Effect of Supplementation with Creatine During Aerobic Exercise Through the Creatine-Fosfocreatine Shuttle Inside the Mitochondria

Abstract
Creatine supplementation has been used as a habitual practice among athletes of various sports in an attempt to improve performance. The supplementation of creatine seems to provide a better performance at sub-maximal and maximal intensities in activities where energy is predominantly obtained from ATP-PC sources (i.e., during anaerobic exercises). Improved performance has been attributed to an increased content of muscular creatine and fosfocreatine, which would allow a faster ATP re-synthesis coupled with a decreased muscular fatigue during repeated bouts and series of exercises. However, a number of studies have demonstrated that performance of aerobic activities can be also improved by creatine supplementation. Results are controversial and further studies are required to determine the specific mechanisms. The objective of this study was to review the mechanisms underlying the effects of creatine supplementation over the performance of aerobic exercises. It was concluded that improved aerobic performance can be explained by a mechanism that shuttles creatine-fosfocreatine inside of the mitochondria and allows a better use of the energetic substrates.

Key words
suplementation with creatine, performance aerobic, suttle creatine

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