Published in: Butz A. et al. (eds.), Proceedings of SG 2007: 7th International Symposium on Smart Graphics, Lecture Notes in Computer Science 4569, Springer-Verlag, Berlin Heidelberg, June 2007, pp. 85-96.

Obesity and lack of physical fitness are increasingly common in adults as well as children and can negatively affect health. Regular physical activity, such as jogging or training in a fitness center, is recommended by physiologists to fight obesity and improve one’s fitness, but usually requires considerable motivation. Recently, researchers as well as companies have proposed a few fitness games, i.e. videogames where users play by performing physical exercises, in which game elements (such as graphics and gameplay) are used to encourage people to exercise regularly. This paper proposes a fitness game system which aims at combining arcade-style game graphics, physiological sensors (e.g. heart rate monitor, 3D accelerometer), and an adaptation engine. The adaptation engine considers personal information provided by the user (e.g., age and gender), her current heart rate and movements, and information collected during previous game sessions to adjust the required intensity of physical exercises through context-aware and user-adaptive dynamic adaptations of graphics and gameplay. Besides describing the general system, the paper presents two implemented games and a preliminary user evaluation, which also led us to introduce in the system a 3D virtual human.