Abstract
INTRODUCTION: There is strong evidence indicating interactions between sleep and chronic low back pain (CLBP). However, evidence on the effect of exercise training (first-line treatment for CLBP), especially of specific modes of exercise training, on sleep is limited. This study aimed to investigate the effect of two exercise-based interventions (general strength and conditioning [GSC] and motor control and manual therapy [MCMT]) on sleep quality in adults with CLBP. METHODS: We conducted a two-group parallel (1:1), randomised controlled trial. Forty adults (mean age [SD]: 34.7 [6.1] years) with CLBP were randomised to receive either GSC (n=20) or MCMT (n=20) for 6 months. Sleep quality and its sub-components (e.g., sleep disturbance, sleep duration) were measured by the Pittsburgh Sleep Quality Index (PSQI). Analysis employed an intention-to-treat approach and group-by-time effects were assessed with mixed linear effect models. RESULTS: Both GSC (PSQI mean change [95%CI]: -1.58 [-2.70, -0.46] points) and MCMT (-1.61 [ 2.79, -0.43]) improved sleep quality at 6 months, but no group-by-time effect was detected (β [95%CI]: 0.03 [-1.60, 1.65]). For sleep quality sub-components, GSC improved daytime dysfunction (-0.33 [-0.65, -.0.01]), but led to a small decline in sleep efficiency (0.06 [0.01, 0.10]). MCMT improved sleep disturbance ( 0.31 [-0.55, -0.07]). CONCLUSION: Both GSC and MCMT improved sleep quality, although neither intervention appeared superior. Sleep disturbance was improved in the MCMT group and daytime dysfunction was improved in the GSC group. Future studies would benefit from including a true control, objective sleep measures, and investigation of potential mediators.