Take a Walk

Despite the Proven Benefits of Walking, the Nation Remains Unmoved. It's Time to Step Up

By Suz Redfearn
 The Washington Post, October 1, 2002

If a pill could significantly lower the risk of heart attack, diabetes, stroke, osteoporosis and breast and colon cancer while reducing weight, cholesterol levels, constipation, depression and impotence and also increase muscle mass, flatten the belly and reshape the thighs even as it reduced the risk of age-related dementia and made you better-looking -- and had no negative side effects -- there would be panic in the streets. The American economy would tip into chaos. The military would have to be called in to secure supplies of the medication.

Luckily, there is no such pill.

But a large and growing body of credible research demonstrates that taking a good walk most days of the week can deliver all of the health benefits cited above and more (although we admit the "better-looking" part is harder to prove).

Yes, walking. You know: one foot in front of the other, repeat, rinse, repeat. A mode of exercise formerly considered the domain of the elderly, the infirm and others incapable of or unwilling to do anything more brow-dampening.

What's difficult to figure is why so many people -- including several of the individuals who have labored to produce this special issue of the Health section (!) -- do not bother to do it.

According to the Centers for Disease Control and Prevention (CDC), somewhere near 75 percent of the U.S. population fails to get 30 minutes of daily exercise, whether that's walking or some more strenuous form of sport or recreation. Approximately one-third live a life offically defined as sedentary.

Worse is the recent news that 30 minutes a day may not be enough. Last month, the National Academy of Sciences upped the ante, telling Americans to aim for 60 minutes of moderately intense activity per day. The CDC estimates that only 3 percent of Americans exercise 60 minutes a day.

Why we're not out there walking is a mystery. It is, after all, virtually free, safe, pleasant, easy to do and hard to get wrong. It requires no special equipment except (maybe) a pair of shoes. So why are we Americans avoiding it (and other less popular forms of moderate physical exercise) to the point that we're creating an epidemic of obesity and scary upticks in the many diseases and conditions associated with it?

Could it be that we've filled our lives so full of work and other obligations that we have no energy left for the one thing most likely to keep us strong and healthy for the daily battle? (Sure.) Can it be that our communities and cities have been engineered in ways that discourage or punish those who try to walk? (Yup, that too.) Can it be that nobody's figured out how to make much money from other people's walking habits, so there's no great commercial force urging us to walk, nothing comparable to the marketing efforts trying to get us to drink sodas, order pizzas and buy new cars? (We think so.)

And can it be that some people just haven't had a recent reminder about all the good things walking can do, haven't heard some expert opinions on how to go about it and haven't checked out all the resources they can use to begin walking to improve their health? (We hope so, because that's what we're providing in the Health section this week.)

How Walking Works

Accepting that an activity as basic as walking can have powerful benefits may require updating your thinking about exercise.

"We used to think that exercise had to hurt, and you had to bleed and throw up to accomplish anything," said Susan Johnson, director of continuing education at the Cooper Institute in Dallas, which studies the link between personal habits and health. "We now know that's not true." (See "What Research Shows" for citations of the key research demonstrating the benefits of walking.)

But all of the research fails to answer the question of how something so simple can have such salutary effects.

As soon as you take that first step, a host of metabolically significant events is set in motion inside your body.

According to Greg Heath, lead scientist in the CDC's physical activity and health branch, early in your walk your adrenal glands begin secreting adrenaline, which gets into your bloodstream and signals your heart to beat faster and causes your blood pressure to go up. The heart then begins to pump more blood away from the chest and into the muscles of the limbs you're using to get yourself down the street. As a result, blood vessels in the arms and legs begin to expand as they're fed more nutrients and oxygen by the blood.

As your heart rate climbs, you're taking more breaths per minute, sometimes increasing your oxygen intake to 10 times the amount you'd be taking in if you were sitting still. As the muscles receive more blood, they begin to use up carbohydrates and sugar starches they've stored. Metabolism -- the process by which the body breaks down materials and converts them to fuel -- speeds up. As a result, so does digestion.

All this activity causes the brain to release endorphins into the bloodstream. Endorphins, which have chemical properties similar to opium, are responsible for blocking pain and ushering in that cozy sense of well-being you feel as soon as your walk ends. Additionally, exercise causes the brain to release an abundance of the neurotransmitter serotonin, which works to elevate mood.

"Methinks that the moment my legs begin to move, my thoughts begin to flow."

