Stride Right
Keep in mind, we're talking about power walking, not casual strolling. For optimum calorie burning, you need to walk at about a 4.5 mph pace. Fitness scientists at Washington University in St. Louis found if you walk at this pace, you can burn almost as many calories (201 per 30 minutes, based on a 140-pound woman) as someone jogging at about the same speed (223 calories per 30 minutes).

Of course, 4.5 mph is a fast walk. You shouldn't expect to hit that speed right away. Begin at a slower pace and gradually work up to this speed. How do you find your beginning pace? Measure a mile around your neighborhood with your car's odometer, then walk it and time yourself. If it takes 20 minutes, that's approximately 3 mph; 15 minutes is 4 mph; 13 minutes is 4.5 mph; and 12 minutes is 5 mph. Another way to measure your pace while walking: Try to maintain the point where you're just about ready to break into a jog.

Beginners should aim for a minimum of five, 10 to 30-minute power walks a week. Try to add two minutes to your sessions each week. Remember your walking time should also include a few minutes to warm up, cool down and stretch. Don't worry if you can only manage a 10-minute walk at first. Your pace and endurance increases the more you walk.

Walk This Way
To properly perform power walking, you need to practice sound body mechanics.

• Don't walk with long strides; they're less efficient and more tiring than quick heel-ball-toe steps. Focus on landing on your heels, rolling through your instep, then propelling yourself with a push off your toes.
• Keep your neck and head in picture-perfect posture— walk with your chin up and look about 10 feet ahead.
• Bend your elbows at a 90-degree angle. Close your hands so they make fists, but keep them relaxed. Swing them in an arc from your waist to your chest, keeping them close to your body. This movement helps you walk faster, burn more calories and build upper-body strength.