Pre-fatigue enhancing both long-term stability and sensitivity of direct-ink-writing printed sensors

•A specially-designed strain-isolation layer enable long-term fatigue testing for the direct-ink-writing (DIW)-printed strain sensors in high strain level.•A fatigue-dominated initiation-propagation-arrest mechanism of multi-parallel cracks is to achieve the long-term stability for DIW-printed strain sensors.•The fatigue-based modulation strategy is proposed to improve sensor sensitivity in the framework of DIW technology and conductive paste.