Thermo-Adaptive Biointerfacial Electrodes Enable Dynamic and Reusable ECG Monitoring

Unstable skin-electrode interfaces hinder dynamic electrocardiogram (ECG) monitoring during exercise. Herein, a thermo-adaptive biointerfacial (TAB) electrode is developed using a physiological temperature-driven molecular-microstructural synergy (PTD-MMS) strategy, integrating a phase-change polymer, biomimetic trapezoidal microchannels, and a conductive Ag-fabric network to address this bottleneck. At body temperature, this design achieves strong, reversible adhesion (39.6 N m^-1, 12.4 switching ratio) while retaining over 90% of initial strength after 25 reattachment cycles, enabling robust fixation yet gentle detachment. Biomimetic microchannels enable active sweat management with a 58.6 g m^-2 h^-1 water vapor transmission rate and 7.5 μL s^-1 liquid removal to preserve stable skin contact. Outperforming conventional gel electrodes under movement, the TAB electrode delivers high-fidelity ECG signals (67.9 dB SNR) and maintained reliable monitoring during standing, walking, and football training. Notably, heart rate variability correlated with body mass index in the cohort, supporting potential for personalized health supervision, while this PTD-MMS approach establishes a targeted platform for adaptive bioelectronic interfaces in dynamic exercise monitoring.