Starch is a macromolecular polymer, and hydrolysis requires enzyme energy. Glucose will not be synthesized into starch in human body, and synthesis will also consume energy.

Aerobic respiration and anaerobic respiration, the energy released after glucose oxidation makes ADP synthesize into ATP, that is, ATP stores this energy. The reaction of releasing energy is accompanied by the generation of ATP, and the reaction of absorbing energy is accompanied by the generation of ADP.