Purpose: To explore how the meaning of exercise and other factors interact and influence the exercise behaviour of individuals with Parkinsons disease (PD) enrolled in a 6-month minimally supervised exercise program to prevent falls, regardless of whether they completed the prescribed exercise or not. Method: This qualitative study utilised in-depth semi-structured interviews analysed using grounded theory methodology. Results: Four main themes were constructed from the data: adapting to change and loss, the influence of others, making sense of the exercise experience and hope for a more active future. Participation in the PD-specific physiotherapy program involving group exercise provided an opportunity for participants to reframe their identity of their "active" self. Three new influences on exercise participation were identified and explored: non-motor impairments of apathy and fatigue, the belief in a finite energy quota, and the importance of feedback. A model was developed incorporating the themes and influences to explain decision-making for exercise participation in this group. Conclusion: Complex and interacting issues, including non-motor impairments, need to be considered in order to enhance the development and ongoing implementation of effective exercise programmes for people with PD.Implications for RehabilitationExercise participation can assist individuals to reframe their identity as they are faced with losses associated with Parkinsons disease and ageing.Non-motor impairments of apathy and fatigue may influence exercise participation in people with Parkinsons disease.Particular attention needs to be paid to the provision of feedback in exercise programs for people with Parkinsons disease as it important for their decision-making about continuing exercise.