Profile: You set out on foot to run errands or exercise the dog.
Payoff: If your daily strolls add up to a half hour most days of the week, you'll probably add a year or more to your life, according to one study.
Next steps: Buy a basic pedometer and aim for 10,000 steps a day (the average American takes about 5,000). Counting steps rather than minutes will encourage you to walk farther.
Push yourself: You should be breathing hard but not gasping to give your heart and lungs a good workout. Brisk walking burns 460 calories an hour; walking at a moderate pace burns 280.

Profile: You walk most days of the week, typically following a set route and going fast enough to get your heart rate up and keep it there for 30 minutes.
Payoff: A brisk walking routine will help lower blood pressure, improve glucose control, prevent heart disease, and tone the buttocks and legs.
Next steps: Gradually add some hills. It's more stressful to walk uphill, so if you have joint issues, such as sore ankles, give your body time to adjust.
Push yourself: Work on your speed by taking faster steps rather than lengthening your stride, which can strain the hamstrings and the lower back. Consider using Nordic poles. By pushing off with them as you walk, you'll build strength and stamina, according to one study. Participants burned 20 percent more calories when walking with poles.

Profile: You take challenging hikes.
Payoff: Walking on varied terrain builds strength, stamina, and balance. When you walk uphill, your energy expenditure is greater than when you're on a flat surface.
Next steps: Squeeze in several short walks during the week, aiming for a total of at least 30 minutes. In the winter, try snowshoeing or a walking video.
Push yourself: Wear a weighted backpack to get a more intense workout. Studies show that when people carry 10 percent of their weight, they burn about 5 to 7 percent more calories.

Profile: You have a safe, comfortable place to walk.
Payoff: If you use the machine's preset programs, incline settings, and a heart-rate monitor, you're probably pushing yourself to get a good workout.
Next steps: Break up your routine. Research shows that your body can adapt to the demands of a workout after six to eight weeks. Change what you do every two months—adjust the incline, ramp up the pace with a minute of jogging for every five minutes of walking, or slow down the belt and do walking lunges.
Push yourself: Take a treadmill class at a gym. National chains offer challenging ones that mix off-treadmill exercises with walking and jogging.