As usual, mother knows best.

Her frequent admonitions to stand and sit straight — shoulders back and chest out as if we were balancing books atop our heads — is exactly what we should be doing.

Perfect posture is essential to preventing such problems as bone spurs, back pain, headaches and fatigue, according to health experts.

But in our increasingly computer-dependent work environments, it is easy to become so engrossed in a project that we instantly plop into the sloppy poses our moms were so quick to correct.

You know the childhood crimes. Slouching. Stooping.

The offenses in adulthood? Cradling the phone between the ear and shoulder. Sliding down into the desk chair as you ponder facts and figures. Hunching over a computer.

Why posture matters

A quick lesson in anatomy helps illustrate the importance of good posture.

“The normal spine is in an S-shaped curve, and when properly aligned, all the discs and bones stack up with an even weight distribution,” said Mary Fisher, assistant professor of the physical therapy program at the University of Dayton’s department of health and sport science. Slouching, for instance, places more pressure on one aspect of the bone or disc than another, causing increased stress through that area.

Over time, that can develop into boney changes and degenerative disc changes. And long-term boney changes can result in arthritis.

Look at it this way: With every inch you hang your head forward, you’re adding 10 pounds of pressure on your spine, according to Kathy Davis, a senior physical therapist at the Kettering Sports Medicine Center in Kettering. If you’re leaning two inches into your monitor, then you are essentially forcing your back and spinal column to deal with 20 extra pounds.

And 20 pounds equals a host of problems.

“The personal computer is to chiropractic what sugar is to dentistry,” said Dr. Robert Hayden, a Griffin, Ga.-based chiropractor and a spokesman for the American Chiropractic Association. “The workplace ergonomics is really sending a lot of patients our way.”

And those patients are hurting in many ways and many places.

“Poor posture can result in muscular strains in addition to long-term changes in the bones and discs,” explained Fisher. “With muscular strains, discomfort can develop in the neck, upper or lower back, with pain during long periods of sitting.”

If this persists, increased tension in the muscle can result in the sensation of a “knot” or tight, painful point within the muscle, she added. Such simple motions as rotating the neck, bending forward, or even lifting an arm, can be compromised.

With continued stresses on the discs, they can deteriorate, becoming thinner, or even bulge or herniate. Herniated discs can result in arm pain if they occur in the neck, and leg back if they occur in the low back.

Sit perfect

According to Fisher, the best-seated posture means the head is aligned over the trunk and the trunk over the hips, thereby placing the least amount of stress through the spine.

Ideally, when sitting in front of a computer, your monitor should be set at eye level so that you don’t need to look up or down too far to view the screen.

If you wear bifocal lenses, then be sure to make adjustments based on where you view the screen through your eye glasses, Fisher said.

The power of exercise

The experts agree exercise is tantamount for a strong and stable spine.

“Core strength supports your spine when you are standing or sitting” said Laurie Brodie, an occupational therapist with Kettering Sports Medicine Center.

Fisher, too, is a huge advocate of exercise, citing Pilates as an excellent way to strenghthen the core muscles.

“Strengthening the trunk muscles and practicing good aligned posture make sitting properly quite effortless.” She said just sitting on a Swiss or stability ball can help engage the core muscles and promote a neutral spine. And it’s impossible to slouch while sitting on a stability ball.

How to improve your posture

If you want to perfect your posture, then apply what occupational therapist Laurie Brodie of Kettering Sports Medicine Center in Kettering calls the 90-degree rule.

When sitting, the elbows, hips, knees and ankles should be at 90-degree angles.

“If you are short, then you need to put something underneath your feet so they aren’t dangling.”

She also suggests doing at least 20 seconds of stretching for every 20 minutes you’re seated at a desk. Squeeze your shoulders together, for instance, or do shoulder shrugs. Standing up and bending back with the hands on the hips gives the lower back a break, added Mary Fisher, assistant professor of the physical therapy program at the University of Dayton’s department of health and sport science.

Here are some other ways to keep the spine properly aligned:

• Arrange your desk properly. Get a headset for your phone, and make sure your computer monitor is centered. Arm rests should be adjusted to keep the 90-degree rule enforced at the elbows.

• Use the computer mouse on your dominant side. The mouse should be within easy reach so you don’t have to extend the arm too far to reach it, Fisher said

• Take a good look at your chair. Fisher said a chair with adjustable back support and a back that extends higher than shoulder-blade level will support the spine during long periods of sitting.

• Changing position is important in any repetitive task, according to Fisher, whether it’s sitting in front of a computer or painting a wall.

• Reassess your sleep posture. “Get a firm, comfortable mattress and sleep on your side,” said Dr. Robert Hayden, a Griffin, Ga.-based chiropractor and a spokesman for the American Chiropractic Association. “And get a body pillow and throw your knee over it and your arm over it and hug it.”

Contact this reporter at (937) 225-0671 or rmcmacken@daytondailynews.com.