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Wireless sensor networks (WSNs) consist of large numbers of unattended sensors with limited storage, energy (battery power) and computational and communication capabilities. Because battery power is the most crucial resource for sensor nodes and delay time is a critical metric for certain WSN applications that require fast response time, data dissemination between source sensors and sinks, which is an essential activity in WSNs, should be done in an energy efficient and timely manner. In this paper, we characterize the trade-off between energy savings and source-tosink delay in order to extend the operation of individual sensors and hence increase the lifetime of the WSN, and enable sinks to receive sensed data in a timely fashion and make appropriate decisions quickly. To this end, the proposed data dissemination protocol decomposes the transmission range of sensors into a certain number of concentric circular bands (CCBs) based on a minimal distance between consecutive forwarding sensors. Then, it provides a classification of these CCBs based on their exterior radii which will help a source sensor express its degree of interest (DoI) in minimizing two metrics, namely energy consumption and source-to-sink delay. We prove that the use of sensors nodes, which lie on or closely to the shortest path between a source and the sink, as proxy forwarders, helps minimize these two metrics. Our numerical results show that the second CCB minimizes energy consumption; the last CCB minimizes source-to-sink delay; and the middle CCBs trade off between the two metrics in disseminating the monitored data towards the sink.