Oxidative system is also called “aerobic glycolysis”, “Krebs cycle”, “Citric acid cycle” and “Tricarboxylic acid cycle (TCA)”. This system is the dominant energy provider in an exercise of more than 2 – 3 minutes in duration and moderate intensity.

Using oxygen, the body breaks down glucose or glycogen through this system to generate enough ATP. One molecule of glucose yields to 36 – 39 ATPs in citric acid cycle.