Muscle & Tendon

Document Type



This study aims to explore the effects of running habits on the morphology of gMTU (medial gastrocnemius-Achilles tendon unit) and plantar flexion torque, to reveal the adaptive changes of different running habits. Male habitual distance runners with forefoot strike pattern (FFS, n=10), male habitual distance runners with rearfoot strike pattern (RFS, n=10), and male non-runners (NR, n=10) were recruited. The Mindray M7 Super ultrasonography system was used to measure the morphological characteristics of the gMTU. A dynamometer was utilized to determine the plantar flexion torque. One-way ANOVA and Nonparametric Test were used for analysis. The significance level was set as 0.05. Significant differences between groups were detected on muscle fascicle length (FL) (p < 0.05), Normalized FL (p < 0.05), and pennation angle (PA) (p < 0.01), while no significant difference was observed in other parameters. Specifically, the FL and Normalized FL were greater in FFS than NR (p < 0.05), while the PA was smaller in FFS than NR (p < 0.05). These results suggest that long-term running with FFS pattern could induce a greater contraction velocity and a more efficient force transmitting of the medial gastrocnemius (MG).