Our fitness expert answers common questions about walking
Credit: David Martinez

How many days should I be walking?
Aim for a minimum of 20 to 30 minutes a day, three to four days per week. But there's no harm in walking seven days a week, especially if it's your only form of cardiovascular exercise.

What if I have bad knees or joint problems?
Walking benefits people with minor knee problems since it is low impact. However, if you find walking bothersome (and you don't have a knee injury), try walking on a softer surface, such as a dirt trail rather than a concrete sidewalk, and avoid uneven surfaces. Or walk on a treadmill, which both softens the impact of your steps and provides an even surface.

What should I look for in a walking shoe?
Proper fit is most important. Select a shoe with a toe box wide enough to allow toes to wiggle freely with about 1/2 inch between toes and the end of the shoe. Shoes should not pinch or bind anywhere on the foot, nor be so large they slide at the heel. Also, make sure the shoe is breathable, fairly lightweight, has a supportive, cushioned heel, and a flexible sole.

How long should I keep shoes?
Replace them about every 400 to 500 miles, but periodically examine shoes for wear-don't wait for holes to appear. The outer edge of the heel and under the toe where you push off are the first places to show aging. Keep a second pair of shoes on hand, and alternate the days you wear them to help them last longer. It allows compressed areas to spring back to shape.