The World Health Organization estimates between 1,600 and 2,500 calories per day for a healthy adult individual. The energy needs of each person are not the same and depend on various factors such as age, sex or body composition.
To lose that kilo by exercising in a week, you would need to eliminate about 600 calories daily. The ideal way to lose weight is to burn calories through physical activity, as we have pointed out, although these amounts would help to lose the same weight.