Possibly effective for... Improving the athletic performance of young, healthy people during brief, high-intensity exercise such as sprinting. Many factors seem to influence the effectiveness of creatine, including the fitness level and age of the person using it, the type of sport, and the dose. Creatine does not seem to improve
performance in aerobic exercises, or benefit older people. Also, creatine does not seem to increase endurance or improve performance in highly trained
athletes. There is some evidence that creatine “loading,” using 20 grams daily for 5 days, may be more effective than continuous use. But remember, there is
still some uncertainty about exactly who can benefit from creatine and at what dose. Studies to date have included small numbers of people (all have involved
fewer than 40 participants), and it is not possible to draw firm conclusions from such small numbers. Parkinson’s disease. Creatine might slow the worsening of some symptoms in people with early Parkinson’s disease. Increasing strength and endurance in people with heart failure. Increasing strength in people with muscle diseases such as muscular dystrophy. Slowing loss of sight in an eye disease called gyrate atrophy. Improving symptoms of a muscle disease called McArdle's disease. There is some evidence that taking high-dose creatine daily can increase exercise capacity and decrease exercise-induced muscle pain in some patients with McArdle's disease.