Traditional wired monitoring systems limit the freedom of patients and also cause stress that sometimes is an incipient reason for some diseases. Hence, there is a need for new methodologies that can provide a continuous monitoring system while relieving the mentioned limitations. Fortunately recent technology advancements introduced a new technology, called Wireless Sensor Networks (WSN), suitable for many applications especially for health monitoring. We present a continuous monitoring without limiting the freedom and privacy of elderly people based on WSN technology. This system can detect life-threatening changes of older people based on comparing the ordinary daily activities with high risk behaviors, such as falling. Moreover, it can determine the location of the patient when high risk behavior is detected and sends an alarm to hospital staff or their relatives. This method is proved by experiments and implementation of practical samples on a testbed. The experimental measurements show 90 percent true detection by our system for falling down the patients.