The time-dependent load-bearing behaviour of concrete and the considerable model uncertainties in its prediction pose significant challenges for the sustainable and material-efficient design of concrete structures. The creep behaviour is significantly influenced by the material composition and the ambient conditions, but also by the load history. The aim of this article is to illustrate the influenceability of the creep tendency of concretes and its improved predictability through the tailored application of preloads above the subsequent permanent load level. For this purpose, four experimental test series on normal concrete and polymer-modified concrete are designed, carried out and evaluated, with the main focus on investigating the influence of preloading intensity and timing. Furthermore, it is investigated to what extent the structural changes associated with the preloading affect the properties of the short-term load-bearing behaviour. The presented results will serve as a basis for further experimental, analytical, and numerical investigations to enable accurate prediction and manipulation of the time-dependent deformation behaviour of modern concrete structures, which may lead to more material efficient and sustainable design.