Patients' experiences of and adherence to supervised high-intensity physical training integrated into specialised treatment for substance use disorders: study protocol for a qualitative collaborative health services study of facilitators and barriers.

INTRODUCTION: Persons with substance use disorders (SUDs) have markedly increased risk for lifestyle-related diseases and reduced life expectancy. Initial findings suggest that high-intensity physical training (HIT) represents an efficient and effective training modality for improving physical and functional capacity for persons with SUDs. However, acheiving such improvements depends not only on the availability of such training modalities but also on adherence, which remains insufficiently understood in this population. Thus, to extend the benefits of HIT to additional persons within this population, there is a need for a broader, deeper, and more patient-centred understanding of their experiences with HIT integrated into specialised treatment, including facilitators and barriers to adherence.

METHODS AND ANALYSIS: This protocol article presents an ongoing qualitative collaborative health service study where inpatients with SUDs are interviewed in-depth about their experiences of and adherence to HIT by semi-structured interview guides. Approximately 20 inpatients with SUDs will be purposively recruited based on relevant background variables and inclusion criteria to ensure breadth in experiences: 10 who have adhered to supervised HIT as part of specialised SUD treatment and 10 who have not. Depth will be supported through in-depth interviewing, reflexive field notes, and collaborative thematic analysis with persons with lived experiences.

ETHICS AND DISSEMINATION: The study has received ethical approval from Regional Committees for Medical and Health Research Ethics (Reference ID: 2019/501). By strengthening the knowledge base on factors influencing adherence and non-adherence in HIT as part of clinical practice, the findings may support patient's adherence to HIT integrated in SUD treatment in a more person-centred way, ultimately benefiting the physical and functional capacity for additional persons with SUDs. Findings will be disseminated together with persons with lived experiences via conferences, peer-reviewed publications, as well as popular-scientific communication and media. Finally, the findings may generate theoretically informative insights into patients' experiences and mechanisms influencing adherence to HIT, as well as novel concepts and insights needed for new research directions within an increasingly prioritised field in specialised SUD treatment.