This Is What It Girls Wear to L.A. and NYC's Cult Fitness Classes

It's no secret that celebs inspire how we get dressed, where we shop, and what we shop for. Whether we're copying their most iconic outfits (ahem, Jennifer Aniston circa 1990) or taking our best guesses at what we'd find in their Zara shopping carts, there's no end to the inspiration. Today, we're diving into one more area of our closets where It girls are wielding some powerful influence: workout outfits. However, we're not talking about any old outfits they throw on to head to the gym.

Instead, we're highlighting five celebrity workout classes in both NYC and L.A. that have earned cult followings from actresses, models, and fashion insiders alike. These are the studios where you'll spot the coolest new legging trends and activewear brands to know while you break a sweat. So what exactly do celebs wear to each buzzy fitness studio? Keep reading to discover why each workout is so popular among the A-list crowd and the outfit combos you can expect to spot them in.

To Body by Simone: Comfortable Layers + Supportive Sneakers

Body by Simone has earned itself somewhat of a cult following in the celeb world, counting loyal fans like Rosie Huntington-Whiteley, Jennifer Garner, and Chrissy Teigen, among others, who come to the studio's high-intensity dance-cardio classes on the reg. The studio's owner, Simone De La Rue, says that wearing supportive sneakers is a must since the class involves lots of jumping around and, of course, dancing. As for what else her clients put on for class, matching legging-and–sports bra sets layered up with a looser-fitting top is the outfit combo of choice.

To Alo Yoga: High-Waisted Leggings + Sports Bras

You might already know Alo for its amazingly soft leggings (Hailey Bieber is a huge fan, for instance), but some of its stores also double as yoga studios. Celebs like Claire Danes and Jamie Chung flock to the Beverly Hills and SoHo locations for vinyasa flow sessions, typically clad in one of the brand's matching legging-and–sports bra sets. Its extra-long Goddess leggings are a favorite, according to the brand.

To Rumble Boxing: Sports Bra + Shorts or Leggings + Sneakers

Justin Bieber, Kendall Jenner, Hailey Bieber, Jason Derulo, David Beckham… We could go on, but we think you get the gist. Celebs show up in droves to Rumble's high-energy, pop music–filled boxing class on both coasts. The class is a mix of heartbeat-raising boxing sessions, weight training, and some good old cardio, so naturally, the studio insists that good sneakers are a must.

"I recommend choosing a pair that’s designed for training, stabilizing, and allowing ballistic movements, like jumping and bouncing," Kendall Wood, a trainer from the studio, told me. "That said, I would not recommend wearing super-baggy clothing to a Rumble class. Anything that can get caught on equipment or inhibit movement should be avoided!"

To LEKFIT: Bike Shorts + Bra Top + Sneakers

LEKFIT is admittedly unlike most other workout classes. According to founder and celeb trainer Lauren Kleban, the class is "designed to work the full body using intervals of low-impact, high-intensity, fat-burning cardio with muscle-sculpting techniques created to strengthen and tone." Since devoted fans like Busy Philipps, Emmy Rossum, and Jen Atkin leave Kleban's class dripping in sweat, they usually show up in bike-short or legging sets and, of course, sneakers. Kleben told us that all the LEKFIT trainers are loyal to Adidas Ultraboost sneakers.

To ModelFit: Leggings + Sports Bra + Light Sweatshirt

As the name suggests, ModelFit is popular among the model and celeb crowds. It's based off specific sequences that target and tone the smaller, hard-to-reach muscles, and depending on the instructor, they'll utilize different pieces of equipment such as resistance bands, ankle weights, Pilates ring, etc. And since it's all about toning (in other words, you won't necessarily come out dripping in sweat), throwing on a light layer like a sweatshirt or jacket over your typical legging–sports bra outfit is a good idea.

Next, see how I re-created Jennifer Aniston's most iconic 1990s outfits.