Walking is Powerful Medicine

Whether you're just starting a walking program or you're already a regular walker, your health likely played a role in your decision to get fit. Maybe you want to lose a few pounds or protect your heart from disease or keep your bones strong and your joints limber. Walking can do all this and more.

But when we talk about walking for health, we must look beyond the physical benefits. After all, health is a rich fabric spun from physical, mental, emotional, and spiritual threads. If one of these threads becomes frayed for any reason, it can weaken the entire fabric. What you eat, how much you sleep, how you handle your personal and professional relationships, how you view the world and your place in it -- all of these things influence whether or not you feel vital and strong. They also have a real impact on your body.

The same can be said of walking. It supports health in every sense -- physically, mentally, emotionally, and spiritually. It enriches and balances your life. And it just plain makes you feel good. No wonder the Greek physician Hippocrates deemed walking to be "man's best medicine."

To get a complete picture of how walking supports good health, you must start at the cellular level. A daily walk keeps certain cells -- your immune cells -- tuned up for action, ready to whip viruses and battle bacteria. In fact, some experts believe that walking may be one of your best weapons for fighting off infection and disease and getting on the road to recovery fast.

Strong statement? Maybe. But a number of studies have shown that a moderate walk not only relieves the stress that may trigger or aggravate an illness but also stimulates your immune system, your body's main defense against disease. In one such study, a 45-minute walk (about 3 miles) increased the activity of certain immune cells by about 57 percent. The cells' activity level returned to normal about 3 hours after the walk.

Now researchers don't know for sure whether walking can make you heal faster, but some studies suggest that people who walk consistently develop fewer illnesses than people who are sedentary. The fact that walking is a moderate activity may be key to its immune-enhancing effects. Indeed, other studies show that long bouts of intense exercise -- like an hour of pavement-pounding, heavy-breathing running -- can actually suppress your immune system and make you more susceptible to infection.

This brings up a question that I often hear from fellow walkers: When you're under the weather, should you continue your walking program or take off a few days until you feel better? One expert recommends this rule of thumb: If you have a headache or runny nose, or if you're sneezing, you're okay to walk as long as your temperature is normal. In cases of fever, sore throat, or coughing, you should rest until your symptoms subside.

Even if you feel well enough to continue walking, skip the marathons, races, and fun walks for the time being -- unless you have your doctor's okay to participate.

If walking has a beneficial effect on the immune system, then might it have some protective effect against any type of cancer? The research so far seems promising.

In one study, laboratory rats were given a chemical that induces breast cancer. Half of the rats were put in cages that allowed them free access to an exercise wheel. The rats could run on the wheel any time they got the urge, and they did so frequently. Compared with the rats that didn't have a wheel, those that did developed one-third fewer cases of breast cancer. What's more, their tumors appeared much later.

Exercise in general keeps cropping up as a factor in cancer prevention and treatment. Scientists don't yet understand how exercise might deter tumors, but they do know that people who work out regularly seem to get cancer less often than those who don't.

For instance, three separate population studies found that men with physically demanding jobs, such as carpenters, plumbers, gardeners, and mail carriers, are less prone to colon cancer than men who sit all day. In another study, Harvard University researchers determined that men who engage in about an hour of vigorous activity every day reduce their risk of prostate cancer by 47 to 88 percent. And researchers at the University of Iowa Cancer Center in Iowa City found that women over age 65, a group that accounts for 50 percent of all breast cancer cases, are less likely to get the disease if they exercise moderately. In fact, the more active these women are, the lower their chances of being diagnosed with breast cancer.

While no one can say for certain that walking every day protects against all kinds of cancer, enough evidence has been uncovered to persuade the American Cancer Society to recommend regular exercise as one possible way to reduce your risk. And if you or someone you know is receiving treatment for cancer, walking may be the ticket to a steady recovery and the speedy return of strength and energy.

For example, walking may counteract the fatigue and weakness that are associated with high-dose chemotherapy. Traditionally, patients have been told to rest to recuperate from chemo. But extended bed rest leads to loss of muscle strength and cardiovascular fitness, which only worsens fatigue and weakness -- so much so that they can linger for years after treatment. So a team of German researchers tried a different approach: They encouraged patients to exercise regularly after completing chemotherapy. People had not only more energy but also a more positive attitude toward recovery.

The benefits of exercise for cancer patients are psychological as well as physical. One study of women being treated for breast cancer showed that their levels of depression and anxiety dropped dramatically after 10 weeks of regular exercise -- 30 to 40 minutes, 4 days a week. This finding is especially encouraging because breast cancer survivors face a significant risk of depression and anxiety.

To be sure, scientists have only begun to scratch the surface in understanding the benefits of exercise -- not only for fighting cancer and boosting immunity but also for enhancing all aspects of human health. Interestingly, most studies of exercise use walking as the activity of choice. And they have revealed some extraordinary information about what this most fundamental of workouts can do.

As you can see, you have a lot to gain just from lacing up a pair of walking shoes and putting one foot in front of the other.