Experimental study of shock reloading processes during the uniaxial strain loading of aluminum alloy targets reveals a dependence of reloading response of material on the particle velocity dispersion behavior. This response is found to be elastic-plastic in case the velocity dispersion at the plateau of compressive pulse equals zero. In the presence of the velocity dispersion the reloading response is pure plastic. This phenomenon is considered from the position of nonlocal hydrodynamic theory developed for description of high-non-equilibrium processes in heterogeneous media.