The Wonders of Walking
The benefits of briskly setting one foot in front of the other keep growing. Now you can add sharper memory and better judgment to all the other positive health effects of walking. A study led by Arthur Kramer, Ph.D., a neuroscientist at the University of Illinois at Urbana/Champaign, recently showed that taking an invigorating walk can give brains as well as bodies a good workout. "The studies done in the past showed conflicting results," says Kramer. Some had found benefits for various aspects of thinking, some not, so he and his colleagues decided to find the answer. They discovered that aerobic activities such as walking (and tennis, biking, even pushing a manual lawn mower-anything that gets your heart pounding) increase blood flow throughout the body-including to the brain. This increased flow affects the brain selectively. "We believed that we'd see changes in those aspects of thinking that entail planning, scheduling, short-term or working memory, and tasks that require coordinating multiple skills, such as driving an automobile or preparing a seven-course meal," says Kramer. "These functions are called 'executive control processes.' "
Starting From Scratch To test this hypothesis, Kramer and his colleagues divided a group of healthy men and women, 60-plus years old, into two groups. The people they chose had not exercised regularly before the study began, and were considered sedentary. Using simple tests, Kramer measured their ability to plan, establish schedules, and reconsider choices if circumstances changed. Both groups then worked out three days a week, starting at 15 minutes a day and ending, six months later, at 45 minutes to an hour daily. Half the men and women engaged in stretching and toning exercises, the kind that do not increase blood flow but improve flexibility and strength. The others began a walking program. When they were retested at the end of the study, the walkers scored up to 25 percent higher on the memory/judgment test than the stretchers-certainly enough to make a difference in the real world. So if an improvement to your cardiovascular system isn't sufficient motivation to tie the laces on your walking shoes, think of the benefits to your mind.
Cutting Heart-Disease Risk And the evidence of cardiovascular benefits of walking is mounting. Two recent studies reconfirm the need to keep moving. One reviewed the habits of more than 2,500 men enrolled in the Honolulu Heart Program. It found that men who walked two miles a day had half the risk of a heart attack compared with those who walked a quarter of a mile. Experts say that walking helps prevent heart disease by reducing the risk of developing blood clots, irregular heartbeat, and a buildup of artery-clogging fatty deposits, which can trigger a heart attack. The second study found that walking to work significantly decreased the risk of developing high blood pressure. Although resear-chers know that mild to moderate physical activity reduces existing high blood pressure, this study showed that walking can prevent its development. Men whose walk to work took 11 to 20 minutes cut their chance of developing high blood pressure by 12 percent compared with men whose walk took 10 minutes or less. And even better, those who walked for 21 minutes or more reduced their risk by one-third. So even if you drive to work or use public transportation, park your car or get off at a station more than a 20-minute walk from your office. At the very least, use your lunch hour to go out and get moving. And what if you don't work? Easier still. Simply take a walk after breakfast and another in the evening. How much is enough? Should it be 20 minutes? Half an hour? An hour? Fortunately, choosing the appropriate amount of time to walk doesn't have to be a complex statistical computation. The Centers for Disease Control and Prevention and the American College of Sports Medicine have simplified it for you: Adults should accumulate 30 minutes of moderate-intensity physical activity on most, preferably all, days of the week. And walking at a brisk pace certainly fits into that plan. So get yourself a pair of good walking shoes, open your front door, and head out to benefit your health.
KNOW THY FEET To buy a good pair of walking shoes, "first find out what kind of foot you have," says Carol Frey, M.D., an orthopedic surgeon at the University of California in Los Angeles. Get your feet wet and then make footprints on a piece of brown paper. If your footprint looks like a pancake with toes (a), you've got flat feet," says Frey. If there's little or no connection between the front part of your foot and the heel (b), you have high arches, and if your footprint shows such a connection (c), you have normal feet. If your feet are flat, choose a shoe that has good arch support and that also controls pronation (the inward roll of your foot as it hits the ground). If you have a high arch, find a shoe with extra cushioning. To fine-tune the fit, try on shoes between a half-hour and an hour after you finish an hour's walk. If you walk in the morning, you don't have to wait until the end of the day to try on shoes. Note: They should feel comfortable the minute you put them on.
