 at least 00 g/g, wherein the change of characteristic swelling time is Z<(τ0.0−τ0.0)/τ0.0 wherein Z is the change of characteristic swelling time, τ0.0 is the characteristic swelling time under a pressure of 0.0 psi (0.0 g/cm0) and τ0.0 is the characteristic swelling time under a pressure of 0.0 psi (00.0 g/cm0). The inventive water-absorbent polymer particles have a mean sphericity from 0.00 to 0.00