Hypokalemia will decrease potassium channel conductance, which will lengthen repolarization time of a nerve cell. If this gets to be severe enough, transmission of action potentials will be disrupted, and the result can be generalized weakness or paralysis because signaling to the muscles are disrupted. However, another possibility is cramping, the opposite effect, because of the same reason (being stuck in a depolarized state would also prevent the muscle from relaxing after a contraction was initiated