A miniaturized wireless electrical impedance myography platform for the long-term adaptive muscle fatigue monitoring

• A miniaturized wireless EIM platform with flexible microneedle array electrodes (MAE) enables long-term, adaptive muscle fatigue monitoring. • MAEs outperform conventional electrodes in skin-electrode contact impedance, as validated by simulations and tests. • The integrated smartphone app allows wireless operation, real-time data transmission, and processing of muscle impedance. • A seven-day adaptive fatigue training study confirmed the platform's ability to detect muscle adaptations and serve as a reliable fatigue indicator.