COLORADO SPRINGS, Colo. – Your mother was right when she told you to sit up straight.

But good posture involves more than not slouching. There’s a whole science to it, as Dr. Paul D’Arezzo details in his new book, “Posture Alignment: The Missing Link in Health and Fitness.”

D’Arezzo, 51, became interested in the subject after seeing countless patients with muscle and joint complaints during his years as a emergency physician in Colorado Springs and elsewhere. After retiring from the active practice of medicine in 1995, he studied all he could find about the effects of posture.

Proper posture makes a person look younger and more confident. But it’s more than a matter of appearance, D’Arezzo says.

“Posture affects what we are able to do and what we are not able to do,” he says.

Just as machinery is designed to work within a certain alignment, so is the human body, D’Arezzo says. But our alignment can get thrown out of whack as part of a downward spiral that often occurs as we grow older.

D’Arezzo says the chief culprit is not aging, however, but our sedentary society. “We don’t move as much as we used to,” he says.

We’re sitting at desks and in cars and in front of the television. Muscles become stiff and weak from lack of use, which makes it tougher to maintain proper posture. The resulting loss of postural alignment can lead to pain, increased risk of injury and furthering of the downward spiral.

“We’ve become a nation of walking wounded,” D’Arezzo writes. “We slouch, we waddle, we sag.”

The answer? Get moving. But just hitting the gym or running around the track won’t necessarily solve the problem and could even worsen it, he says. He suggests exercises that increase flexibility, strengthen specific muscle groups and restore correct alignment. Nearly half his book serves as a guide to such exercises.

Change is gradual, D’Arezzo cautions. But the eventual payoff can include improvements in function and appearance. His book offers a detailed guide to how the body should look with “optimal alignment.”

D’Arezzo also touts the benefits of yoga, which he took up a few years ago and practices daily. Yoga, he says, promotes flexibility and teaches people to listen to their bodies.

“A lot of us have gotten out of touch with our bodies,” he says.

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