During sleep, our body cells need very few calories. Because at this time we do not do any work. Only the cells of the heart , lungs , kidneys, and digestive system are constantly working, and these cells require very few calories. When we sit up, some muscle cells become active and start consuming 1 1/2 calories. When we sit down and work at the computer, our hand movements increase the need for calories. When we get up and start cooking , changing clothes and cleaning the house, our muscles become active which starts consuming 2-3 calories per minute. This is exactly how we need more calories when we move around. Normal walking requires 3-4 calories and brisk walking requires 5-6 calories. 6-7 calories for jogging and 10-12 calories per minute for brisk running. Calories are needed for every movement of the body. The more muscles work, the more calories are consumed. People who lead a comfortable life need 1600 calories. Workers who build houses or people who ride rickshaws need more calories. If an athlete develops the habit of 5-6 hours of physical activity every day, then he needs 3000 calories per day.