Nearly 98 percent of the body's creatine exists in skeletal muscle. Creatine plays a key role in the replenishment of anaerobic energy stores. After ATP is used, it must be regenerated from phosphocreatine stores during intense, brief exercise. Creatine must be available to replenish phosphocreatine stores. Some athletes consume creatine supplements, which are sold as tablets or powder, to help replenish and increase phosphocreatine stores to delay the onset of fatigue during intense exercise, as well as reduce recovery time between maximal bouts of exercise.
Creatine also is found in most meats.
Research results, though, do not consistently show that creatine improves performance for all athletes. According to ICSN, scientists have known about creatine for decades. But Reimers said the boom in creatine supplement sales began after the 1992 Olympics. Although creatine has gained popularity in recent years, there are some side effects and the safety of taking creatine for long periods of time is unknown. No creatine research has been done on youths.