You may have heard of the fat-burning zone, which is defined as exercising at about 55 to 65 percent of your maximum heart rate, or MHR. Your MHR is 220 minus your age. When exercising within the fat-burning zone, your body tends to burn the highest percentage of calories – about 60 percent – from fat compared to other exercise intensities. A moderate walking pace of about 2 to 3 mph is intense enough to put the average person in the fat-burning zone during a walk. To be sure it’s the right speed for you, check your heart rate periodically during your walk to see if it falls in the 55 to 65 percent range.
There are a couple ways to track your walking speed when off the treadmill. There are several smartphone apps that offer a simple speedometer to help you track speed while you walk. You can also use a cardio watch that tracks heart rate, speed, steps and other useful health stats. A third method is to use a simple breathing test. If you can hold a conversation with a walking partner without gasping for breaths, you’re walking at a moderate pace in the 2 to 3 mph or less range. However, if you find that you need to gasp for breaths every sentence or two, you’re walking at a more intense pace of 3 to 4 mph, or possibly higher. As a reference, a light jogging speed is around 4 to 5 mph.