Adverse side effects of the medications used to treat the symptoms of psychoses often include sedation and decreased metabolism, leading to rapid weight gain (Wilson 2008). This weight gain can lead to problems with an individual's health, wellbeing and quality of life (World Health Organization [WHO] 2010) and ability to perform necessary daily occupations (Wilson 2010). This is especially problematic for individuals with mental illness in the criminal justice system. It can be difficult to address their rapid weight gain when they are incarcerated, because physical, legal and institutional barriers prevent them from accessing exercising opportunities that are available in the general community. Additionally, negative symptoms of mental illness, such as avolition, further make it difficult for these forensic mental health patients to be motivated to participate in physical activity (Wilson 2008). The challenge for occupational therapists is to find a better match between the person, environment and occupation (Townsend and Polatajko 2007) in this scenario, in order to assist forensic mental health patients to participate in exercise within a secure setting, to improve their health and wellbeing, and potentially to assist them to lose weight. Virtual reality technologies, and specifically the Nintendo Wii system, are being investigated for their potential use in rehabilitation to assist in meeting