Creatine is made from amino acids GLYCINE, ARGININE and METHIONINE. Creatine increases muscle phosphocreatine stores which facilitate production of new ATP molecules which is the key molecule for energy production and all basic functions of life. During exercise, ATP molecule is broken down to produce energy. The rate of ATP resynthesis limits your ability to continually perform at maximum intensity.
Creatine supplement increases your phosphocreatine stores, allowing you to produce more ATP which in turn increases muscle energy and thereby boost performance.