Energy efficiency is the major point of consideration in Wireless Sensor Networks (WSN). The protocols of Media Access Control (MAC) layer provide the most effective energy utilization. Idle listening is a major source of energy wastage in wireless sensor networks; the nodes do not remain in the idle listening state when no data is available to them. Lowering the duty cycle reduces the active period of the sensor nodes; a fixed duty cycle does not adapt to the varying traffic rate in sensor networks and a high duty cycle results in significant energy wastage when traffic rate is low. For a low traffic load, low message data delivery and long queuing delay occur, in fixed synchronous duty cycle increasing the possibility of collision. A basic mechanism is followed in this paper to achieve energy efficiency due to low duty cycle for periodic traffic. Moreover, we have aimed to reduce the energy cost of sensor nodes using Simple Energy Aware Medium Access Control (SEA-MAC) protocol. The performance enhancement work has been analyzed and validated in Network Simulator (NS-2).