Neither total displacement (A), fast time constant (B), slow time constant (C), nor elastic response stiffness (D) differed between sham and either 1x or 3x, or between males and females. (E) A significant interaction effect was found for fast response stiffness (associated with IVD bulge), with male IVDs exhibiting a significantly greater fast response stiffness than female IVDs after 3x injury. (F) Unlike fast response stiffness, slow response stiffness (associated with fluid exudation) did not have a significant interaction effect (p = 0.0511) (n = 6–8, p values for 2-way ANOVA effects shown below each graph).