Why is respiration considered to be an exothermic reaction?

For the survival of life, we require energy. We obtain this energy from the food we eat. The food molecules, through the process of digestion, is broken down into simpler molecule like glucose. These substances come in contact with the Oxygen present in our body cells to form Carbon dioxide and water along with a certain amount of energy (Respiration process). Since the energy is in the form of heat (that maintains our body temperature), respiration is considered to be an exothermic reaction. The reaction taking place is:

C6H12O6 + 6O2 → 6CO2 + 6H2O + Energy