creatine is retarded, if ur a competative racer i take it, then work out real hard and eat healthy, protein rich meals like 5x a day. work out like 3+ hours day, eat 4000+ cal./day, all full of protein. and drink a tittyload of water. Plus, racing is a combo of endurance, agility, and strength. u don't want to just gain hella water weight and look like a lil fat baby.
in addition, i recently read this article that found dangerous traces of metals in protein drinks, metals which take 20 years to flush out of your body. In addition it stated most people can only process 5-9 grams of protein/hour.
Conclusion: work out/train like a fiend, eat healthy protein meals, smoke weed err day.