If the amount of acid becomes too great, muscle movement stops. But if you keep on regenerating ATP because of all the creatine you have, you can minimize the amount of lactic acid produced and actually exercise longer and harder. Creatine has also been shown to enhance your body's ability to make proteins within the muscle fibers. Two of these proteins, actin and myosin, are essential to all muscle contraction. So when you build up your supply of these contractile proteins, you actually increase your muscle's ability to perform physical work.
Athletes frequently divide their creatine use into two phases.
The first phase, called the loading phase, fills up the muscle fiber's storage capacity for this nutrient. This phase usually lasts five to seven days. After that, athletes reduce their creatine consumption to a lower dosage level which continues for an extended period of time. This second phase is called the maintenance phase. The amount of creatine you have in your body depends mostly on the amount of muscle you have.