New studio Brrrn offers cool-temperature workouts in Flatiron

This is literally the coolest workout around.

At Brrrn, which officially opened Tuesday in Flatiron, fitness classes are held in a room that’s chilled to temperatures as low as 45 degrees.

The studio concept is based on what’s known as mild cold stress, according to co-owner Johnny Adamic. Research has shown that people may burn more calories in temperatures between 40 and 64 degrees as your body works to maintain its core temperature.

“Cold is really good for you, but we’re hard-wired to not like cold,” said Adamic, a former public health official for Mayor Michael Bloomberg’s Obesity Task Force, personal trainer and fitness critic for The Daily Beast. “We live in a thermal cocoon — we’re always in 72 degrees, but that’s not the human experience.”

The studio currently offers three 45-minute classes, held in three different temperatures: a yoga-based mobility and strength workout at 60 degrees; a low-impact core and cardio workout done on a 5-foot slide board at 55 degrees; and a high-impact battle rope- and HIIT-based workout at 45 degrees.

Gloves and headwear are recommended. But despite the cool temperatures, the workouts are designed to get you sweating, especially the battle rope class.

The modalities are also offered at various times throughout the week so that you can switch it up, said co-owner Jimmy T. Martin, a performer (and former amNewYork hawker) turned personal trainer.

Martin was inspired to open the unique studio after learning about the benefits of mild cold stress and exercise.

“The [fitness] space is very overly populated,” Martin said. “We’re thinking outside the box.”

The studio is three years in the making, with trial workouts held in Sixpoint Brewery’s beer fridge in Red Hook and at an ice factory in Swoyersville, Pennsylvania.

The co-founders were further encouraged by research from Scott Carney, author of “What Doesn’t Kill Us: How Freezing Water, Extreme Altitude and Environmental Conditioning Will Renew Our Lost Evolutionary Strength.”

That book is on hand at the studio, should visitors be seeking some pre- or post-class reading material. After their workout, clients can also cool off with a preferably cold shower, Adamic notes, or hit the eight-person infrared sauna — the latest amenity in studios and spas across the city — for 40 minutes.

Classes and sauna sessions are $34. The studio is located at 107 W. 20th St. For more information, visit thebrrrn.com.