NEW YORK • At first glance, the streaming fitness class looks like any other: blue yoga mats against a neutral background, with ambient music and candles to set the mood. Two athleisure-clad instructors, flanked by hand weights, introduce themselves. The giveaway is the flash of a wooden crucifix. "Surrender all and prepare yourself to go on this journey with us through the stations of the cross with Jesus," one of the instructors says, her hands in prayer position. Many such classes are available through SoulCore, a fitness platform where stretches correspond to the Apostles' Creed, push-ups are completed to the Lord's Prayer and challenging positions warrant a Hail Mary. Since 2013, the company's mission, carried out by some 150 instructors in 30 American states, has been to further animate Catholic teachings, including Christ's suffering. "Coming up into a plank position, picture Jesus being condemned," Deanne Miller, 54 and a founder of SoulCore, instructs h..