(Photo: Courtesy of JumpLife)

• JumpLife

  404 Broadway, nr. Lispenard St.; 212-966-2604

  The humble trampoline has been making the rounds in the group-�fitness world for some time, most notably in Tracy Anderson’s classes. But JumpLife, which opened last fall, is the first gym devoted entirely to jumping (or �tramping,� if you must). Its two classes�one cardio, the other toning (from $15)�take place on 27 personal trampolines beneath a disco ball and neon lights. While the 45-minute, Top 40�fueled dance-cardio classes are high-energy enough to raise your heart rate, they’re low-impact enough to attract both twentysomethings and middle-aged women. Core work is the key to balance here, though each trampoline has an adjustable bar for gripping should you need the support.

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