A Knittable, Muscle-Fiber-Inspired Fiber with Ultra-Stretchability, Waterproof Property and High Conductivity for Wireless Power and Wide-Range Sensing

• • The fiber achieves an electrical conductivity of 3.76 × 10^5 S m−1 while sustaining stretchability exceeding 3500%, directly addressing the conductivity-stretchability trade-off that limits conventional conductive fibers. • • The twisted-pair capacitive strain sensor exhibits a linear response up to 1000% strain, enabling precise monitoring of both large joint movements and subtle physiological signals such as wrist pulse and respiration. • • The WPU/fluoropolymer sheath provides waterproofness and mechanical abrasion resistance, ensuring stable performance under repeated deformation and wet conditions, critical for all-weather wearable applications. • • The fiber can be woven into textiles and function as a receiving coil for wireless power transfer, demonstrating practical integration into smart textiles without compromising mechanical compliance.