Henry David Thoreau

And that's all during the course of one walk. If you walk regularly, you can expect exponentially more benefits. Explains JoAnn Manson, director of preventive medicine at Harvard's Brigham and Women's Hospital, your heart muscle will grow stronger and better able to deliver more oxygen to the body during periods of rest. The lungs, capillaries and vessels along the oxygen transport pathway will expand to handle more capacity, bringing more oxygen to more parts of the body more often, a process that has been linked to reductions in risk of cardiovascular disease.

Blood pressure drops within 24 to 48 hours of exercising, and will stay down with continued exercise. The risk of blood clots also drops and stays lower if you keep the walking up. Circulation improves, which makes digestion more efficient. The body becomes better at getting glucose into the muscles where it's needed, thus smoothing out blood sugar levels and helping the body process fat. The body gets better at converting fat into energy, so you lose weight more easily than with dieting alone.

In addition, regular walking, especially the more vigorous sort, increases lean muscle mass, which consumes more energy than a similar amount of fat, thereby helping you maintain a healthy weight.

Regular exercise can also help you sleep better, which in turn delivers its own set of health benefits.

All of which is to say, once you get going with a regular walking program, your body becomes a kind of self-improvement machine.

As You Like It

Walking sessions can be toned down or ginned up, depending on your health goals and physical abilities.

To raise your cardiovascular fitness level, you need to elevate your heart rate to 60 percent to 80 percent of its maximum. This can usually be accomplished by walking briskly, as if you are late to an appointment. Those seeking to lose weight should look to keep their heart rates less elevated but for a longer time. (See suggested four-week walking programs on Page F5.)

To equal the aerobic workout that runners get, walkers need to go a little farther a little more often than runners. A recent Cooper Institute study showed that walkers had to exercise for 40 minutes four times a week to equal the aerobic benefit runners got from running for 30 minutes three times a week.

"That's a real good tradeoff for most walkers," said Johnson.

Or you could go the 10,000 steps route. Barbara Moore, president of Shape Up America, founded in 1994 by former surgeon general C. Everett Koop to provide science on the benefits of exercise, says 10,000 steps a day is a good goal to shoot for if you're trying to get fit.

Spring for a pedometer (see "How Much of This Stuff Do You Really Need?" Page F3) and clip it on your waist from morning to bedtime. Moore says a broad body of studies has shown that walking 10,000 steps a day -- either via 10-minute bouts here and there or through lengthy loops around a track or your neighborhood -- is associated with a range of health benefits.

Those 10,000 steps will translate into a different distance for each person, but for Moore they equal about five miles. The typical office worker, she says, averages 2,500 to 5,000 steps a day. For those who are daunted at the prospect of doubling their steps and maybe doubling them again, Shape Up America offers details on starting a 10,000-step program (www.shapeup.org).

"My grandmother started walking five miles a day when she was 60. She's 93 today and we don't know where the hell she is."

Ellen DeGeneres

For the vast majority of Americans who are not faced with a prohibitive disability, walking is the best choice as a regular form of physical activity, says Mark Fenton, whose roles as host of the PBS series "America's Walking," former coach of a national racewalking team and author of "The Complete Guide to Walking for Health, Weight Loss and Fitness" (The Lyons Press, 2001) make him America's reigning guru of walking.

Particularly for the 60 percent of Americans carrying more poundage than they should, walking is a safer choice than running, said Fenton. The reason: impact. A walker lands with only one-fifth the force of a jogger or an aerobiciser. Besides, adds Jon Schriner, medical director of the Michigan Center for Athletic Medicine and a spokesman for the American College of Sports Medicine, so many people already have problems with their hips, knees and ankles that they couldn't run very far or very often if they tried.

Fenton adds that walking is something you can do even when your life circumstances have been changed -- when you're pregnant, injured or older. Most people remain capable of walking throughout life, even if they have to do it more slowly or with assistance. (Of course, some people do lose the ability to walk due to accidents, disease or infirmity.) This makes it something people are likely to stick with: Only 25 percent of those who walk for exercise quit, estimates the Cooper Institute, compared with 50 to 60 percent of people who start other exercise regimens.

If all these reasons seem too self-centered, try this one: civic activism. A community that has plenty of people walking around, says Fenton, is usually a safe community and an economically vibrant one, as walkers tend to keep their eyes open and partake in a bit of retail along the way. It's also full of the kind of social interaction many other communities lack, as chance encounters lead to conversation and greater awareness about the other people in the area.

Which is to say, in addition to everything else, walking can make the world a better place. But don't worry about that for now. Look up. See the nearest door leading outside? That's your first target.