The application of smart wearable devices in the field of sports is becoming more and more widespread, and this paper deeply researches the assessment effect of smart wearable devices on the sports performance of basketball players. Through the time-frequency analysis method, the athlete’s EMG signal is monitored, and the time-domain and frequency-domain features of the athlete’s myoacoustic signal are extracted. At the same time, the monitoring method was compared with the traditional electrode method to test the performance of the myoelectric signal monitoring of the monitoring method in this paper. By comparing the FMS test results of athletes before, during, and after the adoption of smart wearable devices, the effectiveness of smart wearable devices in improving basketball players’ sports performance is explored. The performance of this paper’s EMG signal monitoring method is better than the traditional electrode method in terms of EMG signal RMS value, signal-to-noise ratio (SNR) and mean power frequency (MPF), and the p-value is less than 0.05, which makes this paper’s method a better evaluation performance.