Purpose: The purpose of this study is to investigate the therapeutic effects of lumbar strengthening exercises performed on different surfaces (stable versus unstable) in reducing pain intensity, improving muscular endurance, and enhancing postural balance in individuals with low back pain.
Method: Twenty participants with visual analog scale (VAS) scores ranging from 4 to 7 were recruited and randomly assigned to either an unstable surface lumbar exercise group (USLEG, n=10) or a stable surface lumbar exercise group (SSLEG, n=10). Both groups completed a 50-minute lumbar strengthening program three times per week for eight weeks.
Results: A two-way repeated-measures ANOVA revealed significant group-by-time interaction effects for both the VAS and the Oswestry Disability Index (ODI) (both p<.001), with the USLEG showing greater reductions in pain and functional disability. Regarding muscular endurance, significant interaction effects were observed in the Trunk Flexion Endurance Test (TFET), Trunk Extension Endurance Test (TEET), and Trunk Lateral Endurance Test (TLET) (all p<.001), with the USLEG showing more pronounced improvements. Furthermore, postural balance metrics, including posteromedial (PM, p<.001), posterolateral (PL, p < .05), and Composite Score (CS, p<.05), exhibited significant interaction effects, with the USLEG demonstrating enhanced stability compared to the SSLEG.
Conclusion: These findings suggest that incorporating unstable surfaces into lumbar strengthening protocols is more effective than traditional stable surface exercises for alleviating pain and enhancing trunk stability. This study highlights the clinical utility of unstable surface training as a strategic intervention to improve functional capacity and neuromuscular control in patients with chronic lower back pain.