* Catabolism involves the breakdown of complex molecules into simpler ones, releasing energy in the process.

* Anabolism involves the building up of complex molecules from simpler ones, requiring energy.

Glycolysis breaks down glucose, a complex sugar, into two molecules of pyruvate, a simpler molecule. This process generates a small amount of ATP (energy) and NADH (an electron carrier).

Therefore, glycolysis fits the definition of catabolism.