By David Schardt, “Want to lose weight? Then run, don’t walk,” is advice you often hear.
But is that good advice?
People who choose to run may be different—they may be more physically fit, for example—than people who choose to walk.
To avoid the pitfalls of lifestyle differences in a comparison of walking with running, Cris Slentz and his colleagues at the Duke University School of Medicine in North Carolina recruited 120 overweight or obese middle-aged men and women. They randomly assigned them to one of three exercise programs or to a non-exercising control group.
The exercisers worked out on treadmills, cycles, or elliptical trainers at an intensity equal to either walking or jogging. All were told not to change what they ate.
the study results
After six months, those who exercised the equivalent of walking 11 miles a week had lost the same amount of weight—about three pounds—as those who exercised the equivalent of jogging 11 miles a week.
The big difference between the two groups: it took the “walkers” three hours a week to lose that weight, while the “joggers” needed only two hours.
“It takes longer to burn the same amount of calories when you’re doing moderate-intensity activity like walking instead of running or other vigorous exercise,” explains Slentz.
“Intensity doesn’t have a significant effect on weight loss or fat loss,” he adds. What matters is the total number of calories you burn and that’s a matter of how hard you exercise for how long.
who lost the most weight
Not surprisingly, the third group in the study, which did the equivalent of jogging 17 miles per week—it took them three hours—lost the most weight: eight pounds over the six months. Of course, they burned the most calories.
But many middle-aged and older people won’t—or can’t—do vigorous exercise.
“If you’re lean and you can go jogging and not hurt yourself, that’s what you should do,” says Slentz. “But moderate-intensity exercise is also probably pretty darn good for you. And at the end of the day, if people like to walk, they’re more likely to walk than they are to run.”
It’s just that most people don’t do enough of the walking. “Instead of 30 minutes a day, five days a week, it would be better to do 45 minutes, seven days a week,” says Slentz.
That’s mostly for managing your weight. “While exercise can cause some modest weight loss,” says Slentz, “you can lose more by dieting.”
cardiovascular fitness is something else
For your heart and your circulation, vigorous is better than moderate-intensity exercise.
Robert Ross, an exercise physiologist at Queens University in Kingston, Ontario, showed that with a recent study.
“We had people walk four or five days a week for six months,” says Ross. They were about 50 years old, sedentary, and overweight or obese with big waistlines. “In other words, these were 300 typical middle-aged North American adults.”
The researchers randomly divided the participants into four equal groups. Two of the groups did slow, purposeful walks on a treadmill, with one group walking for 30 minutes a session and the other 60 minutes. This compared the benefits of a longer versus a shorter bout of moderate exercise.
A third group walked briskly for 40 minutes four or five times a week. This compared brisk versus moderate walking. A fourth group did no exercise for comparison.
All four groups ate a balanced, healthful diet under the guidance of dietitians. They weren’t reducing their caloric intake, but they weren’t increasing it, either.
who did the best in this study
While all three exercising groups improved their fitness, those walking at a moderate intensity improved their fitness more if they walked 60 minutes than if they walked 30 minutes.
“And the gold star went to the group that did the higher-intensity walking,” notes Ross. “Their increase in cardio-respiratory fitness was really outstanding.”
The results of this study are encouraging, Ross says, because it suggests that people have options in deciding the best way for them to exercise. “If someone wants to walk a little longer and slower, or someone wants to walk faster for a shorter time, it’s win-win because they can improve their fitness and waistline with either one.”
But if they increase the amount of walking or the intensity, they’ll see even more improvement in fitness, he says.
“Our participants were also pleased that they could increase the intensity of their exercise by simply raising the incline of the treadmill by one percent or two percent,” Ross notes. “That’s an amount that is hardly perceptible, but it makes a big difference.”
Sources: Arch. Intern. Med. 164: 31, 2004; Ann. Intern. Med. 162: 325, 2015.