The American obsession of going to the gym to revitalize stressed-out bodies is not new, says a UC Davis American studies scholar whose new book explores how our society began to link health to machines a century ago.

In "The Body Electric," Carolyn de la Peña traces the history of using machinery to renew the body back to the early 1900s, when Americans visiting health spas and gymnasiums were introduced to machines like the Zander, which regulated each motion, allowing neither too much nor too little muscular resistance.

Electrical devices and the curative powers of radium also were being touted as paths to renewed vitality and as a cure for something called neurasthenia -- a collection of mysterious ailments whose symptoms ranged from sleeplessness and anxiety to weariness and despondency.

De la Peña examines reasons Americans in the early 20th century embraced technology as a means to rejuvenate the body and suggests that the psychological effect of such acceptance led to a mythology of the technologically powered body.

Using technology to release latent energy and reverse the physical decline caused by modern society was a compelling idea: Weight-lifting machines were about releasing locked energy within the body; electricity was about transferring it into the body; and radioactivity was a way to actually alter the body, turning it into an energy-producing device.

Perhaps, de la Peña says, those early attitudes toward energy have carried over; perhaps our culture's "energy advocacy" -- its embrace over the past century of electric cityscapes, nuclear power and even larger vehicles -- has roots in Zander machines, electric belts and radium water coolers.