This supports Hultman's hypothesis that creatine is likely to be most helpful when lactic acid levels are highest and fatigue is greatest. Hultman thus feels that creatine serves as a ''buffer'' lowering lactic acid muscle burn and delaying fatigue, thus allowing an athlete to perform longer workouts. There was actually decreased performance in the creatine supplementation group, which may be attributed to the participants weight gain. This aerobic metabolism occurs during more prolonged, sustained exercise as opposed to anaerobic metabolism which occurs during fast, nonsustained muscle contractions. It is therefore more likely that if creatine supplementation has an effect it will only be seen during brief, anaerobic exercise such as sprinting or weight lifting.
Companies selling creatine products claim creatine is a safe product free of side effects.
No negative side effects have been noted among research with the recommended levels of supplementation. It should also be noted that the studies that used high dosages of creatine, such as 20-30 grains daily, took. There have been no controlled studies of long-term use of high doses of creatine. Despite this, many people have safely gained muscle and increased endurance by cycling their use of creatine. Creatine supplementation per se does not enhance endurance performance.