A research shows that walking 4 miles/week can reduce your weight within a month
Depending on how much you weigh, walking at a pace of four miles per hour will burn between 5 and 8 calories every minute, or between 225 and 360 calories for a 45-minute walk. At this pace, walking 45 minutes a day most days, you can lose up to a pound a week without changing any other habits.
Maintain your heart rate while doing cardiovascular exercise
Your weight and the distance you walk determine the calories burned while walking. Walking speed matters less than distance and weight. A rule of thumb is 100 calories per mile are burned for a 180-pound person and 65 calories per mile for a 120-pound person. You can also use a Heart rate tracker.
So put on your walking shoes, turn on your iPod and go for a brisk stroll through the neighborhood.