A Sweat Absorbing Skin Electrode for Electrophysiology During Exercise

Abstract Electrophysiological signals are commonly used to assess health performance, providing valuable information on body status. However, stable signal acquisition by commercial Ag/AgCl gel or metal electrodes is susceptible to electrode/skin interface interferences due to perspiration and motion during exercise. To address this challenge, herein a sweat absorbing skin electrode (SAE) is designed, which can not only become softer and more adhesive but also enhance conductivity after sweat during exercise. The resulting stable interface between SAE/skin after sweat enables accurate and continuous electrophysiological measurement during exercise. SAE is demonstrated by assembly of MXene (Ti₃C₂T_X) aerogel and zwitterionic polymer, where Ti₃C₂T_X aerogel works as conductive skeleton and zwitterionic polymer endows skin conformability as well as expediting interfacial charge transfer by the inherent ions. SAE can monitor a variety of electrophysiological signals during exercise. As an example, electromyogram (EMG) signals are acquired to assess muscle fatigue, which is impossible by commercial gel electrodes. Via machine learning, the correlation between EMG and physiological markers (body fat percentage (BF) and body mass index (BMI)) are constructed. The research shows that sweat‐absorbing SAEs can reliably monitor electrophysiological signals during exercise, such as muscle status, leading to evidence‐based scientific guidelines for sports and rehabilitation training.