## 4 Results and Discussion  
Studies recommend a multicomponent and personalized training approach for older adults with mobility limitations, cognitive impairment, and urinary incontinence [4, 9, 23, 76]. Although exergames contribute to increased training motivation and can be used as an alternative to conventional training, current exergames fail to incorporate interventions for all required training components in one single session. To address this gap in the literature, we developed the VITAAL exergame, a personalized multicomponent approach for the geriatric rehabilitation of older adults with mobility limitations, cognitive impairment, and/or urinary incontinence. Training requirements were evidence-based and adapted by the research team so that the training needs of the person should be optimally addressed and framed within the context of the exergame. The game design process sought to combine an effective intervention--within the specified clinical guidance--with concepts of gaming and enjoyment. The iterative design process, involving a multidisciplinary team, was crucial for the proper integration of all requirements and perspectives. We developed an exergame solution comprising interventions for strength, balance, cognition, and pelvic floor muscle training. The clinician could specify the training times of each component, such that the intervention could adapt to the individual training needs of the patient. A set of progress bars provided information on training completion, guiding the player through the themes and ensuring the fulfilment of training needs as defined by the therapist. Other existing solutions relied on the player to control training times, assuming compliance with verbal or written instructions given by the therapist [48, 49, 50]. Our solution could manage training times automatically based on training requirements (obtained from the clinician portal) and player training times. Ideal game experience and intervention requirements had to be balanced with the technical constraints on a take-home solution. For instance, the interaction--defined based on the movements that would suit an effective intervention--constrained the game narrative and user interface, as commands were limited to the four directions (plus the additional movement--calf rises--to access game menus). Moreover, driven by the requirement of providing an effective clinical intervention with a sustained and rich user experience, we avoided a game design based on linked stories and favored an implementation with unlimited replay value. On one side, we dropped all potential advantages of having linked stories--concerning engagement, motivation, etc. [77]; on the other side, we created a self-sustained concept: if it is sufficiently engaging and motivating, there is potential for continued play [78]. To improve game experience and user motivation, we have incorporated other gamification construction elements, such as feedback, progression, time constraints, and score [43]. According to [69], it is important to ensure an adequate level of gamification, as excessive elements may distract users from the main purpose of the activities. By design, the exergame allows the seamless integration of new contents, possibly contributing to sustain players engagement in the long-term [78], or even adapt the exergame to other disabilities. Many exergame solutions use floor plates to support player interaction with respect to their movements [40]; others use handheld devices--e.g., the Wii Remote--that work as remote controls to interact with the game interface [40]. To evaluate full-body movements, Kinect is usually the preferred choice [31, 44, 47], although accuracy drops when more complex movements are executed [52]. In a previous work, four inertial sensors were used to track upper and lower limb movements, which added some complexity regarding interaction and system setup [45]. Yet, inertial sensors were considered a viable approach to monitor movements in the context of exergaming [45; 79].