Gyrotonic Expansion System

PRODUCT Exercise machine with pulleys and weights that strengthen and increase flexibility through fluid, dancelike moves

HOW IT STARTED Looking to build a machine to perfect the dancer's pirouette, creator Juliu Horvath stumbled on an exercise fad instead

JUDGMENT CALL A killer workout, yet too costly and complex for widespread use. But it might achieve a Pilates-type niche

Fitness buffs getting bored with StairMaster are discovering a new twist in exercise machines, the Gyrotonic Expansion System (GXS). Popular in Europe and used in some 150 exercise and dance studios in the U.S., the machine looks like a cross between a postmodern sculpture and a medieval torture rack. There are two parts--a 7-ft. pulley tower with leather straps for hands and feet and a movable bench with two rotating disks attached to its edge. Together they work in synch to stretch, strengthen and increase range of motion. Gyrotonics combines elements of Kundalini yoga, dance and Tai Chi, but it feels closest to synchronized swimming. Instead of linear back-and-forth movements, GXS offers more than a hundred variations, most of them circular and three-dimensional.

Developed by a former Romanian ballet dancer, gyrotonics is popular among dancers and athletes, but it has also been used in Germany to help elderly patients with osteoporosis and spinal injuries. Mastering the machine isn't easy or inexpensive: it typically requires six to 10 one-on-one lessons, at $45 to $75 an hour. A smaller, foldable home version will be introduced in two months (available on www.gyrotonic.com) with an instruction video. Target price: a measly $1,200.

--By Carole Buia