Contribution of Plantar Fascia and Intrinsic Foot Muscles in a Single-Leg Drop Landing and Repetitive Rebound Jumps: An Ultrasound-Based Study

The plantar fascia and intrinsic foot muscles (IFM) modulate stiffness. However, it is unclear whether the corresponding ultrasonography findings reflect it. This study aimed to examine effect of IFM morphologies on force attenuation during landing reactivity when jumping in healthy adults (n = 21; age, 21–27 years). Thickness, cross-sectional area (CSA), hardness fascia, abductor hallucis (AbH), flexor brevis (FHB) were measured using ultrasonography. Single-leg drop repetitive rebound tests assessed ground reaction (GRF) reactive jump index (RJI), respectively. CSA FHB was negatively correlated with maximum vertical GRF (r ?0.472, p 0.031) single-leg test. AbH contact time ?0.478, 0.028), thickness positively height 0.615, 0.003) RJI 0.645, 0.002) bound In multivariate regression analysis, only associated (? 0.152, 95% confidence interval: 7.219–38.743, 0.007). may contribute landing. facilitate high minimal time.