Influence of carbon-plated running shoes and fatigue on lower limb biomechanics.

This study aimed to investigate the effects of shoe longitudinal bending stiffness and fatigue state on lower limb joint biomechanics and impact loading characteristics during running. Sixteen participants were tested using a 3D motion capture system and force platforms to collect and analyze kinematic and kinetic data of the metatarsophalangeal, ankle, knee, and hip joints, as well as the average vertical loading rate (VALR) of ground reaction force, under two footwear conditions before and after induced running fatigue. Carbon-plated shoes significantly restricted metatarsophalangeal joint flexion, while hip transverse plane range of motion was notably affected by fatigue. Fatigue primarily reduced knee joint flexion-extension moment and stiffness, increased ankle pronation moment, and elevated VALR. A significant interaction effect between fatigue and shoe type was observed on VALR, with non-carbon shoes demonstrating superior shock attenuation under fatigue. Shoe structure and fatigue state significantly influence multi-joint coordination and control in the lower limbs. This study supports the "distal restriction-proximal compensation" mechanism, suggesting that while carbon-plated shoes enhance propulsion efficiency, the restricted distal mobility, especially under fatigue, increases compensatory loading and injury risk in proximal joints.