The effect of physical activity on beliefs associated with adherence and pain-related disability in people with chronic low back pain

Background Exercise is the first step recommendation for chronic low back pain (CLBP). However, the best approach for practitioners prescribing exercise to CLBP patients is unclear, and the efficacy of exercise in reducing pain-related disability is debated. Moreover, it is unknown if any particular mode of exercise or accompanying belief about physical activity holds any effect on manipulating CLBP patient beliefs associated with adherence or pain-related disability. Aim The aim of this thesis was to investigate how CLBP patient beliefs associated with adherence and pain-related disability are manipulated through physical activity. Therefore, this thesis aimed to observe: 1) if there are any differences between individualised and general exercise prescriptions at manipulating adherence and patient beliefs associated with adherence, 2) the influence of psychosocial variables associated with pain-related disability in a generalizable sample of people with CLBP, 3) if the belief physical activity is for CLBP manipulates psychosocial variables associated with pain-related disability, and 4) to provide preliminary results and methodological consideration to a larger longitudinal observational study. Results. The RCT showed no between-group difference for clinical outcomes or beliefs associated with adherence. Moreover, both groups showed increased patient beliefs after the initial session, despite the difference in structure and information provided. Adherence was high for both groups across the 8-week intervention to both practitioner-led and home-based sessions. These results suggest both individualised and general exercise programs are feasible for mild-to-moderate levels of CLBP. The cross-sectional observational study showed psychosocial variables associated with CLBP contribute to explaining the relationship between pain intensity and lower disability in a generalizable sample of people with CLBP. Higher functional self-efficacy and lower fear avoidance beliefs were reported as important variables in explaining the relationship between pain intensity and lower disability. Furthermore, engagement in physical activity for CLBP explained the association between higher functional self-efficacy and lower disability with reporting of worst pain in the last week. Engagement with physical activity for CLBP showed reduced levels of anxiety and small effects for functional self-efficacy, pain catastrophizing, and depression compared to participants who did not report the belief their physical activity was for their back pain. Methodological considerations for difference in reporting of current and previous pain intensity and the effect of physical activity for CLBP on functional self-efficacy, pain catastrophizing, anxiety, and depression were noted for the longitudinal observational study. These considerations will allow for this future research to explore if change in these variables explain causality in pain-related disability over time