At age 44, William Stepka decided it was finally time to get back into shape. So he purchased the appropriate fitness equipment, headed out into the fresh air and in no time hurt his back - swinging a 7-iron on the driving range.

Despite its reputation as a gentle sport for players of advancing ages, golf has its fair share of walking wounded.

Each year, nearly 40,000 Americans sustain golf-related injuries, the U.S. Consumer Product Safety Commission reports. More than two-thirds of these injuries are believed to occur on the practice range.

"I think it does come as a surprise to a lot of people," says Dr. James Garrick, director of the Center for Sports Medicine at St. Francis Hospital in San Francisco. "In golf, nobody thinks much about warming up."

By some accounts, as many as six of every 10 golfers will get hurt playing the game, says Dr. Michael Fredericson, assistant professor of physical medicine at Stanford University Medical Center.

Research also has shown that amateur golfers are unable to play the game an average of 5.2 weeks a year because of chronic injuries sustained while golfing. Even pros can't escape; a study out of Japan determined that professional golfers have more arthritis in their backs than their non-golfing counterparts.

Golfers are most at risk for suffering upper and lower back injuries, and they have high rates of shoulder, hand, wrist, elbow and neck ailments, says Dr. Stephen Rice, co-director of sports medicine at the Jersey Shore Medical Center in Neptune, N.J.

"The kind of injuries that you get in golf - unless you fall out of your cart or something - are gradual onset overuse injuries," Garrick says.

Simply put, they're caused by repetitive stress on body parts given insufficient rest. And one of the biggest culprits is the driving range.

But there are other factors to blame for golfing woes. They include technical errors in the swing itself; the golfer's lack of flexibility, strength or aerobic capacity; failure to warm up before a game; and environmental conditions such as wet grass or an uneven golf course.

The environment isn't so easy to control, of course, but a golfer's swing, physical condition and warmup are.

Experts recommend a good stretching and strengthening program. And because something as simple as improper shoulder rotation during the swing can cause shoulder injuries, golf lessons are considered a must.

As players have become more savvy to the dangers of a poor stroke, they've fueled the demand for specialized programs aimed at preventing and treating golf-related injuries.

The PGA National Resort & Spa, located in south Florida, offers a golf fitness program that emphasizes stretching, strengthening, balance and conditioning. The PGA will expand its Front Nine program to other regions after it certifies fitness professionals in golf-specific training, says Randy Myers, spa fitness director.

Myers believes that soon it will be common to find exercise classes geared toward golfers in many neighborhood gyms.

One of the programs already in place is Paul Callaway's Body Balance for Performance, recommended for golfers who already are ailing. Callaway, former director of physical therapy on the PGA Tour, got the idea for the program after treating 78 percent of the Tour players over a span of three years.

"Golfers are duped into thinking this is not a (physically) stressful game, but it is," says Callaway. "It's just as devastating as a Mack truck hitting you."

Nancy Chan has been using his techniques in her Palo Alto therapy center for about a year. The physical therapist and registered dietitian evaluates clients by giving them a lengthy questionnaire, a sway test, balance test, and posture and range of motion inspection. She also videotapes their golf swings before prescribing exercises tailored to their needs.

Among her clients: beginner William Stepka, who started experiencing back pain while golfing last summer.

"We don't try to fix their swing here. We leave that up to a golf pro," Chan says. "We just try to fix their body."