Immediate effects of myofascial release and Kinesio taping on muscle viscoelasticity and functional performance in low back pain: a three-arm controlled study

Background Chronic low back pain (LBP) represents a major cause of functional limitations and disability worldwide.Objective To compare the immediate effects of myofascial release technique (MRT), kinesio taping (KT), and no intervention on muscle viscoelastic properties, pain, lumbar mobility, and functional performance.Methods Sixty-six participants with chronic nonspecific LBP were randomly assigned to MRT, KT, or control groups. Both interventions were delivered in a single session, while the control group rested for an equivalent period. Primary outcomes were paraspinal muscle tone, stiffness, elasticity (MyotonPRO). Secondary outcomes included pain (The Visual Analog Scale-VAS), lumbar mobility (Modified Schober Test), lifting capacity (Progressive Isoinertial Lifting Evaluation-PILE), functional performance (The 1-Minute Stair Climb Test-1-min SCT). All outcomes were assessed immediately before and after the intervention session. Potential clinical relevance was examined using the smallest worthwhile change (SWC).Results MRT produced a greater reduction in overall bilateral muscle tone than KT and control (group×time interaction: p = .004, ηp2 = 0.161), with the MRT change exceeding the SWC. Overall bilateral muscle stiffness decreased significantly within the MRT group (p = .011, Kendall’s W = 0.298), exceeded the SWC, and was greater than that in the control group (p = .021). Pain reduction was greater in both the MRT and KT groups than in the control group (group×time interaction:p < .001, ηp2 = 0.260), with both interventions exceeding their SWC thresholds. Within-group PILE performance improved in MRT (p = .021, Kendall’s W = 0.242) and KT (p = .033, Kendall’s W = 0.208), with both exceeding their SWC thresholds. 1-min SCT improved over time (p < .001, ηp2 = 0.189), although no significant group×time interaction was observed (p = .854); only the MRT change exceeded the SWC.Conclusion A single MRT session was associated with immediate improvements in muscle tone, stiffness, pain, lumbar mobility, and lifting performance, whereas KT was associated with immediate reductions in pain and improvements in lifting performance. These findings are limited to the immediate post-treatment period and should not be interpreted as evidence of sustained clinical effectiveness.