As an athlete, you must be physically, as well as mentally, ready for your sport. As a Strength & Conditioning coach, it is my job to have athletes physically prepared. Conditioning's main objective is to train the energy system specific to the sport being played. In order for conditioning to be effective for the athlete, and coach for that matter, training must happen at the same level and time frame as the athletic competition.
Adenosine triphosphate, aka, ATP, is the immediate chemical energy source for all muscle contractions. We get it from the food we eat. There are three energy systems that supply the ATP: (1) ATP/CP, (2) non-oxidative, & (3) oxygen.
When designing a conditioning program, the key is training the athlete for his or her specific sport. This is done by targeting the correct energy pathway. As seen above, there are three distinctly different energy pathways. Each provides ATP, just at different levels of intensity and duration. To get the most out of your conditioning program, choose one that simulates game-like conditions by training the proper energy system.