Jan. 12, 2004 -- Preventing weight gain may be as easy as taking a walk.
New research suggests that walking as little as 30 minutes a day or 12 miles a week may be enough to keep extra pounds at bay or even lose weight -- all without dieting.
Modest Activity Fights Obesity
More than half of Americans are overweight or obese, and the prevalence of obesity has increased by nearly 50% from 1991 to 1998. Obesity is associated with a variety of health problems from heart disease to diabetes, but researchers say extra fat around the midsection can be especially hazardous to your health.
Although diet and exercise are widely known to help promote a healthy weight, researchers say it's unclear just how much exercise is needed to prevent weight gain.
In this study, which appears in the Jan. 12 issue of the Archives of Internal Medicine, researchers compared the effects of three different exercise programs vs. no exercise at all on the weight and waist circumference of 120 sedentary overweight adults.
Each of the participants were told not to change their diet and was assigned to one of the following three exercise intensity groups or a fourth group that did not exercise for eight months:
- High amount/vigorous: Equivalent to jogging about 20 miles per week at 60%-80% of maximal heart rate
- Low amount/vigorous: Equivalent to jogging 12 miles per week at 60%-80% of maximal heart rate
- Low amount/moderate: Equivalent to walking 12 miles per week at 40%-50% of maximal heart rate
Not surprisingly, researchers found that the more the participants exercised, the more weight they lost.
But the low-amount/moderate intensity groups also showed significantly greater improvements than the non-exercise group. For example, compared with the non-exercisers, all groups significantly decreased their waist measurements.
These findings strongly suggest that, absent other changes in diet, a higher amount of activity is necessary for weight maintenance, write researcher Cris A. Slentz, PhD, of Duke University Medical Center, and colleagues. "Most individuals can accomplish this by walking 30 minutes a day."