The moment you start moving, you start burning fat. Just sitting up gets you burning more calories than if you were laying down. Obviously, the moment you start walking that rate increases further and the faster you walk, the higher the rate at which you are burning calories. So does this mean that the best way to burn fat through walking is by walking faster?
Actually, I believe that the advantage of walking over other forms of exercise is its gentleness. If you were most interested in burning fat, there are many exercises that you can do that would work faster.
Walking however allows you to walk every day by being an activity easily adjusted to your well-being and energy levels.
The best way to walk to burn fat is to take advantage of this characteristic and use it to your advantage. Basically, when you exercise you lift your metabolic rate. After you stop exercising it slows back down but this is a gradual, not immediate, process. Lifting your metabolic rate regularly reduces the time at which you are at ‘resting metabolic rate’. Daily exercise is ideal for exploiting this fact.
Many exercises are difficult to do every day – if you are particularly tired it is unlikely you will find the energy for a run or a swim, or if you have a congested nose it is difficult to do cardio exercise. Walking on the other hand can be easily adjusted to your condition on the day.
For example, your walk could be a short, medium paced walk on an even path one day, and a strenuous, fast paced walk up a steep hill the next day. Not only do these variations have a different effect on the energy you require but they also use different muscles. You can also change the overall exercise you receive just by swinging your arms when you walk or carrying light weights. Change your walk path to include a set of stairs (remember, going up stairs uses different muscles to going downstairs) or a hill. When using a hill to add variety you can alter it even further by sometimes taking the hill backwards. All of these little variations allow you to increase the number of muscles being exercised and to keep you motivated to keep walking.
Also be conscious of your posture when you are walking. By standing straight and holding yourself well, you activate core muscles (those that are the focus of pilates workouts). This strengthens your body and helps you build these muscles. As muscles burn more energy than fat, any muscle building is a good thing.
So the best way to walk to burn fat is to walk regularly and vary your course to include the use of different muscles and to alter the stamina and fitness required.