Aims: To investigate exercise dose-response relationships and estimate optimal exercise dose associated with clinically meaningful improvements in pain intensity and disability in adults with chronic low back pain disorders (CLBDs).
Methods: A systematic review with non-linear dose-response network meta-analysis was conducted. We searched six databases, two trial registries, and performed citation searches from inception to 3 June 2025. Randomised controlled trials evaluating exercise interventions in adults (≥18 years) with CLBDs were included. Outcomes were disability and back pain intensity measured at short-term (>1 day to ≤3 months), intermediate-term (>3 months to <12 months), and long-term (≥12 months) follow-up. Risk of bias was assessed using Cochrane RoB2 and certainty of evidence using the minimally contextualised GRADE framework. A 5-point change on a 0-100 scale was considered clinically meaningful.
Results: A total of 239 trials (252 reports) were included. Most studies (99.2%) included participants with chronic non-specific low back pain and only two trials included radicular presentations. Our analysis indicated that the greatest short-term improvements in disability were achieved with a frequency of four sessions per week, with a per-session duration of 25 minutes, delivered over 13 weeks. For pain intensity, the model-predicted optimal dose was three sessions per week, 30 minutes per session, over eight weeks. Credible intervals overlapped across most dose levels, indicating considerable uncertainty regarding a single optimal dose. Majority of studies (84%) were at high risk of bias with a very low to low GRADE certainty. 28.5% of trials reported adverse events and were predominantly non-serious musculoskeletal complaints.
Conclusions: Exercise training provides clinically meaningful short-term benefits for chronic non-specific low back pain across a range of low-to-moderate doses. Current evidence does not support a single optimal exercise dose suggesting flexibility in tailoring prescription for patient preferences and clinical context. Evidence for radicular low back pain remains limited.