Systematic Review
What is the association between exercise adherence and the effects of exercise on pain intensity and functional limitations in adults with chronic non-specific low back pain (CNSLBP)?/r/nSystematic review with meta-analysis./r/nAdults with CNSLBP./r/nRandomised controlled trials of exercise compared with no exercise (eg, usual care, placebo/sham or another conservative treatment). Adherence to exercise must have been reported./r/nPain intensity and functional limitations./r/nThis study included 46 trials with 56 exercise groups. High exercise adherence (80 to 100%) was associated with reduced pain intensity (0 to 100 scale) (MD -14.32, 95% CI -18.61 to -10.03, low certainty) and functional limitations (0 to 100 scale) (MD -8.08, 95% CI -10.68 to -5.49, low certainty). Moderate exercise adherence (60 to 79%) was not associated with reduced pain intensity (MD -4.53, 95% CI -9.39 to 0.34, very low certainty) or functional limitations (MD -2.75, 95% CI -6.00 to 0.51, very low certainty). Low exercise adherence (< 59%) was associated with reduced pain intensity (MD -5.33, 95% CI -10.00 to -0.66, low certainty) and functional limitations (MD -4.43, 95% CI -7.14 to -1.72, moderate certainty). Compared with low adherence, additional differences in outcomes for moderate and high adherence were mostly negligible./r/nHigher exercise adherence is associated with larger improvements in clinical outcomes in adults with CNSLBP, although overall differences are small compared with lower adherence. Other factors besides adherence between the trials and exercise programs could explain these results. Further research is needed to determine the causal effect of exercise adherence on outcomes in adults with CNSLBP./r/nPROSPERO CRD42023447355 and Open Science Framework https://osf.io/7p6dw/.