Many studies have clearly shown that creatine supplementation
enhances performance and strength gains, but some athletes and trainers are reluctant to use creatine because of concerns related to side effects. Some of the common concerns are related to muscle cramping, which in turn may be related to dehydration. A recent very well controlled study examined the effects of creatine supplementation on a host of markers related to hydration status, thermoregulation, and symptoms of heat illness during exercise in the heat. The subjects were health men who supplemented with 21.6 g/day of creatine or placebo for 7 days in a cross over design with about seven weeks between treatments. After seven days of supplementation, subjects performed prolonged exercise in a heat chamber in a dehydrated state. There were no significant differences between creatine and placebo in any metabolic, cardiovascular, or thermoregulatory responses to exercise in the heat. Further, creatine was not associated with increased symptoms of cramping nor did creatine compromise hydration status. These data provide strong evidence that creatine supplementation
is safe and does not contribute to an abnormal hydration status or response to exercise in the heat.
Watson G, Casa DJ, Fiala KA, Hile A, Roti MW, Healey JC, Armstrong LE, Maresh CM. Creatine use and exercise heat tolerance in dehydrated men. J Athl Train. 2006 Jan-Mar;41(1):18-29.