Regular exercise improves both physical and mental health but many people struggle to adhere to exercise programmes. Music is widely used by exercisers, and may aid adherence, but no evidence has yet substantiated this. This thesis consists of four studies exploring exercise music’s potential to assist adherence. In Study 1 (N = 282), online survey responses indicated that women were more likely to use exercise music and to synchronise movement to the beat than men, that running performance was superior among non-music users, and that music preference and personality are related. In Study 2, ten of the participants from Study 1 were interviewed, and interpretative phenomenological analysis revealed four main themes: Taking control, relating to managing the environment and internal challenges; It’s all about me, concerning individualisation and sense of self; Exercise music literacy, involving the capacity to source and access desired exercise music; and Embodiment, connected with the interaction of body, music and hardware. Study 3 (N = 60) was a correlational study, exploring relationships between individual differences, gym media use and exercise frequency. Retrospective exercise data was collected from the gym’s Fitlinxx computerised workout system, with participants supplying additional data for unrecorded exercise. Results indicated that men regularly listening to their own music exercised more frequently than those using other media. Study 4 (N = 99) was a longitudinal intervention study, comparing music and nonmusic pre-exercise interventions condition; the results indicated that listening to music prior to exercising to ‘get in the mood’ was associated with greater exercise frequency. The thesis demonstrates a music-adherence relationship: use of music both during and before exercise was found to relate to frequency of exercise. This may relate to indications that certain kinds of music evoke an ‘exercise mood.’ Combined, these studies support the use of music to help facilitate exercise adherence, and extend knowledge of the who, why and how of music use in exercise.