Obviously you can get swim the fastest in air, because you don't get enough force to "swim" in the air when you move your hands (read: you don't float - ergo fly).
No human can swim something solid as well, d0h.
One would say that, of course, water is the place where you can swim faster, but doesn't logic tell you that the more viscosity the surroundings have the more faster you go by every pull.
So, anyone heard of such experiments where they have tested the perfect blend where it is possible to swim very fast? Must be something thicker than water i assume.