When you exercise, your body needs energy to fuel your muscles. One of the ways your body produces energy is through the breakdown of ATP (Adenosine Triphosphate). However, your body can only store a limited amount of ATP, so it needs to regenerate ATP quickly in order to keep your muscles working.
One way your body does this is by breaking down Creatine Phosphate (CP). CP is a high-energy molecule that can donate a phosphate group to ADP (Adenosine Diphosphate) to form ATP. This process is called phosphocreatine or creatine phosphate energy system.
This system is most effective during short, intense bursts of exercise, such as sprinting or weightlifting. After about 10 seconds, your body will start to rely on other energy systems, such as glycolysis, which breaks down glucose to produce ATP.