Question, baby boomers: Ever think of your feet as a pair of tires?

It’s time that you do, now that you’re walking/jogging/stiletto-heeling your way through middle age, according to some foot experts.

“Over the course of a lifetime, the tires start to wear down and your feet start to wear down,” says Terry Spilken, a podiatrist who has worked with the Alvin Ailey American Dance Theatre and the New York Islanders hockey team.

“It’s part of the natural process. As we get older, things change and we start getting pains where we never had pain before,” adds Spilken, of Livingston, N.J. “Just as tires need to be repaired, your feet do, too.”

This is not to say that young people don’t have foot trouble.

“We see bunions in teenagers and heel pain in very young athletes, but the bulk of the population doesn’t look at their feet and then, by the time they’re 40 and 50, they realize something’s going on,” says Steven Dribbon, chief of podiatry at Saint Peter’s University Hospital in New Brunswick, N.J., and an orthopedic surgeon who specializes in foot surgery. “Unless your foot hurts, you don’t think about it,” Spilken explains. “You don’t think about the maintenance of the foot until you have a problem.” Plus, it often takes years “for pathology to develop,” Spilken said.

Composed of 26 bones, 33 joints and an impressive network of more than 100 tendons, muscles and ligaments, our feet are more subject to injury than any other part of the human body, according to the American Podiatric Medical Association.

Our feet endure a force equal to several hundred tons just from an average day of walking, according to the association Web site, www.apma.org.

But feet don’t withstand punishment as well as they did in their (and your) youth, in part because of age-related changes.

“There’s more … injuries occurring as we get older because structures can’t withstand the same forces as they were able to years before,” Spilken says.

“The average 55- to 60-year-old tennis player never had a problem. All of a sudden, they have pain in the ankle and they think they’re spraining their ankle. But it’s just that the ligament has weakened over the years from that kind of punishment.”

“The older we get, there’s atrophy of the fat padding on the bottom of the feet, which makes the bones and the joints more susceptible to stress. It can lead to symptoms of heel pain and ball-of-the-foot pain, especially for women who wear shoes with any heel,” says Richard Braver, a sports podiatrist, foot and ankle surgeon, and foot and ankle specialist for all the sports teams at Montclair State and Fairleigh Dickinson universities.

Arthritis can creep into our feet as we age and make an impact on gait and balance. Wear and tear on our feet can cause arches to collapse. Certain ligaments and tendons have a decrease in elasticity with age, so we’re more prone to strains such as plantar fasciitis, an inflammation of the fibrous band of tissue in the bottom of the foot that extends from the heel bone to the toes. Years of walking around in ill-fitting shoes can lead to the development of painful hammertoes and bunions, which can result in deformities of the feet.

When you should see a foot specialist depends, in part, on your particular health situation. If you’re diabetic, for example, you should get your feet checked at least annually because of circulation problems that can result in non-healing wounds.

Treatments for foot problems range from simple rest to surgery. They include the use of custom-made orthotics, which are shoe inserts to help correct an irregular walking pattern, padding, shoe alterations, cortisone injections, immobilization and physical therapy.

People who don’t have a chronic condition but are experiencing pain in the feet should not delay seeking medical help.

Here’s the number one foot health tip from the American Podiatric Medical Association: “Don’t ignore foot pain – it’s not normal.”