Science has established that supplementation with creatine monohydrate increases lean body mass, muscle fiber hypertrophy and strength during resistance training. These beneficial effects are thought to occur via the accumulation of creatine in skeletal muscle where it appears to stimulate transcription factors that control protein synthesis and/or increase phosphocreatine stores.
Phosphocreatine is the primary substrate used to regenerate ATP, the biological currency of energy in working muscles. Therefore, boosting phosphocreatine stores may allow for greater amount of work performed during individual training sessions and a more powerful growth stimulus. However, a recent study has shown that creatine monohydrate may enhance energy production in other ways.
Canadian researchers have discovered that supplementation with creatine monohydrate in rodents increased the aerobic breakdown of glucose and reduced the production of lactic acid. The aerobic (meaning requires oxygen) energy production pathway is the major pathway of energy metabolism that produces the largest amounts of ATP.
The accumulation of lactic acid in working muscle is a major cause of fatigue and muscle failure. Therefore creatine monohydrate supplementation may enhance energy production in working muscles in more ways than previously suspected.
Source: J Appl Physiol 2010.