Joyful Heart in the News

Ms. Hilty collaborated with her friend and trainer Dasha Libin on the event, which raised money for the Joyful Heart Foundation, an organization founded by Mariska Hargitay that helps victims of sexual assault, domestic violence and other abuse. And Ms. Libin is the creator of a workout called Kettlebell Kickboxing, which she usually teaches out of her studio on lower Broadway.

"I've been doing martial arts my whole life," said Ms. Libin, who complemented her shrieking pink athletic jacket with a shrieking yellow athletic top and—"because I wear fitness clothes all day"—a white Alexander McQueen bangle with skulls on it. "And my grandfather taught kettlebells to the Soviet army. I use them because of the unique way they train your body."

Ms. Libin said she has been teaching her unusual mashup of two fitness crazes "in public since 2010," but only got to know Ms. Hilty after watching her on "Smash."

"I stalked Megan Hilty," explained Ms. Libin, who, considering her knowledge of martial arts and how to use a kettlebell, plus her proclivity for Alexander McQueen skull bangles, might not be the easiest person to evade. "You can see her work ethic on the show and on Broadway. I appreciate that. I love it when people take the long road."

"I've tried everything. Every fad," said Ms. Hilty. "I get bored very easily. And with my schedule, even the gym is really hard to get to. But we have so much fun in our workouts. We thought, maybe we should do something that helps raise awareness."

Ms. Libin and Ms. Hilty involved some of their friends and acolytes. Tiffany Rinehart, the comedian Kathy Griffin's longtime assistant, was there; she started doing Ms. Libin's videos after a friend told her about Kettlebell Kickboxing.

Joanne Nosuchinsky, Miss New York 2013, who normally works out four times a week, did Kettlebell Kickboxing wearing her tiara and sash. "It was simple but intense," she said. "I normally separate my cardio from my weights routine. But I'm looking to be lean and ready."

Over the weekend, Megan Hilty, a star of the television series "Smash," which returns to NBC for its second season this week, hosted what promoters were calling the first ever "fitness gala."

This was the kind of event where a large number of women left their Louboutins and their Louis Vuitton at home, and instead showed up to the Midtown venue in their best Lululemon, and other workout clothes. To walk into Studio 450, a penthouse space in the West 30s, was to see ladies in various shades of pink, but mostly of the hot and fluorescent varieties.

And the accessory of the morning was a kettlebell.

As for whether she typically wears her sash and tiara to work out, "Always," she said. "They provide some additional resistance. That's a joke by the way."

Ryan Serhant of Bravo's "Million Dollar Listing," came "to serve Champagne to all of these sweaty girls," he said. He was dressed in a suit, and said he knew Ms. Libin and Ms. Hilty through various real-estate transactions.

Why wasn't he doing the workout? "I could never do this," he explained, as the ladies finally put their kettlebells down. "This looks really hard."

Several VIPs, including Ms. Hilty, the musical-theater star Eden Espinosa and Ms. Libin, retired to a loft space upstairs where they were plied with trays of ice cubes and healthy treats, like miniature sun-dried- tomato and basil frittatas and frozen yogurt pops made from Chobani yogurt and fruit.

Ms. Hilty, who is about to release her first solo album, was in a corner cooling off, waiting for one of those Chobani pops to thaw. Ms. Libin, she explained, "always says, 'I'm going to make it really easy today.' But then five minutes in, I'm drenched."

Besides Kettlebell Kickboxing, Ms. Libin has also been teaching Ms. Hilty Muay Thai, a combat martial art.

"It's been empowering and fun," Ms. Hilty said. "It's given me an awesome confidence."

"Now she kicks the level of a pro fighter," added Ms. Libin.

"Yeah, if there was a musical theater Broadway brawl, I could take them all," said Ms. Hilty.