By leveraging sensors embedded in mobile devices, participatory sensing tries to create large-scale sensing systems. One major challenge in these participatory sensing networks is the problem of distributing sensing tasks in an energy-efficient manner. A large portion of energy is typically consumed for the exchange of tasks between the tasking server and the mobile devices, as well as for the position monitoring needed to detect whether a user is situated within the tasking area. In this paper, we mainly focus on reducing energy for receiving and monitoring tasks on the client side. We propose an energy-efficient task distribution and monitoring concept for participatory sensing system and evaluate it by means of simulation.