Pumping Iron Jr.

By Ian K. Smith, M.D.

I remember the first day I walked into a YMCA weight room, a scrawny kid just entering those joyous years of puberty. There was a tinny radio in one corner with a coat hanger for an antenna cranking out the Bee Gees. Bulked-up men were whistling the tune to Saturday Night Fever as they heaved and bench-pressed rusty iron. One of them glanced at my skinny legs and rumpled socks. "Be careful," he warned me. "At your age, this could stunt your growth."

This, at the time, was a widely held view. Even today many doctors counsel preteens and teenagers against weight lifting. Some believe prepubescent athletes lack the necessary levels of circulating androgens--hormones like testosterone that help build muscle--to benefit from strength training. Others fear that overdeveloped athletes will lose the flexibility and range of motion necessary for optimal performance. And because strength training can be dangerous, some are worried it could expose young athletes to unnecessary injuries.

But that view is changing. Recent studies have shown that young athletes can effectively participate in resistance-training programs without increasing their risk of injury. The key, according to a study in the Journal of the American Academy of Orthopaedic Surgeons, is designing a program that takes into account the child's age, size, experience and chosen sport. Not only are the experts saying it's O.K. for a child as young as seven to participate in strength training, but they're also beginning to dispel some of the misconceptions about its risks and benefits.

It's true that thousands of strength-training injuries afflict children each year. But at the same time, more and more young athletes are safely increasing strength and performance on the athletic field. What makes the difference? A lot of it has to do with supervision. You can't just fill up the basement with heavy machinery and leave the kids to figure out for themselves how to use it.

Before any child begins a strength-training program, parents should run through a simple checklist. First, the child must be able to follow instructions. Second, he or she should be taught the rudiments of proper technique by a professional accustomed to working with children (and not by the kid next door). Third, realistic goals should be set. Finally, the child should be checked by a physician to make sure he or she is both physically and psychologically prepared to handle this type of program.

It's important not to lift too much too fast. Children should work out only with a weight they can lift eight to 12 times for three sets without completely exhausting their muscles. Exercise intensity can be increased in 1-lb. or 2-lb. increments while the number of repetitions remains constant. The best lifts are multijoint exercises that train major muscle groups such as the calves, hamstrings, quadriceps, pectorals (chest) and deltoids (lateral arm).

There are some lifting maneuvers that children should avoid: power lifts and squats are dangerous, even for adults.

Strength training can be safe and fun, but as in anything else, moderation is key.

Dr. Ian is a medical correspondent for NBC's Today show. E-mail: [email protected] More on weight lifting: time.com/personal