Table 1. The changes in the passive dorsiflexion range of motion (DF ROM), passive stiffness, passive torque at DF ROM, first stretch sensation, pain pressure threshold (PPT), shear elastic modulus of medial gastrocnemius muscle, and H/M ratio before (PRE) and after (POST) the 3-minute roller massage intervention in both male and female participants. Effect sizes (Cohen’s d for t tests and partial η2 (ηp2) for a split-plot 2x2 analysis of variance (ANOVA)) are listed in the second column for each parameter. Male (N = 15) Female (N = 14) ANOVA results PRE POST PRE POST Interaction effect Main effect for time DF ROM (°) 27.0 ± 11.7 30.9 ± 10.1* 32.4 ± 5.5 37.4 ± 4.6** F = 0.17, p = 0.69 F = 29.5, p < 0.01 d = 0.36 d = 0.94 ηp2 < 0.01 ηp2 = 0.513 Passive stiffness (Nm/°) 0.71 ± 0.21 0.70 ± 0.20 0.51 ± 0.15# 0.53 ± 0.14 N/A N/A d = 0.06 d = 0.13 N/A N/A Passive torque at DF ROM (Nm) 24.4 ± 12.3 28.5 ± 13.2* 18.0 ± 7.8 23.0 ± 8.4** F < 0.01, p = 0.99 F=8.0, p < 0.01 d = 0.32 d = 0.62 ηp2 < 0.01 ηp2 = 0.222 First Stretch Sensation (°) 12.8 ± 10.5 17.7 ± 10.6* 19.6 ± 7.1 25.7 ± 5.7** F = 0.31, p = 0.86 F = 23.6, p < 0.01 d = 0.47 d = 0.95 ηp2 < 0.01 ηp2 = 0.457 PPT (kg) 3.0 ± 1.1 3.6 ± 1.3** 2.5 ± 0.9 3.0 ± 1.1** F = 0.12, p = 0.73 F = 23.3, p < 0.01 d = 0.55 d = 0.54 ηp2 < 0.01 ηp2 = 0.455 Shear elastic modulus (kPa) 8.9 ± 1.1 9.5 ± 1.5 9.3 ± 1.8 9.9 ± 1.5 F = 0.06, p = 0.81 F = 3.6, p = 0.07 d = 0.46 d = 0.39 ηp2 < 0.01 ηp2 = 0.113 H/M ratio 0.80 ± 0.29 0.76 ± 0.33 0.63 ± 0.30 0.57 ± 0.27 F = 1.07, p = 0.31 F = 1.70, p = 0.20 d = 0.13 d = 0.20 ηp2 = 0.037 ηp2 = 0.202 #: p < 0.05: significant difference between male and female at PRE value **: P < 0.01: significant difference from the PRE value. *: p < 0.05,