Young people are building fitness portfolios. Solidcore wants a bigger piece of them.

Solidcore is expanding its brand with a new class focused on heavier weight training. Courtesy of Solidcore Boutique fitness brand Solidcore is beefing up with a new strength-focused class in infrared heat. It's a big bet on resistance training as the future of fitness, with emphasis on longevity. The balancing act is reaching new audiences without diluting what hooked loyal fans in the first place. Solidcore is expanding beyond its signature workout for the first time in its nearly 13-year history. When Solidcore launched over a decade ago, the brand found success with an intense 50-minute workout on Pilates-inspired resistance machines , known as reformers. This winter, it will debut Ascend, a high-intensity, heated, floor-based strength training class, according to details shared exclusively with Business Insider. The class will launch at Solidcore's upcoming Manhattan West studio, before rolling out to other locations.