Behavioural interventions often consist of conversations between counsellors and clients and can be a successful way to promote a healthy lifestyle. However, controlled intervention outcomes are not always successfully translated to real-world settings. A possible reason for this poor translation, is that researchers do not use information on how counsellors and clients interact with each other to explain intervention outcomes. Recently, a new method, called state space grids, has been developed to study and visualize how a counsellor and client interact with each other over time. This study will use state space grid methods to study conversations about health-enhancing exercise between counsellors and clients with spinal cord injury (SCI) to explain health outcomes. Participants receive tailored exercise counselling. Recordings of the sessions will be analysed using state space grids. The findings will help us to better study and understand how, when and why counselling is successful in changing health behaviour. These new insights can be used to develop training guides for counsellors and improve exercise counselling. In turn, understanding and improving effective exercise counselling will enhance lives of many people with SCI.