ABSTRACT
Chronic low back disorders are the leading cause of direct and indirect healthcare burden globally. Exercise training improves pain intensity, mental health and physical function. However, the optimal prescription variables are unknown. We aim to compare the efficacy of various exercise dosages for chronic low back disorders to identify the optimal prescription variables. Six databases (Medline, SPORTDiscus, CINAHL, PsycINFO, EMBASE and CENTRAL), trial registries (ClinicalTrials.gov and WHO International Clinical Trials Registry Platform) and reference lists of prior systematic reviews will be searched, and we will conduct forward and backward citation tracking. We will include peer-reviewed randomised controlled trials (individual, cluster or cross-over trials) published in English or German language comparing exercise training to other exercise training or non-exercise training interventions (conservative, non-surgical, non-pharmacological, non-invasive treatments, placebo, sham, usual/standard care, no-treatment control, waitlist control) in adults with chronic low back disorders. Outcomes will include pain intensity, disability, mental health, adverse events, adherence rate, dropout rate and work capacity. Version 2 of the Cochrane risk-of-bias tool will be employed. The dose will be categorised as cumulative dose (total and weekly minutes of exercise training) and individual dose prescription variables (intervention duration, session duration, frequency and intensity). Dose-response model-based network meta-analysis will be used to assess the comparative efficacy of different exercise doses to determine a dose-response relationship. The certainty of evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation. Information about optimal exercise training dosage will help in enhancing treatment outcomes.
ABSTRACT
Objectives: The relationship between exercise training variables and clinical outcomes in low back pain (LBP) is unclear. The current study aimed to explore the relationship between exercise training parameters and pain intensity in individuals with chronic LBP. Methods: This study is a secondary analysis of a previously reported randomised controlled trial comparing the effects of general strength and conditioning to motor control exercises and manual therapy. This secondary analysis includes adults with chronic LBP (n=20) randomised to the general strength and conditioning programme only. Primary outcomes of this analysis were exercise training parameters (time under tension, rating of perceived exertion (RPE), session duration, session-RPE and training frequency) and pain intensity (0-100 mm visual analogue acale) measured every 2 weeks from baseline to 6 months follow-up. Linear mixed models with random effects (participants) and allowance for heterogeneity of variance (study date) were used to determine the association between pain intensity and training parameters over time. Results: Mean (95% CI) pain intensity decreased over time from baseline to 6 months follow-up by 10.7 (2.8 to 18.7) points (p=0.008). Over the 6-month intervention, lower pain intensity was associated with higher RPE (ß (95% CI) -27.168 (-44.265 to -10.071), p=0.002), greater time under tension (-0.029 (-0.056 to -0.001), p=0.040) and shorter session duration (1.938 (0.011 to 3.865), p=0.049). Conclusion: During 6 months of general strength and conditioning, lower pain intensity was associated with higher participant-reported training intensity, greater volume and shorter session duration. To ensure positive outcomes to exercise training, these variables should be monitored on a short-term basis. Trial registration number: ACTRN12615001270505.