defining characteristic of video games has long been their high couch-potato quotient. The only exercise a person could expect to get punching buttons and moving a joystick was the kind of wrist workout that put them at risk for repetitive stress injury. Playing the video game called Dance Dance Revolution, however, is nothing less than a full-body aerobic activity.

Dance Dance Revolution – D.D.R. to the avid teenage throngs who crowd the arcades to play it – is a Japanese innovation that is just now catching on in America. Like a jukebox equipped to judge your dancing prowess, D.D.R. asks players to choose from a selection of booming, beat-heavy dance-club numbers; the players are awarded points for their ability to perform the high-speed techno-tap-dance routine that D.D.R. dictates, step by step, on screen.

Players stand facing the screen on a platform divided into six-inch squares. Then, following the instructions displayed on-screen, the player must start stepping on appropriate squares. Because the steps are coordinated with the beat of the music, a successful player begins very quickly to look like an accomplished disco dancer. As players complete various steps, the machine calls out encouragement like ‘‘Wow! You are too cool!’’ and ‘‘Oh, no! You’re dangerous!’’

The nature of the game also makes D.D.R. a spectator sport: crowds gather around not to watch what’s on-screen but to see players show off their moves. And because girls tend to be socialized to become better dancers at an earlier age than boys, D.D.R. is one of the first video games since Pac-Man to attract female players in large numbers.

According to the popular Web site ddrfreak.com, there are more than 500 D.D.R. machines in the U.S.; those in New York include one recently installed in the P.S. 1 museum in Queens. Konami, the game’s manufacturer, also makes a version of the game called Para Para Paradise, in which players use tai chi-like arm movements to explode objects on-screen.

Playing D.D.R. is, it turns out, part of a healthy lifestyle. Fanatic players report often-significant weight loss resulting from the workout it provides; imagine a Stairmaster powered by quarters. The ddrfreak.com site even includes a page of tips for nonathletic types on how to reduce injury and strain when playing D.D.R. For the past several years, exercise machines have incorporated an increasing number of video-game elements. Now the arcade has begun to reach out in the other direction.