When asked if he stretches first, White, 33, of Pasadena Hills, Mo., said no.

"But I probably should," he added, sheepishly.

As it turns out, White has been doing things right.

In 2004, the Centers for Disease Control and Prevention reviewed 361 research studies done by the epidemiology program office and found no evidence that stretching before or after exercise prevents injury or muscle soreness. Specifically, they were looking at traditional stretching, also known as static stretching, which involves holding a stretched pose for several seconds or more. Think splits or toe touches.

Dr. William Meller, an internist in Santa Barbara, Calif., believes we can study our ancestors from the Stone Age to figure out what's good for us and what's not. Basking in the sun — for vitamin D — and eating red meat — for protein — are good, Meller says.

Stretching before rigorous exercise is not.

"Can you imagine a caveman engaging in a program of stretching before heading out to chase down prey?" he asks in his recent book, "Evolution Rx: A Practical Guide to Harnessing Our Innate Capacity for Health and Healing."

Some sports medicine experts, such as Dr. Herbert Haupt, of Orthopedic Associates in Des Peres, say static stretching inhibits performance and might even cause micro-tears in tendons, ligaments and muscle tissue.

"We recommend light stretching only after warming up," Haupt says.

Despite such mounting evidence, the traditional form of stretching before exercise is still popular.

Nick Akers, certified personal trainer with Fitness Factory in St. Louis, says he sees members at the downtown gym stretching before their workout all the time. And he often has to convince his one-on-one clients not to do it.

"It's old school," he says. "I tell them they can relax their muscles so much that their neurons aren't firing."

Akers and other sports medicine experts say that dynamic stretching before exercise is the way to go. And you do it by moving through stretches without pausing or holding a position.

You can also warm up, says Haupt, by doing your exercise at half the speed. For instance, runners would start with a slow jog and build speed. A pitcher could rotate her arms in a pitching motion and lob balls softly.

Eileen McAllister, head strength and conditioning coach at SIU Edwardsville, says a weekend warrior getting ready to play a team sport might want to spend pre-game time jogging briefly, skipping while swinging his arms and doing grapevine-crossover steps.

"They can also do a sideways shuffle to work in more planes than just forward, or walking forward while grabbing the knee toward the chest," she says.

Coaches and trainers at SIUE quit instructing athletes to do static stretches before working out or competing about five years ago, McAllister says. "Studies have shown that it decreases power and speed."

Haupt says it can be especially detrimental to athletes recovering from injuries.

"People who do suffer a strain think they'll stretch it out, but they end up making it worse," Haupt says.

"What they should do is give it some rest, avoid reloading it until it's recuperated, then work on strengthening it."

That's not to say that static stretching doesn't have any benefits.

Dr. Scott Kaar, orthopedic surgeon and director of SLUCare's sports medicine program, says stretching every day for three months would make a person more flexible. And, he says, there's evidence that it helps certain conditions.

"For instance with plantar fasciitis, stretching the calf will help and we know that for sure," he says, referring to pain and inflammation of the plantar fascia, a thick band of tissue that runs from the heel bone to the toes.

Haupt adds that it's vital for senior athletes to do traditional stretching but only after their main workout.

"Stretching is fundamentally important for the muscles around the joint to minimize arthritis and degeneration," he says. "And stretching after prolonged exercise for any athlete helps reduce lactic acid accumulation when you've really exercised the muscle."