You burn more calories sleeping than you do watching television.
It’s called the “basal metabolic rate” or BMR. It’s the amount of energy required to maintain basic bodily functions while at rest, such as regulating body temperature, keeping the heart beating, and breathing. It’s true: just sitting on the couch staring into space requires that you burn some calories. That’s the BMR and it accounts for about 2/3 of the total calories burned each day. As examples, you burn 40-55 calories/hour while sleeping and a bit more while sitting up watching TV or reading.