Deep soft-tissue massage applied to healthy calf muscle has no effect on passive mechanical properties : a randomized, single-blinded, cross-over study

![CDATA[Background: Massage is often applied as a method for relaxation or for therapeutic effect with the intention of improving flexibility or reducing stiffness in the musculotendinous tissue. However, there is no substantive evidence which demonstrates that massage has an effect on the mechanical characteristics of musculotendinous tissue. Purpose: This study investigated the effect of massage on the passive mechanical properties of the calf muscle complex with comparison to heat therapy. Methods: This was a randomised, single-blinded cross-over study. Twenty-nine healthy volunteers (mean (SD) 22 (6) years of age, 174 (8) cm in height and 71 (13) kg body mass) who provided written and informed consent (University of Western Sydney Human Research Ethics Committee granted ethical approval – H10544) were tested for passive mechanical characteristics before (pre-), immediately following (post-) and 30 minutes after (post30-) either massage or superficial heating to the calf muscle complex on one side and the contralateral leg which was not treated. Using an instrumented footplate, passive calf stiffness was determined by rhythmically oscillating the ankle into dorsiflexion and calculating the quotient of the torque-displacement curve between an applied torque of 0.1–0.2 Nm kg−1. Calf muscle flexibility (angular displacement at an applied torque of 0.2 Nm kg−1) was also determined. All tests were performed with the knee extended and flexed (30°). Muscle activity of the triceps surae and tibialis anterior was monitored using surface electromyography to ensure that all tests were passive. A 4 × 3 repeated measures ANOVA was used to compare outcomes with respect to intervention and interval with Bonferroni correction made to reduce the risk of a type 1 error. Results: There were no statistical or functionally significant differences detected between conditions (massage, heat, control) at any interval (pre-, post, post30-) or at any applied torque value in either the knee extended (p = 0.95) or flexed (p = 0.80) positions for the dynamic stiffness or calf flexibility (p > 0.35). Conclusion(s): This study empirically determined that massage did not cause a change in the passive mechanical properties of the calf muscle complex of normal healthy individuals. The findings of this study are based on methods that were shown to be very reliable both within and between sessions of testing. Implications: Massage may have purported psychological, physiological and physical benefits. However, this study demonstrated that it does not affect the musculotendinous passive mechanical properties.]]