From the perspective of wheelchair sports practice, there is a growing need to provide feedback on power output. Power can be used to monitor athletes' fitness and fatigue levels, thereby preventing overtraining and potential injuries, to individualize and analyze training programs, and it is also an objective measure of effort or intensity. Determining mechanical power preferably occurs without inconveniencing athletes or coaches. Therefore, this dissertation focuses on developing a non-invasive and affordable method to monitor mechanical power in daily wheelchair (sports) practice. We specifically target wheelchair basketball, wheelchair tennis, wheelchair rugby, and wheelchair racing, also known as wheeling...