The more you move your body the more calories you burn. To lose a kilogram of fat you need to burn 8,000 calories (1 pound of fat = 3,500 calories). Walking briskly is a good way to start increasing your physical activity if you are obese. Combining increased physical activity with a good diet will significantly increase your chances of losing weight successfully and permanently!
Try to find activities which you can fit into your daily routine. Anything that becomes part of your daily life, weaved into your existing lifestyle, is more likely to become a long-term habit. If you use an elevator, try getting off one or two floors before your destination and walking the rest. You could try the same when driving your car or taking any form of public transport - get off earlier and walk that bit more.
If any of your regular shops are within walking distance, try leaving your car at home. Several surveys indicated that the majority of urban car trips outside the rush hours are less than a mile long - we can all walk a mile, and should!
If you are very obese, are unfit, or have some health problems, make sure you check with a health care professional before increasing your physical activity.