Attention, fellow sitting enthusiasts and armchair aficionados.

The “chairs” at Chaise23, opening today, do not provide a cushy spot for your butt — they kick it.

The industrial Flatiron space is the first drop-in studio to teach fitness buff/trainer Lauren Piskin’s reinvention method, which uses platforms with spring-loaded pedals and bungee cords hung from the ceiling to sculpt, tone, and exhaust muscles large and small.

Master the Pilates- and ballet-inspired maneuvers with a slow-paced beginners’ class, or get blood flowing with a cardio session (what we tried). TRX suspension cable classes (with occasional live music) round out the schedule.

We liken our class to a combo of low-impact plyometrics (one-legged balanced dips), Jazzercise (nonstop motion), gymnastics drills (press handstands, planks), and calisthenics (squats, push-ups).

You’ve been warned.

Chaise23, 40 East 23rd Street, between Broadway and Park Avenue (212-432-6100 or chaise23.com).

Photo: Courtesy of Chaise23