Gripping handlebars, Nick Piro positions his legs against a metal plate and pushes - back and forth, back and forth.

A dozen reps later, he dashes from the seated leg press to the shoulder press, the next stop on his circuit of resistance-training machines. His goal is "to get a workout, to get strong," he says, without breaking stride.

Nick, of Woolwich Township, isn't a flabby cubicle drone hitting the gym to make good on a New Year's resolution.

At 6 years old, the trim first-grader and his two brothers, age 8 and 11, are regulars at the Swedesboro, Gloucester County, Fitwize 4 Kids - a growing breed of health clubs that cater exclusively to the pint-size set.