Controversy Over ‘Power Moves’

Many fitness centers have incorporated bounding exercises, or “plyometrics,” into their aerobics classes. Often advertised as “power moves,” they’re used to make the workouts more demanding and varied. But some fitness experts worry that these moves may cause injuries.

The drills range from ankle hops, during which the athlete jumps upward on one foot while extending the ankle joint, to high-intensity depth jumps, during which the athlete jumps off a box, then immediately springs upward upon hitting the floor.

Sara Kooperman, owner of Sara’s City Workout in Chicago and co-creator of “The Energy Explosion!” instructor training video, has her students do what she calls controlled power jumps. “It’s an adapted form of plyometrics, to tone the muscles. We don’t go off boxes, and the jumps we do aren’t as high.”

According to plyometrics expert Richard Field, however, these exercises have no place in an aerobics class. A doctoral student in physiology at the University of New Mexico, Field has trained Olympic-class athletes in bounding drills.