Optimal exercise dose in adults with chronic low back pain disorders: systematic review with dose-response network meta-analysis

Abstract

Objective To quantify exercise dose-response relationships and estimate the optimal dose in adults with chronic low back pain disorders (CLBDs). Design Systematic review with random-effects model-based (non-linear) dose-response network meta-analysis. Risk of bias was assessed with Cochrane RoB 2 and certainty with the minimally contextualised Grading of Recommendations, Assessment, Development and Evaluation framework. A ≥5-point change (scaled 0–100) was predefined as clinically meaningful. Data sources Six databases, two trial registries and citations were searched to 3 June 2025 Eligibility criteria Randomised controlled trials of exercise in adults (≥18 years) with CLBDs assessing disability or back pain at short (>1 day and ≤3 months), intermediate (>3 months and<12 months) and long-term (≥12 months) follow-up. Results We included 239 trials (252 reports); 99.2% included non-specific chronic low back pain; two trials included radicular presentations. The model-predicted optimal dose for short-term disability was 4 sessions/week, 25 min/session over 13 weeks. For short-term pain intensity, the optimal dose was 3 sessions/week, 30 min/session over 8 weeks. However, credible intervals of most dose-levels overlapped. Few dose combinations were clinically meaningful beyond the short term. 84% of trials were at high risk of bias and certainty was very low to low. Adverse events (reported in 28.5% of trials) were predominantly non-serious and musculoskeletal. Conclusions Exercise training delivered at low to moderate doses was associated with short-term improvements in disability and pain intensity, which may be clinically meaningful, with limited additional benefit at higher exposure. Model-predicted doses provide guidance for exercise prescription; but the available evidence does not support a single optimal exercise dose and should be interpreted with caution given the low to very low certainty of evidence. Exercise training for radicular presentations is a key evidence gap.