The outstanding improvement of communication and sensor technologies has not brought us only convenience to our lives but also envisioning our promising future with no barrier. Real-time information gathering, processing and communication in sensor networks have enriched people's lifestyles as they never imagined before. Wireless sensor networks (WSN) have provided people so much convenience with its variable applications such as environmental monitoring, human-centric applications, military applications, support for logistics, and etc. Most of all, researches on wireless body area networks (WBAN) have been revisited frequently for ubiquitous and affordable healthcare as healthcare related products and applications have obtained great attention for the people who are really concerned about their health, fitness as well as well-being lives. First, this dissertation examines true optimal routing with use of a novel load balancing aware routing algorithms for multipath wireless sensor networks. We propose an innovative multipath routing network design scheme utilizing dynamic load-balancing aware feedback control system that can predict future traffic flow with preloaded traffic control. Then, we narrow down to wireless body area networks applying linear network coding design approach in both network and MAC layers. Through a discussion of the analysis, modeling, implementation, and simulation, we derive the solutions for the proposed designs that can significantly improve the reliability and energy-efficiency of the desired healthcare related systems.