Walking to lose weight is so common that you’d think all you need to do is, well, walk to lose weight. Not true! Plenty of people walk and never see the results they expect. But we know the walking plan that will let you meet—and maintain—your weight goals…

How long to walk: The goal for losing weight is at least three hours of walking per week. Why? A review of 22 studies on walking for weight loss found that was the minimum number to decrease fat and lose, on average, 10 pounds over 12 to 16 weeks. While that’s not even one pound lost per week, it’s noticeable, and it was all due to the walking—in these studies, there were no changes to the participants’ diets. If you walk and cut calories, you can lose weight faster. And if you walk more than three hours per week—ditto.

As you lose weight, your metabolism may slow,  and you’ll have to work harder to maintain the weight loss, said Susan Besser, MD, a family physician with a secondary specialty in obesity medicine. In fact, she recommends increasing walking to five hours per week once you’ve reached your weight goal in order to keep the weight from coming back. You can break that up any way you like, such as five 60 minute-walks or even daily nuggets of 10-minutes six times a day.

How often to walk: If the only way you can fit in at least three hours a week is to walk, say, an hour and a half on Tuesdays and Thursdays, that’s much better than nothing. But it’s better by far to walk at least five days every week. The reason: By walking regularly, you will more effectively raise your level of fitness. And among the many benefits of being fit is this particular winner: A fit body tends to have more muscle, and muscle burns more calories than fat.

How fast to walk: Walk briskly—that means covering a mile in 15 minutes. Work up to that pace if you need to. Here’s an easy way to tell if you’re going fast enough for your ability: You should be able to have a conversation while walking but not whistle or sing. And do the whistle test every two weeks or so. It will let you know if you’re walking at a pace that’s brisk enough to keep losing weight—speed up if whistling’s a breeze.

To stay motivated, vary your walking route at least every two weeks. Challenge yourself periodically by walking additional hills or going a longer distance in the same amount of time.

To be an even more effective walker, read “Do You Walk Wrong? 7 Mistakes That Can Sabotage Your Walking Workout.”