When we engage in short bursts of intense activity, our muscles use a molecule called adenosine triphosphate (ATP) for energy.
ATP is the primary energy currency of the cell, but its reserves are limited. As ATP is used up, it's converted to adenosine diphosphate (ADP).
Creatine phosphate (or phosphocreatine) comes into play here.
Stored in our muscles, it donates a phosphate group to ADP, converting it back to ATP, and in turn, allowing the muscle to continue performing at high intensity for a slightly longer duration.
By supplementing with creatine, we can increase our stores of creatine phosphate, enhancing this rapid energy system.