Abstract
The biomechanical characteristics of the erector spinae muscles are crucial for evaluating treatment effectiveness. Although it is widely believed that myofascial release directly impacts muscle biomechanics, there has been limited research directly comparing manual (MMR) and tool-assisted (TMR) applications. This study aimed to fill this gap by investigating the immediate biomechanical effects of MMR and TMR on the erector spinae muscles, using the MyotonPRO device to measure and compare changes in muscle tone, stiffness, and elasticity. Thirty healthy adult physical therapy students (21.19 ± 1.93 years) were recruited and randomly assigned to either the MMR or TMR group. Biomechanical properties (elasticity, tone, and stiffness) were measured before and immediately after three sets of 15 repetitions of the assigned intervention. Post-intervention, the MMR group showed a significant decrease in muscle stiffness and tone (p < 0.0125), while the TMR group showed no significant changes in any of the measured parameters (all p > 0.05). A comparison of the percentage change from baseline also revealed significant differences in elasticity, stiffness, and tone between the two groups (p < 0.0125). This study demonstrates that MMR produces a significant and immediate reduction in erector spinae muscle stiffness and tone, an effect not observed with TMR.