Highly Stretchable, Resistance‐Stable, Conductive Liquid Metal Core‐Sheath Fibers Enable Ultrastable and Supersensitive Physiological Monitoring

) demonstrated by the composite SBS/LM fiber (SLMF). Notably, SLMF retained remarkable resistance stability (variation rate of only 105.31% under 800% tensile deformation) even under repeated strain, washing, and exposure to various extreme environments such as acids, bases, and high temperatures. Moreover, due to the unique grooved structure on the fiber surface, SLMF generates a high voltage output, maintaining ultrastable electrical output after prolonged exposure to high-frequency mechanical impacts. Furthermore, the integration of SLMF into stretchable triboelectric sensors paves the way for hypersensitive joint movement sensing and respiratory status monitoring. Consequently, this discovery offers invaluable insights and guidance for the fabrication and advancement of conductive fibers for skin-interfaced wearable electronics.