By Howard Schneider
Tuesday, May 29, 2007

I spent some time last week looking at Tiger Woods's butt -- covered, of course. It was the starting point for Tyler Ferrell, the fitness director at Clubgolf in Gaithersburg, as he explained how to help casual athletes avoid injury and up their game this summer -- be it golf, tennis, softball or any other "rotation" sport.

Much has been made of Woods's burgeoning upper body and the role his reported 300-pound bench press routine plays in his performance. Less discussed is the view from the rear: As Woods swings, Ferrell noted during a frame-by-frame video analysis, the outline of his pants will show a set of gluteal muscles forcefully contracting as they open the hips and transfer power to the upper body and ultimately the club.

The point Ferrell made is that the power Woods and other top golfers have trained their gluteal and abdominal muscles to generate, less-fit and less-experienced players are loading onto their lower back.

To hit the ball farther, the natural tendency is to swing the arms harder and twist the shoulders more. That creates a horizontal shear force on the spine estimated in amateur golfers at 125 pounds. (The physics aren't exactly the same, but consider how you'd feel after twisting 80 or 90 times while carrying a 125-pound box of books.)

Even though pros are hitting much farther, their load on the lower back is anywhere from 40 to 80 percent less. Moving from their hips, they have placed much of the swing's stress on muscles better suited to handle it -- muscles that in many of us have weakened from years of office work and inattention.

The three gluteal muscles -- maximus, medius and minimus (sounds like a toga party) -- are far more important than the average buns-of-steel infomercial would lead one to believe. Vanity aside, they should be the body's workhorses -- responsible for lifting and carrying and twisting.

Coupled with the abdominals and other core muscles, they can surround the lower back with strength and allow a golfer or tennis player to generate a whiplike force. Add flexibility to the picture and you get a swing like Woods's, in which a line drawn from the hip to ear, roughly along the spine, barely changes position through the course of the motion.

Technique, of course, is important. A wall at one of Clubgolf's testing rooms is plastered with graphs showing how the hips, shoulders and arms of pro golfers build acceleration in sequence. But -- and here's the key for the back -- they also decelerate and stop in sequence. When Ferrell charted my swing, it was an uneven morass of lines, with the hips continuing to push laterally against the lower back when they should have been slowing down.

What to do?

A recent Golf Digest article on Woods's workout regimen noted his focus on strength and flexibility of the core muscles. There are plenty of ways to build the whole package, from stronger gluteals and abdominals to more flexible hips.

Ferrell suggests a couple of simple home tests: Sit on the edge of a chair -- arms crossed, feet on the floor, thighs parallel to the ground -- then twist your torso. If you rotate less than 45 degrees, "you're in trouble" if you are serious about an aggressive golf or tennis game.

Or try a full squat: Lower your rear end toward the ground with your feet flat, and see if you can go all the way down without tumbling over. (Careful on that point.) If you can't, then the strength and flexibility in your lower body probably need work.

Beyond that, golf or tennis training centers will offer sport-specific exercises -- torso twists using a cable weight machine, for example.

For more generic core training, both yoga and Pilates build strength and flexibility, though I'd be entering the lion's den to recommend one over the other. Try both and pick your flavor. (There is an entertaining "smackdown" between the two disciplines on National Geographic's Web site.)

Locally, the Sport and Health chain is working on a series of sport-specific Pilates classes that try to relate golf mechanics, for example, to the basic exercises. Nancy Sanchez, Pilates manager for the chain, said that the benefit to athletes goes beyond strength to muscle memory and breath control -- teaching the body how to fire sets of muscles in a deep and controlled way.

"It is not rocket science, but it is very specialized. . . . We talk about initiating movement in the core," Sanchez said.

For people trying to do it on their own, the Web site FitnessforGolf.com offers a number of exercises that need only a Swiss ball and a body bar.

Local gyms also often provide core conditioning workouts that combine elements of both yoga and Pilates with other exercises chosen by an instructor. My sessions at the Silver Spring Y are often an exercise in pain management -- but it does pay off.

As Terrell advises, "You cannot have a strong enough butt."