For example, your daily calorie burn rate is 1800 without doing any specific physical activity. (Its called BMR, Basal Metabolic Rate).
Now if you are burning 200 calories in running, your total daily requirement is 2000 calories.
If you eat 1500 calories a day, you save 500 calories...right? 500 calories for 7 days makes 3500 calories. So in one week, you can lose a pound.
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