Creatine Phosphate system
The creatine phosphate system is an immediate energy system. ATP (adenosine triphosphate) is created without the presence of oxygen for short, fast bursts of power and energy. This is the first system used when performing any sporting activity. However this short burst of energy only lasts for a short moment in time for round about 10 seconds. Running events like the 100 meters sprint would be an example of using the creatine phosphate system. During the creatine phosphate process, the phosphate from the ATP splits and the energy is released into the muscle. This is caused by an enzyme called creatine kinase. ADP is the result of this chemical reaction (adenosine di-phosphate). The resulting energy is used to regenerate ATP from ADP and another free phosphate.
Lactic Acid System
Like the creatine phosphate system, the lactic acid system also is a short term and high intensity energy system. Glycogen which is stored in your muscles is broken down into glucose to be used as an energy source for the contractions in the muscles. ATP plays a role in this system as well as it converts the glycogen into glucose. This specific energy system is an example of anaerobic respiration as it does not require oxygen like the creatine phosphate system. When the ATP-PCr system fades after 10 seconds, the lactic acid system is introduced. Anaerobic glycolysis then occurs which sees glycogen being broken down and lactic acid being formed as a bi-product. The lactic acid is then diffused into the muscle tissues which make them feel fatigued. This energy system usually lasts for 3 minutes. At this point your muscles would feel very fatigued and you wouldn’t be able to carry on performing the activity.
Unlike the previous two energy systems, the aerobic energy system is used over the course of longer and less intense exercises. This energy system requires oxygen to break down glycogen and fatty acids in large amounts to