the pounding bass of the dance music. It could almost be a typical scene from a Friday girls’ night Uptown. There will be dancing, maybe even a punch or two thrown. But it’s 8 p.m. on Thursday night, and they’re not at Brick Street, New Bar or anywhere else Uptown.

The black light hits neon leggings, t-shirts and tennis shoes that occupy the space where workout equipment usually sits. They’re in a fitness room at the Rec.

Two girls with glow-stick glasses and flashing rings break away from the group of over 20 girls. The music quiets and the neon mob falls silent.

“Hey guys! Thanks for coming to Light Up the Night. Who’s excited?” yells the dark-haired girl in glowing, blue glasses.

The girls respond with a half-hearted, “Woo.”

“No, no, no,” the girl in the front says. “Not good at all, let’s try that again. I said ‘Who’s excited?’”

The woo drowns out all other noise this time.

“Better! Okay, I’m Meg and I’ll be teaching kickboxing tonight. This is Morgan,” she points to the blond girl in matching glasses, “And she’ll be leading Zumba. Here we go.”

The music roars up again, and Morgan takes her place at the front of the pack.

Everyone stares at their bright reflections in the mirror while they wait for Morgan to start. She leads them through a warm up, then bursts into choreographed Zumba moves that she probably knows in her sleep. The rest of the girls don’t know them quite as well, but they mouth the lyrics to the songs they know, throw their own spin on Morgan’s moves and snap pictures on their short water breaks.

The girls churn through mashups of Top 40 hits and latin jams — bass pounding through it all. Every once in awhile, Meg tries to lead another “woo,” but as the hour goes on, the responses get quieter and quieter.

The glow-stick bracelets, rings, neon shirts, headbands and, in one case, bunny ears, illuminate the girls’ movements. Meg and Morgan throw their glasses to the side whenever the difficulty level picks up, and almost everyone’s dance moves are getting more sluggish. But they smile through it all.

Then, about 45 minutes in, Morgan leads them back through some more basic exercises and thanks them, turning the class over to Meg.

“Okay, guys, now we start the kickboxing portion of the class! Here we go on four, three, two.”

Meg yells out directions while throwing hooks, jabs, crosses and upper cuts toward her reflection in the mirror. Before they’re through with the first exercise, the girls look tired. Even Morgan is panting and gulping water.

A few girls start to trickle out, clearly exhausted. Meg keeps pushing the glow-in-the-dark girls behind her, yelling words of encouragement as the neon lights start to reflect off of the sweat dripping down everyone’s faces.

She leads them through kicks, squats, punches and cardio blasts. When she initiates a woo, no one but Morgan answers. But there are still smiles on their faces as they’re pushed through a brutal workout they know will have its rewards. The kickboxing portion only lasts for about 25 minutes before Meg leads them through a cool down.

“Thank you guys so much for coming, she says. “If you liked this, we have classes through the semester so make sure to check us out online!” Her audience looks up at her from where they stand, hands on hips, heads hanging down, trying to catch their breath.

“You guys were amazing, and be proud of yourselves. You’re better for doing this,” Meg says. “Thanks again!”

With that, the class is over, and a luminescent stream of girls flows from the room.

A girl takes a swig of her water and looks at her friend: “Oh my God, I’m so dead.”

Her friend nods in agreement before saying, out of breath, “Yeah, I think we should do it again.”