A number of recent advances in MAC protocols for wireless sensor networks have been proposed to decrease idle listening. Low-Power-Listening (LPL) protocols transmit data packets for the inter-listening interval, for this reason, allowing sensor nodes to sleep for long periods of time between channel probes. The inter-listening interval as well as the particular type of LPL protocol ought to well match the network conditions. Some LPL protocols break communication between the sender and the receiver after the data packet has been successfully received. In this study, a novel variable rate based time frame scheduling scheme is proposed to further reduce collisions and improve energy saving in wireless sensor networks. During this pre-schedule slot, each node knows exactly the schedule of other neighbor nodes. Multi-rate and power scaling are adopted to achieve further energy saving by employing an acceptable rate rather than the maximum rate. Data rate is dynamically adjusted according to the traffic load of sending nodes in an energy efficient data rate to retrench energy. Compared with Z-MAC, performance in the present study proves to have better ability of local framing pre-schedule and multi-rate achieves better energy efficiency. Our results show that using the improved method of the MAC schedule provides up the enhancement of lifetime for different traffic scenarios.