When the athlete first starts to move the alactacid energy system will be used to provide most ATP, while the aerobic system begins to produce ATP by breaking down glycogen and fats. After the first few seconds, the alactacid system will decrease its production of ATP and the lactic acid system will produce most of the ATP. Once the aerobic system is fully operational (3 min) it will produce large amounts of ATP continuously, which the athlete will mostly rely upon. However, whenever an athlete needs to sprint for a fast break the alactacid system will be used, along with the lactic acid system because there is a greater demand for ATP beyond what the aerobic system is currently producing. If the higher intensity is required for extended periods, the aerobic system will increase the ATP it produces, but if more ATP is required quickly the anaerobic systems will be utilised to provide this. When intensities drop off, or the player is substituted, the aerobic system will provide the ATP allowing the other systems to recover. However, if the player sits on the bench for too long, the aerobic system will decrease its rate of ATP production and the player will be forced to go through the beginning of this paragraph again when they come onto the court.