This study aims to propose and validate an innovative method for detecting and classifying muscle fatigue, based on surface electromyography (sEMG) signals, with a focus on accurately identifying and classifying static muscle fatigue. By recruiting seven healthy young volunteers (comprising two males and five females), this research conducted a series of fatigue tests, during which the participants' surface electromyographic signals and their subjective fatigue scores were meticulously recorded. The study extracted 18 features from the surface electromyographic signals, including time domain, frequency domain, and time-frequency domain characteristics. These features were then labeled as "normal" or "fatigued" based on the participants' Borg CR-10 subjective fatigue scale. In the data processing phase, 80% of the statistical features were selected as the training dataset for machine learning models (CNN-SVM, KNN, SVM, RF), with the remaining 20% serving as the test dataset to evaluate the performance of the four algorithms in terms of accuracy in muscle fatigue classification. The experimental results indicate that in the evaluation mode utilizing all features, the CNN-SVM model achieved the highest accuracy and F1-score, at 86.13% and 84.58% respectively. In the mode that only utilized the four principal sEMG signal features, the KNN model exhibited the best performance with an accuracy rate of 75.87%.The muscle fatigue recognition model proposed in this study is of paramount significance for monitoring muscle fatigue in static sitting and standing postures.