Effects of exercise dose based on the ACSM recommendations on pain and disability in non-specific low back pain patients: a systematic review and meta-analysis of randomized controlled trials

Background Low back pain (LBP) is characterized by pain or discomfort between the costal margins and the inferior gluteal folds, with or without radiation to the lower limbs. It significantly affects patients’ overall health and quality of life. Purpose This study aims to investigate the effects of exercise therapy and adherence to the American College of Sports Medicine (ACSM) guidelines on treatment outcomes in patients with LBP. Methods The literature search, concluded on 26 June 2025, included studies that investigated the effects of exercise interventions in patients diagnosed with LBP and that provided sufficient data for calculating the Standardized Mean Difference (SMD). The primary outcome measure was the Visual Analogue Scale (VAS), and secondary outcomes included the Oswestry Disability Index (ODI) and the Roland-Morris Disability Questionnaire (RDQ/RMDQ). Results Among 22,723 records, 36 studies (n = 2,284) were eligible for qualitative synthesis. The meta-analysis showed an overall SMD for pain of −1.28 (95% CI -1.63, −0.94). In the subgroup with high adherence to the ACSM guidelines, the pooled SMD was −1.98 (95% CI -2.58, −1.38), whereas in the low- or uncertain-adherence subgroup it was −0.72 (95% CI -1.01, −0.43). For disability, the overall SMD was −1.10 (95% CI -1.58, −0.62) on the ODI. High adherence yielded a mean difference of −1.31 (95% CI -1.81, −0.80) and low adherence yielded −0.99 (95% CI -1.71, −0.28). The overall SMD was −0.77 (95% CI -1.07, −0.47) on the RDQ; the corresponding values were −1.39 (95% CI -2.51, −0.26) for high adherence and −0.54 (95% CI -0.76, −0.31) for low adherence. Conclusion The results suggest that exercise interventions with high adherence to the ACSM recommendations are more effective in improving pain and disability in individuals with LBP than interventions with low or uncertain adherence to these guidelines.