The amount of ATP stored in the muscle will only fuel a maximum effort such as lifting a weight for 10 to 15 seconds. This increases the muscles capacity to do work and improves the energy efficiency of the muscle.
Intensity is necessary to achieve natural strength gains and muscle growth.
Muscle growth takes place when the muscle has been overloaded. Without heavy sets, your muscle will remain small. Creatine also buffers the development of lactic acid allowing for a more enduring workout. Research studies published in Britain's prestigious Clinical Science Journal clearly showed that athletes who took Creatine Monohydrate and exercised were able to increase the available muscle Creatine dramatically. The first phase is creatine-loading.