Creatine
Creatine is most commonly used for improving exercise performance and increasing muscle mass in athletes and older adults. The use of creatine may also support in improving the athletic performance of young, healthy people during brief high-intensity activity such as sprinting.
Creatine use is widespread among professional and amateur athletes and the findings seem to indicate that creatine loading (using 20 grams daily for 5 days) may be more effective than continuous use.
Creatine seems to be more beneficial for power and strength sports rather than endurance events and training. However some endurance athletes have seen beneficial results (in terms of recovery) from taken Kre alkalyn (which is a has pH netural creatine).