Sex Differences in the Mechanical and Neurophysiological Response to Roller Massage of the Plantar Flexors

Abstract

Self-massage using foam rollers, sticks, or balls has become a popular technique to enhance joint range of motion (ROM). Although increases are reported to be larger in females than males, the mechanisms of this observation are unclear. The present study aimed to investigate the effect of roller massage (RM) on ROM, passive tissue stiffness, and neurophysiological markers as a function of sex. Males (n = 15, 22.8 ± 2.9 yrs.) and females (n = 14, 21.1 ± 0.7 yrs.) performed three 60-second bouts of calf RM. Outcomes assessed pre-, and post-intervention included passive dorsiflexion (DF) ROM, passive tissue stiffness, passive torque, DF angle at the first stretch sensation, shear elastic modulus, and spinal excitability. DF ROM (+35.9 %), passive torque at DF ROM (+46.4 %), DF angle at first stretch sensation (+32.9 %), and pain pressure threshold (+25.2 %) increased in both groups (p<.05) with no differences between males and females (p > 0.05). No changes were observed for passive stiffness, shear elastic modulus, and spinal excitability (p > 0.05). Roller massage may increase ROM independently of sex, which, in the present study, could not be ascribed to alterations in passive stiffness or neurophysiological markers. Future studies may further elucidate the role of sensory alterations as possible factors driving RM-induced changes in flexibility.