For purposes of monitoring and damage prognosis it is important to know the external loads which act on a structure. The knowledge of these loads enables us to make an assessment of damage after extreme events and updated forecasts of the remaining life-time. In many practical applications it is not possible to measure the forces e.g. resulting from wind loads or traffic directly. Therefore, these forces are determined indirectly from dynamic measurements. In this contribution, an updated overview of available time domain load reconstruction methods is presented. An attempt of highlighting the main advantages and disadvantages of different approaches, which are used in engineering is done. The importance of sensors type as well as their locations is considered for each approach. Finally, the methods applicability to real structures, where the online reconstruction plays an important role, is discussed.