Oh, sure it does! Creatine is the main source of fuel for the muscles on really intense and fast requirements (say a full-power sprint or trying to lift something heavy). Our body produces creatine naturally, but if we can pump the number by suplementing it's even better.
I heard somewhere that it's also used in UTI patients and elderly to keep some level o muscle mass.
RE: Mountain-bike 100km Marathon: a nutritional strategy that worked!