Self-powered treadmills, sans electricity, play a starring role at the new Superstar Gym in Tribeca, where European-inspired group fitness classes are taking off. At Right Fit NY in the West Village, owner Romeo Gousse added a Woodway Curved treadmill to his facility after an NFL player-client suggested it. Even Barry’s Bootcamp occasionally gets in on the unplugged action, by occasionally having class go-ers switch their treadmills into “dynamic mode” so your run moves the belt. “It requires you to engage more, as you need to work harder to keep the machine going,” says Superstar Gym co-owner Joe DiAngelo. “You’re constantly working to power the treadmill.” Find out more at Well + Good NYC.  More from Prevention: 10 Mistakes You Make On The Treadmill  14 Walking Workouts To Burn Fat and Boost Energy  Walking On An Incline Versus Running: What’s Best?