No, I don’t think it’s related to water. It has been suggested that it is because caffeine liberates internal calcium stores in the muscle. Calcium is required for muscle contraction, and it must be reabsorbed for relaxation. Creatine is the energy source that aids in the release or reabsorption of calcium used in muscle contraction and relaxation. So, if caffeine affects the calcium levels in your muscles, then all the creatine in the world won’t matter since the calcium which it works with has been disrupted.
The weird thing is, if caffeine liberates calcium, wouldn’t that make your contractions stronger since more calcium is available?
However, if caffeine is a liberator of calcium, does that mean caffeine makes it harder for your muscles to reabsorb calcium and relax? Since caffeine liberates calcium, it does so for all muscles in the body. This would mean, in theory, a synergist muscle that uses the calcium to contract would be affected by an antagonist muscle that needs to reabsorb calcium and relax.
When you curl a dumbbell, your triceps need to relax in order for your biceps to flex the arm. If the triceps don’t relax fast enough, then they are adding opposing tension to the flexion of the elbow thus fighting the movement meaning it will be harder to do. If this is the case, then the gains of creatine could be negated by an opposing muscle that can’t relax fast enough.
I’m not sure if I buy this theory, since it proposes that just taking calcium on its own should make you weaker? Either way, it is definitely interesting stuff. I'd really like some more definitive answers on the matter!
http://www.creatinemonohydrate.net/crea ... ter_7.html